Abstracts of EuroPerio8, London, UK, 3-6 June.

doi: 10.1111/jcpe.12397

Research Session and Clinical Innovation Research session: Aetiology & pathogenesis 1 RCI01 Horizontal and vertical transfer of a Porphyromonas gingivalis-induced dysbiotic microbiota leads to periodontal bone loss in a mouse model M. Payne, A. Hashim, A. Alsam, J. Aduse-Opoku, M. Curtis London/United Kingdom Aim: Periodontal disease is associated with a markedly different microbiology compared to health. However, the precise role this dysbiotic microbiome plays in disease is not fully understood. We used the mouse model of periodontal disease to analyse the role of oral dysbiosis on periodontal bone destruction. Specifically to characterise the dysbiotic oral microbiota of Porphyromonas gingivalis challenged mice and transfer of this community horizontally into healthy germ free (GF) animals and vertically into the off spring of challenged mice. Material and Methods: The symbiotic and dysbiotic oral microbiota of Specific Pathogen Free (SPF) mice were characterised by culture and non-culture dependant techniques. In co-caging experiments GF mice were housed with SPF mice and the horizontal transmission of these oral microbiomes monitored and alveolar bone loss assessed. The vertical transmission of these microbiomes was also assessed and alveolar bone loss measured. Results: The dysbiotic oral microbiota was significantly different to unchallenged mice (qualitative and quantitative composition) and completely transferred into GF mice within 14 days. This led to significantly increased periodontal bone loss when compared to unchallenged controls. The P. gingivalis-induced dysbiotic microbiota appeared stable for 28 weeks post-challenge and was transferred into offspring producing significantly increased bone loss compared to the offspring of unchallenged mice.

labeled, isolated from fresh human blood and pre-stimulated with the OMV. During pre-stimulation following inhibitors were used: anti IL-10, Rapamycin, AKT-Inhibitor. Re-stimulation of the washed monocytes was performed after 24 h with whole live Pg or bacterial lipopolysaccharide (LPS). Supernatants of two time points (24 and 48 h) were analyzed by TNFa, IL-1b, IL-10 ELISA. Statistical analysis: unpaired two-tailed Student’s t-test. Results: Our data revealed that monocytes pre-stimulated with OMV are rendered refractory to stimulation with live bacteria and LPS, respectively, e.g. fail to mount a TNFa response compared to the non-pre-stimulated control (p < 0.0001). Further experiments show that neutralization of IL-10 during pre-stimulation partially restored TNFa levels after re-stimulation with Pg. Endotoxin tolerance-capacity was further shown to be sensitive to Rapamycin (p = 0.0008 when compared to no-Rapamycin during pre-stimulation) and AKT inhibition and, thus, depends on PKB/Akt/mTOR-signaling. Conclusion: Taken together, our results describe OMV as bacterial sentinels that promote monocyte tolerance to Pg and other bacteria. Drugs targeting PKB/Akt signaling pathways might be beneficial in restoring the host immune response to periodontal pathogens and represent a therapeutic option in the therapy of periodontal disease.

RCI03 Upregulation of bid/tbid during osteoblast apoptosis induced by gingipains F. Zhang, M. Liang Guangzhou/China Aim: To investigate Bcl2 pro-apoptotic sub-family member Bid/tBid protein expression and regulation during osteoblast apoptosis induced by gingipains.

Conclusion: Symbiotic and dysbiotic microbiota can completely transfer horizontally into GF mice and vertically into offspring. In both instances transmission of the dysbiotic microbiota is sufficient to cause increased alveolar bone loss compared to controls suggesting a critical role for the microbiota in the disease process.

Material and Methods: Gingipains were extracted from culture supernatants of P.g W83. Activities of gingipains were measured by substrate degradation. Osteoblast MC3T3-E1 cells were cultured in the presence/absence of gingipains. Apoptosis of osteoblasts was determined by flow cytometry. Protein expression was detected by Western Blotting and gene expression was examined by real-time PCR.

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Results: Osteoblast apoptosis increased significantly 16 h after treated with 8.348 U/l gingipains and reached a peak between 16 and 48 h. The protein expression of Bid decreased within 8 h after treated with gingipains followed by upregulation after long term (24–48 h) treatment. The active form of Bid (tBid) gradually increased from 8 h and maintained at high level up to 72 h in the presence of gingipains. Real-time PCR data showed that Bid mRNA level was 1.5-fold higher compared to control when osteoblasts incubated with gingipains for 16 h. The upregulation of Bid mRNA expression was blocked by either 0.1 mmol/l TLCK (a cysteine protease inhibitor) or PFT-a (p53 blocker). The pro-survival protein ERK and PKB activities decreased from 2 h after gingipains treatment and remained at low level up to 24 h. Inhibition of ERK activity by PD-325901 or PKB avtivity by MK-2206 upregulated Bid mRNA level by 1.5-fold. Combination of the two blockers further increased Bid mRNA expression.

Molecular mechanisms underlying P. gingivalis outer membrane vesicle-mediated tolerance T. Waller, S. Jepsen, J. Deschner, I. Bekeredjian-Ding Bonn/Germany Aim: It has been suggested that Porphyromonas gingivalis (Pg) contributes to periodontal disease by altering the host immune response. Here, we hypothesized that outer membrane vesicles (OMV) secreted by Pg play a key role in the immunomodulation exerted by Pg. Material and Methods: OMV were prepared from sterile Pg liquid culture supernatants by ultracentrifugation and analyzed by trans-electron-microscopy. Next, CD14+ monocytes were

© 2015 European Federation of Periodontology

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Conclusion: Gingipains induce osteoblast apoptosis, which involoves in the upregulation and activation of Bcl2 pro-apoptotic protein Bid. Regulation of Bid gene expression is via p53 and ERK/PKB signaling pathways by gingipains.

RCI04 Bortezomib inhibits osteoclastogenesis and P. gingivalis lipopolysaccharide-induced alveolar bone erosion in mica Y. Lee, Y. Kim, H.J. Kim, J. Kim Daegu/Korea Aim: Persistent bacterial stimulation of periodontium causes periodontitis, characterized by the inflammation and destruction of both soft and hard tissues. Cytokines produced by inflammatory cells including RANKL, TNF-a, and IL-1 accelerates the differentiation and activation of osteoclasts, the bone-resorbing cells of macrophage/monocyte origin. Untreated periodontitis not only results in tooth loss due to excessive alveolar bone loss, but also has been related to other systemic diseases such as diabetes and cardiovascular diseases. In the present study, we utilized a mouse periodontitis model and examined the antiresorptive role of bortezomib, a proteasome inhibitor that was extensively studied in multiple myeloma bone diseases. Material and Methods: To evaluate the effect of bortezomib on osteoclast differentiation, mouse bone marrow macrophages were stimulated with RANKL and M-CSF for 3 days. To test the activities of MAP kinases, cells were incubated for 24 h in the presence of bortezomib and serum-starved for 6 h, before re-stimulation with either M-CSF or RANKL. Alveolar bone resorption was induced by injecting 20 lg of P. gingivalis LPS in the gingiva of molar in the lower jaw of mice. Tissue sections were analyzed by TRAP staining and histomorphometry. Results: Bortezomib significantly inhibited osteoclast differentiation in vitro. Bortezomib also reduced the expression of osteoclast marker genes, nuclear localization of NFATc1, and ERK activation. Bortezomib significantly decreased osteoclastogenesis and alveolar bone erosion in mice challenged with P. gingivalis LPS. Conclusion: Bortezomib inhibited osteoclast differentiation and alveolar bone erosion in mice, suggesting a therapeutic potential for periodontitis.

RCI05 Regulation of the immunoregulatory receptor B7-H1 on oral epithelial cells by Porphyromonas gingivalis F. Jarzina, S. Groeger, J. Meyle Giessen/Germany Aim: Overexpression of the immunoregulatory receptor B7-H1 on host cells may contribute to the impairment of immune response which frequently leads to development of human cancers. P. gingivalis is known as one main etiologic agent of periodontal infection and expresses a variety of virulence factors. The aim of this study was to investigate if bacterial protein fractions, e.g. membrane and cytosolic proteins, of P. gingivalis up-regulate the immunoregulatory receptor B7-H1 in oral squamous cell carcinoma cells and human gingival keratinocytes.

Research Session and Clinical Innovation

Material and Methods: Squamous cell carcinoma cells (SCC25) and immortalized human gingival keratinocytes (IHGK) were seeded in culture plates and infected with bacterial fractions as well as with INF-c (1–1000 U/ml). After 24 and 48 h cells were harvested and prepared using Western blot and immuno-staining with an antibody against human B7-H1. Analysis was performed using digital imaging (Peqlab). Results: Low basal expression of the receptor B7-H1 on SCC25 and IHGK was demonstrated. Moreover the expression of B7-H1 protein in response to IFN-c was increased on both cell lines in dose-dependent manner. After infection with the P. gingivalis W83 membrane fraction the protein level of B7H1 receptor significantly increased to 51% in IHGK and 94% in SCC-25 cells, whereas the sonicated pathogen induced B7H1 protein expression to 37% (IHGK) and 57% (SCC-25 cells) above basal expression (p < 0.05). Conclusion: The results of this study demonstrated up-regulation of B7-H1 in oral epithelial cells by P. gingivalis and may help to elucidate the possible role of the immunoregulatory B7H1 in the immune evasion of this pathogen.

RCI06 Periodontal disease and resolution of inflammation: effects of bacterial lipopolysaccharide on apoptotic cell phagocytosis by macrophage subsets N. Balci, C. Zenobia, G. Hajishengallis Philadelphia/United States of America Aim: The clearance of apoptotic cells by macrophages is important for resolution of inflammation in chronic inflammatory diseases such as a periodontitis. Although much is known about inflammatory cell responses induced by lipopolysaccharide (LPS), little is known about its effects on phagocytosis of apoptotic cells by different subsets of macrophages. We aimed to investigate the effect of Porphyromonas gingivalis and Escherichia coli LPS on apoptotic cell phagocytosis by M1 and M2 macrophage subsets. Material and Methods: Mouse bone marrow-derived macrophages were polarized to M1 and M2 phenotype following treatment with M-CSF and GM-CSF, respectively, and incubated with P. gingivalis and E. coli LPS. Mouse bone marrowderived neutrophils were cultured at 37°C and 5% CO2 for 17 h and treated with staurosporine for 4 h to induce apoptosis. A flow cytometric method was used to measure phagocytosis of fluorescently labeled apoptotic neutrophils. Results: The phagocytosis of apoptotic neutrophils by macrophages was inhibited by P. gingivalis and E. coli LPS in M1 macrophages but not in M2 macrophages. LPS-stimulated M1 macrophages displayed increased production of pro-inflammatory cytokines (TNF, IL-1a, IL-1b) as compared with M2 macrophages. Consistent with previous reports, the proinflammatory effect of E. coli LPS was stronger than that of P. gingivalis LPS. Conclusion: The capacity of M2 macrophages for apoptotic cell phagocytosis is resistant to the inhibitory effects of LPS from oral or enteric bacteria. This suggests that M2 macrophages can contribute to the resolution of inflammation even in the presence of proinflammatory stimuli.


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Research session: Antimicrobials RCI25 Resolvin D2 prevents alveolar bone loss during experimental periodontitis by down-regulating immune responses G. Mizraji1, L. Shapira1, A.H. Hovav1, T.E. Van Dyke2, A. Wilensky1 1

Jerusalem/Israel, 2Cambridge/United States of America

Aim: Although bacterial plaque is the main etiologic factor in periodontal disease, periodontal destruction is caused by an excessive immune response. Recent data show that lipid mediators of inflammation such as resolvins can actively regulate resolution of inflammation, resulting in prevention of tissue destruction. Our aim was to characterize the mechanism by which resolvin D2 (RvD2) regulates immunological functions during experimental periodontitis. Material and Methods: Mice were treated with 0.5 lg of RvD2 either intraperitoneally or orally and experimental periodontitis was induced by oral infections with Porphyromonas gingivalis (Pg). Gingival tissues, maxillae, spleens and serum were collected at various time points (1, 8 and 42 days) following infection and analyzed for gingival leukocyte content, T-cell function, alveolar bone loss (ABL), RANKL and OPG expression and serum cytokines. Results: Treatment with RvD2 prevented ABL following experimental periodontitis. One day following infection, RvD2treated mice presented significantly lower numbers of total leukocytes, monocytes and macrophages in the gingiva, while no differences were found at day 8. This was accompanied by reduced serum TNF-a levels observed in the RvD2 group. Six weeks following infection, the gingiva of RvD2-treated mice exhibited decreased T cells, CD4+ T cells, lower expression of RANKL and higher expression of OPG. Moreover, restimulated splenocytes from the RvD2 group secreted less IFN-c in comparison to the control group. Conclusion: Regulation of innate immunity during experimental periodontitis with, RvD2 down-regulates the induction of the characteristic robust Th1-type immune responses, thus preventing ABL. These data highlight the potential therapeutic benefit of lipid mediators of inflammation in the treatment of periodontitis.

RCI26 Characterisation of a temperate phage residing in the genome of the anaerobic bacteria Fusobacterium nucleatum polymorphum ATCC 10953 M. Al-Zubidi, S. Gul, M. Spencer, A.S. Nepal, I. Douglas, A. Rawlinson, G.P. Stafford Sheffield/United Kingdom Aim: To study a temperate bacteriophage in the genome of Fusobacterium nucleatum polymorphum ATCC 10953. Specifically, to map the limits of the putative prophage and its influence on physiology and test its prevalence in humans. Material and Methods: To establish the limits of the prophage genome within Fusobacterium nucleatum polymorphum ATCC 10953, a combination of bioinformatics, PCR and sequencing


were conducted. To examine influence on physiology physiological responses of a closely related F. polymorphum strain lacking prophage was exposed to oxidative stress, increased pH and viability and growth compared, whilst prophage induction was also tested. In addition attempted purification of a potential lysis gene from the prophage with potential as a therapeutic. Furthermore, plaque samples from chronic periodontitis patients in Sheffield were screened for F. polymorphum and the occurrence of its prophage using PCR primers. Results: Despite growing faster under both acidic and alkaline conditions, the results highlighted that the strain that harbour the prophage is much less aerotolerant than the control strain. While 41/135 plaque samples (15 patients) tested for the presence of Fusobacterium nucleatum polymorphum, no bands associated with the prophage were present. The potential lysis gene was successfully cloned and expressed in E. coli and purification attempts continue. Conclusion: The putative prophage of Fusobacterium nucleatum polymorphum potentially reduces fitness of this organism, a fact more pertinent in light of our inability to detect it in the human population so far. This study provides new insight into how periodontal bacteria and prophages interact and affect bacterial fitness.

RCI27 Antimicrobial susceptibility of the JP2 and the NonJP2 genotype of Aggregatibacter actinomycetemcomitans, isolated from individuals of African and Non-African origin €glund R. Claesson, C. Ho Aberg, M. Granlund Ume a/Sweden Aim: To examine the antibiotic susceptibility of Aggregatibacter actinomycetem-comitans, a bacterial species associated with oral as wells as with extra-oral infections. Material and Methods: Isolates of A. actinomycetemcomitans, 33 of the JP2 genotype, which is highly leukotoxic, and 127 non-JP2 genotype isolates were included. Nine of the JP2 isolates were isolated from individuals of non-African origin. Among the non-JP2-genotype isolates 61 was isolated from persons living in Ghana and the remaining 66 from individuals living in Sweden. The antimicrobial testing was performed according to guidelines from the European Committee on Antimicrobial Susceptibility Testing (EUCAST) and included: metronidazole, amoxicillin, benzylpenicillin, azithromycin, cefotaxime, tetracykline, meropenem, levofloxacin, gentamicin, and trimethoprim-sulfamethoxazol. Results: Non-JP2-genotype isolates had ≥8 times higher MIC90–values than JP2-isolates for metronidazole and benzylpenicillin. In addition slightly higher MIC90 –value of metronidazole was noted for JP2 isolated in Africa. Among the nonJP2 isolates seven were highly resistant (MIC ≥ 256 mg/l). The MIC90–values for metronidazole and benzylpenicillin in nonJP2-genotype isolates were substantially higher than the clinical breakpoint defined by EUCAST for anaerobic bacterial species. None of the isolates produced beta-lactamase. All isolates showed low MIC-values for azithromycin, cefotaxime, tetracykline, meropenem, levofloxacin, gentamicin, and trimethoprim-sulfamethoxazol. MIC90 for amoxicillin was 2 mg/l. Conclusion: The JP2-genotype of A. actinomycetemcomitans seems to be more susceptible to several tested antimicrobials compared with the non-JP2-genotype of the bacterium. Clinical

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and 6 months post-treatment. Microbiome obtained by 16S rDNA amplicon sequencing.

Effect of nonsurgical periodontal therapy (with or without oral doxycycline delivery) on glycemic status and clinical periodontal parameters in patients with prediabetes: a short-term londitudinal randomized case–control study

Results: Both treatments resulted in improved clinical parameters. Sampled sites in the test group showed higher probing depth reduction than those in the control group. Subgingival microbiomes in the test group showed significantly lower similarity (Bray-Curtis Similarity Index) between the baseline and the 3-month-visit compared to the controls (p < 0.001, Independent Samples T-test), but not between baseline and the 6month visit. Also Principal Component Analysis showed a more distinct microbiome shift at 3 months in the test rather than in the control group. Genera Filifactor, Tannerella, Porphyromonas, Treponema, uncultured Clostridiales and Sinergistaceae were significantly reduced in their proportion after both treatments (p < 0.05, Wilcoxon Signed Ranks test), while the test group showed significantly higher reduction of these taxa at 3 months than the control group (p < 0.05, Mann–Whitney test). Genera Paludibacter, Fusobacterium and Parvimonas were reduced only in the test group.

F. Javed Rochester/United States of America Aim: The aim of the present short-term longitudinal randomized case–control study was to assess the effect of nonsurgical periodontal therapy (NSPT) (with and without oral doxycycline delivery) on glycemic status and clinical periodontal parameters in patients with prediabetes. Material and Methods: Sixty-six patients with prediabetes and periodontal disease were included. Characteristics of the study cohort [age, gender, socioeconomic status (SES) education status, duration of prediabetes, and type of treatment adopted for prediabetes management] were recorded. Patients were randomly divided into two groups (33 patients/group). In group 1, scaling and root planing (SRP) was performed, and in group-2, patients underwent SRP and oral doxycycline (100 mg) administration once daily for 15 days. In each group, the following parameters were investigated at baseline and after 3 months: (1) fasting blood glucose level (FBGL), (2) hemoglobin A1c (HbA1c), and (3) periodontal parameters [plaque index (PI), bleeding on probing (BOP), probing depth (PD), and clinical attachment loss (AL)]. Statistical analysis was performed using Student’s t test. Results: There was no significant difference in age, gender, SES, education status, and duration and treatment of prediabetes among individuals in groups 1 and 2. Three months postNSPT, FBGL and HbA1c were significantly reduced among patients in group 1 (p < 0.05) and group 2 (p < 0.05) compared to baseline. Three months post-NSPT, PI (p < 0.05), BOP (p < 0.05), and PD (p < 0.05) were significantly reduced among patients in group 1 (p < 0.05) and group 2 (p < 0.05) compared to baseline. There was no difference in clinical AL between the groups after 3 months of NSPT. Conclusion: NSPT (with and without oral doxycycline delivery) reduces hyperglycemia and periodontal inflammation in patients with prediabetes.

RCI11 Effects of non-surgical periodontal therapy with or without support of systemic antibiotics on the subgingival microbiome S. Bizzarro, M.L. Laine, M.J. Buijs, W. Crielaard, B.G. Loos, E. Zaura Amsterdam/Netherlands Aim: To assess the effects of non-surgical periodontal treatment with or without the support of systemic antibiotics on the subgingival microbiome. Material and Methods: 37 periodontitis patients (test group: N = 18 amoxicillin and metronidazole; control: N = 19) underwent non-surgical periodontal treatment. Clinical measurements and subgingival plaque samples (pooled sample from the deepest not furcated site in each quadrant) were obtained at baseline, 3

profiles

were

Conclusion: Both periodontal therapies resulted in improved periodontal status and in compositional shift in subgingival microbiome. The treatment with antibiotics showed a greater impact on the microbial shift and higher efficacy in reducing certain taxa.

RCI12 Effects of photodynamic therapy in chronic periodontitis treatment: a randomized clinical trial M. Segarra Vidal, D. Aguirre-Rueda, S. Guerra-Ojeda, A. Lopez, M.D. Mauricio, J.M. Vila, F. Alpiste Valencia/Spain Aim: To evaluate additional effects of photodynamic therapy (PDT) in basic treatment of chronic periodontitis, by analyzing clinical periodontal and bone metabolic parameters, as well as microbiological and inflammatory agents. Material and Methods: Forty patients with chronic periodontitis are recruited into two groups, control group (n = 20) are treated with scaling and root planning (SRP), and PDT group (n = 20) are treated with SRP + PDT. Records of periodontal plaque index, probing depth, recession, attachment loss, bleeding on probing and crevicular fluid volume are collected. Gene expression (RT-PCR) of periodontal pathogenic bacteria (Aa, Tf, Pi, Td, Pi, Cr) and IL-1b, IL-6, TNF-a, OPG and RANK-L levels (enzyme immunoassay) are determined in crevicular fluid. Samples are taken at baseline, 30, 90 and 180 days. Results: Periodontal treatments induce an improvement of clinical parameters (p < 0.001) without differences between groups. Except for Pi, bacteria gene expression of Aa, Pg, Tf, Td and Cr decrease with time in both groups (p < 0.05) but without differences between them. Both treatments diminish (p < 0.05) IL-1b and TNF-a levels but not IL-6 levels in a similar manner. Treatments do not modify OPG levels but decreases RANK-L levels. This effect is greater (p < 0.05) in the PDT group. Conclusion: Treatment with PDT + SRP does not improve the results of clinical, microbiological and inflammatory parameters obtained with SRP. Compared to SRP, PDT + SRP treatment decreases levels of RANK-L indicating an improvement in bone loss.


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Research session: Periodontal medicine

phosphoribosyltransferase in peripheral blood mononuclear cells were measured by quantitative real-time PCR.

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Results: We achieved a training duration of 214 44 min and a significant increase in cardiorespiratory fitness. Transcript levels of p16INK4a significantly decreased (p < 0.005) from baseline (0.0054 0.0044) to 6 months (0.0039 0.0038). Telomere length significantly increased (p = 0.002) in subjects with no or moderate periodontitis (n = 48) from baseline (3504 436 bp) to 6 months (3770 575 bp). In subjects suffering from severe periodontitis (n = 11) telomere length did not change over the observation period (3490 638 bp vs. 3364 442 bp; p = 0.43). In the uni- and multivariate analysis of baseline factors potentially modifying the positive effect of physical exercise on telomere length and p16INK4a expression periodontitis (beta = 0.272, p = 0.041) and pulse wave velocity (beta = 0.263, p = 0.048) were significantly associated with an attenuated telomere length increase over the observation period.

Periodontitis and incident diabetes: a 10-year prospective study L. Winning, C. Patterson, F. Kee, I. Young, G. Linden Belfast/United Kingdom Aim: To investigate the association between periodontal disease, periodontal pathogens and incident diabetes in a homogenous group of 60–70 year old Western European men. Material and Methods: A representative sample of dentate males in Northern Ireland underwent a detailed periodontal examination between 2001 and 2003. Examination included subgingival plaque sampling, which was subsequently analysed by quantitative real time PCR, to determine presence of periodontal pathogens. Men were followed up by annual questionnaire and for those reporting diabetes their practitioner was contacted to validate diabetes type, treatment and diagnosis date. Cox proportional hazard models were used to estimate the effect of periodontitis and the presence of the various periodontal pathogens on incident diabetes. Multivariate analysis included adjustment for age, smoking, hypertension, BMI, baseline cholesterol level, baseline C-reactive protein level, marital status and socioeconomic status. Results: A total of 496 men (Mean age 63.5 SD 3.0 years) were included in the analysis. 37 cases (7.5%) of incident diabetes were identified and 49 men (9.9%) died during follow up. The median follow up period was 9.3 years. Multivariate effect estimation through Cox proportional hazard models showed that low threshold periodontitis was significantly associated with an increased risk of diabetes HR = 2.23, 95% CI = 1.07–4.619, p = 0.03. The effect of high threshold periodontitis was not significant HR = 1.85, 95% CI = 0.63–5.48, p = 0.26. There were no notable associations between presence of periodontal pathogens and incident diabetes. Conclusion: There was evidence in this homogenous group of dentate 60–70 year old men that low threshold periodontal disease was significantly associated with an increased risk of incident diabetes.

RCI14 Severe periodontitis attenuated the beneficial effects of physical exercise on biological age J. Eberhard1, A. Melk1, U. Tegtbur1, D. Hilfiker-Kleiner1, €mme1, C. Eulert1, G. Saretzki2, A. Kerling1, A. Nelius1, M. Ho 1 1 1 1 €ntgen , M. K€ D. Strunk , D. Berliner , P. Ro uck , J. Bauersachs1, A. Hilfiker1, A. Haverich1, C. Bara1, M. Stiesch1 1

Hannover/Germany, 2Newcastle/United Kingdom

Aim: We addressed the question whether periodontitis affects telomere length and p16INK4a expression during a 6-months exercise training in middle-aged men. Material and Methods: 59 healthy men with a former sedentary life-style were included. Periodontal status was assessed using the AAP-CDC clinical case definitions. Subjects were advised for an exercise training of 210 min per week over a period of 6 months. Blood was sampled after overnight fasting at baseline and after 6 months and telomere length and p16INK4a transcription levels relative to hypoxanthine


Conclusion: We found that the presence of severe periodontitis attenuated the beneficial effects of exercise on biological age and may therefore also affect regenerative capacity.

RCI15 Tooth loss and bleeding on probing are both related to mortality risk as well as to myocardial infarction, heart failure and stroke in a large cohort with median follow up time of 16 years A. Holmlund1, L. Lind2 1

G€ avle/Sweden, 2Uppsala/Sweden

Aim: To investigate if oral health could predict all-cause mortality and cardiovascular disease (CVD), such as myocardial infarction (MI), stroke and heart failure (HF) in individuals referred for specialised treatment of periodontal disease. Material and Methods: Between 1980 and 2012, a full mouth investigation were performed in 9237 individuals, including pocket depth (PD), number of teeth (NT), bleeding on probing (BOP) and bone loss measured on x-ray. The unique personal number of all individuals was run against the Swedish cause of death register and the national hospital discharge register to obtain cause of death and non-fatal incidence of CVD using ICD-codes. Results: During a median follow-up time of 16.6 years (153,103 PYAR), 1635 individuals died. For 817 of these, the mortality was due to CVD. The numbers of events of fatal/nonfatal MI were 676, Stroke 546 and HF 303. After adjusting for age, sex and smoking in Cox propositional hazard analyses, the worst quintile of NT and BOP compared to the best one for all-cause mortality had a hazard ratio (HR) of, 2.08 (95% CI 1.60–2.29) and 1.92 (95% CI 1.60–2.29), respectively; for fatal/ non-fatal MI, HR was, 2.11 (95% CI 1.39–3.20) and 1.42 (95% CI 1.08–1.87); for stroke, 1.63 (95% CI 1.0–2.63) and 1.97 (95% CI 1.45–2.68); and for HF, 2.08 (95% CI 1.10–3.92) and 2.32 (95% CI 1.53–3.51). Conclusion: Tooth loss and bleeding on probing were predictors of all-cause mortality, as well as for fatal/non-fatal myocardial infarction, stroke and heart failure, suggesting a link between oral health and CVD.

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RCI16 Effects of periodontal treatment on endothelium, systemic inflammation and mitochondrial function M. Orlandi, S. Masi, D. Bhowruth, M. Parkar, I. Kingston, S. Hurel, N. Gkranias, J. Suvan, N. Donos, J. Deanfield, F. D’Aiuto London/United Kingdom Aim: Impaired endothelial function, assessed by flow-mediated dilation (FMD), has been reported in patients suffering from periodontitis compared to the healthy controls. The aim of this study was to investigate the contribution of mitochondrial function and systemic inflammation on endothelial dysfunction in patients with severe periodontitis. Material and Methods: 51 patients with periodontitis were randomly allocated to either intensive (IPT) or control periodontal therapy (CPT). Endothelial function was assessed by FMD of the brachial artery at baseline and 6 months after therapy. Serial blood samples were collected at baseline, 1, 7, 60 and 180 days after therapy and analyzed with Multiplex inflammatory and endothelial assays (Mesoscale, USA). Peripheral blood mononuclear cells (PBMC) were isolated and analyzed by flow cytometry for reactive oxygen species (ROS) production (DHR and MitoSOXTM Red), and mitochondrial membrane potential (JC-1; Invitrogen). Results: FMD improved in IPT patients compared to CPT after 6 months of therapy (p = 0.005). PBMC in IPT patients exhibited statistically significant lower mitochondrial ROS (m-ROS) production (p < 0.01) but not membrane potential compared to those in CPT patients after 6 months. A greater reduction in m-ROS was observed in lymphocytes (p < 0.05). Cellular ROS production (DHR) was lower in IPT compared to CPT patients after 6 months of therapy (p < 0.05). Serum levels of inflammatory and endothelial activation markers were reduced in the IPT patients compared to CPT (p < 0.05). These results were independent of age, gender, smoking and body weight differences. Conclusion: ROS production and systemic inflammation predicted changes in endothelial function of patients with periodontitis.

RCI17 Atherosclerotic cardiovascular disease is associated with periodontitis among 60,174 patients of a large dental school in the Netherlands N.G.F.M. Beukers, C.A.M. Drost, S.C. Roos, G.J.M.G. Van Der Heijden, A.J. Van Wijk, B.G. Loos Amsterdam/Netherlands Aim: To investigate the association between periodontitis and atherosclerotic cardiovascular diseases (ACVD), within the electronic health records of a dental school in the Netherlands (ACTA). Material and Methods: Data was extracted anonymously and retrospectively from the electronic database (Axium) at ACTA for patients ≥35 years of age. A patient was recorded as having periodontitis or not, based on documented treatment codes for periodontitis. Any “yes” answer in the medical health questionnaire for cerebrovascular accidents (CVA), angina pectoris (AP)


and/or myocardial infarction (MI) was used to label a patient as suffering from ACVD. Socio-demographic characteristics and putative risk factors for periodontitis and ACVD (age, gender, smoking, diabetes, hypertension, hypercholesterolemia, postal codes) were also extracted. Chi-square tests and multivariable logistic regression analyses were performed. Results: A total of 60,174 individuals were identified; more periodontitis patients (n/N; 4.7%) than non-periodontitis patients (n/N; 1.9%) reported current or past ACVD [OR 2.5 (2.3–2.8)]. After adjustment for the confounders, periodontitis remained independently associated with ACVD [OR 1.6 (1.4–1.8)]. Notably, hypertension showed the largest OR: 5.6 (4.9–6.4). Further analysis showed that periodontitis was also independently associated with CVA and MI, but not for AP [OR 1.6 (1.2–1.9), 1.6 (1.333–1.9), 1.2 (0.9–1.5) respectively]. Furthermore periodontitis was independently associated with ACVD in age groups of 36–65 and >65 years. Conclusion: Periodontitis is an independent significant risk for ACVD in this large sample of the Dutch population.

RCI18 Periodontal disease in patients with established rheumatoid arthritis; results from the Swedish epidemiological investigation of rheumatoid arthritis study K. Eriksson1, L. Nise2, A. Kats1, E. Luttropp1, A.I. Catrina2, J. Askling2, L. Jansson1, L. Alfredsson2, L. Klareskog2, K. Lundberg2, T. Yucel-Lindberg1 1

Huddinge/Sweden, 2Stockholm/Sweden

Aim: This study aimed to investigate the prevalence of periodontitis among patients with established RA in the Swedish Epidemiological Investigation of Rheumatoid Arthritis (EIRA) case–control study. Material and Methods: A linkage between the EIRA registry, consisting of 2740 RA patients and 3942 matched controls, and the Dental Health Registry (DHR) was performed. All EIRA participants (included between 1996 and 2009) answered a questionnaire on a broad range of issues, including smoking habits. The Swedish DHR, initiated in 2008, includes diagnostic- and treatment codes for numerous dental and orofacial conditions in citizens over the age of 20. To validate the diagnosis obtained from the DHR, dental records from RA cases (n = 48) and controls (n = 49) were requested. Results: In total, 86% of the EIRA participants (2343 RA cases and 3386 controls) were identified in DHR. The most frequent diagnostic codes observed were for gingivitis (33% of RA patients and 35% of controls) and periodontitis (33% of RA patients and 32% of controls). Furthermore, peri-implantitis prevalence was 4.7% in RA and 4.1% in controls. The risk for periodontitis increased by age and current smoking status, in both cases and controls. When validating periodontal diagnosis from DHR with the dental records, approximately 90% of the diagnoses among cases and 88% among controls were confirmed. Conclusion: Our data verify that smoking is a risk factor for the development of periodontitis, both in RA cases and controls. However, no evidence of increased prevalence of periodontitis was observed in patients with established RA included in the Swedish EIRA study.


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Research session: Diagnosis RCI19 Clustering of periodontitis: modeling of clinical and microbiological data in a Dutch cohort C. Delatola1, B.G. Loos1, E. Tsivtsivadze2, M.L. Laine1 1

2

Amsterdam/Netherlands, Zeist/Netherlands

Aim: To cluster periodontitis patients based on pre-treatment clinical and microbiological data using spectral clustering algorithms. Material and Methods: This retrospective study included 655 patients who visited the Department of Periodontology, ACTA for periodontal therapy in 1998–2006. Demographic, clinical (plaque, redness, swelling, pocket depth, attachment level, bleeding on probing, pus, mobility) and anaerobic culture data (Porphyromonas gingivalis – Pg, Peptostreptococcus micros – Pm, Fusobacterium nucleatum – Fn, Tannerella forsythia – Tf, Aggregatibacter actinomycetemcomitans – Aa, Prevotella intermedia – Pi, Campylobacter rectus – Cr) were extracted. The patients were randomly divided in two cohorts (modeling cohort, n = 328 and validation cohort, n = 327) and clustered using consensus-based spectral algorithms based on clinical and microbiological data. For cluster definition a 0.7 probability threshold was chosen. Results: Three distinct clusters (blue, yellow, red) were identified in the modeling cohort reaching 92% accuracy. The blue cluster (n = 96) was defined by low levels of the clinical parameters, colony-forming-units (cfu), %Pg, and high %Pm and %Fn. The yellow cluster (n = 80) showed the exact opposite from the blue cluster, and additionally, low % Tf. The red cluster (n = 126) was characterized by high %Pg and %Tf, redness, swelling, deep pockets and advanced attachment loss. Notably, the same clusters were identified in the validation cohort. The mean ages of the blue, yellow and red clusters were 44.7, 39.1 and 41.0 years, respectively, indicating that the clustering based on clinical and microbial data is independent of age. Conclusion: Mathematical techniques are helpful to cluster periodontitis patients in distinct groups with distinct characteristics. Traditional classification systems may have to be reconsidered.

RCI20 Stress-related biomarkers in salvia and serum of patients with periodontitis compared to healthy controls H. Haririan, O. Andrukhov, A. Moritz, X. Rausch-Fan Vienna/Austria Aim: Psychological stress is considered to be a risk factor for the development of periodontal disease but evidence is missing how stress influences the psychoneuroendrocrine system. The aim of the study was to identify stress-related biomarkers in saliva and serum of periodontally healthy controls and patients with periodontitis to find biochemical markers related to periodontal disease. Material and Methods: 56 patients with periodontitis and 44 periodontally healthy controls were included in the study. Stimulated whole saliva and serum were collected and analyzed by ELISA for the following biomarkers: brain-derived neurotrophic


factor (BDNF), adrenomedullin (ADM), calcitonin gene related peptide (CGRP), neuropeptide Y (NPY), substance P (SP) and vasoactive intestinal peptide (VIP). The collection was made before periodontal treatment after a full mouth periodontal score. Differences between groups were tested with student’s t-test. Correlations were calculated as Pearson’s correlation coefficient. Results: There were significant differences in salivary biomarker concentrations between periodontally healthy and diseased individuals for SP, NPY and VIP but no differences for BDNF, ADM or CGRP. Salivary SP, NPY and VIP significantly correlated with mean probing pocket depths in periodontitis patients. Salivary NPY and VIP significantly correlated with the inflammatory status expressed by bleeding on probing. In serum, all biomarker concentrations were similar in periodontal health and disease. Conclusion: The stress-related peptides SP, NPY and VIP could reflect stress as a risk factor in saliva of periodontitis patients on a biochemical level. These neuropeptides were also correlated to clinical parameters of periodontitis and could therefore be considered as potential disease biomarkers in saliva.

RCI21 The effect of periodontal status on oxidative stress biomarkers in patients with type 2 diabetes 2 € M. Altıngöz1, Sß. Kurgan2, C. Onder , M. Serdar3, N. Basßkal4, € ut€ M. Uyanık5, U. Unl€ urk6, M. G€ unhan2 1

Oral & Dental Health, Acıbadem Ankara Hospital, Ankara/ Turkey, 2Department of Periodontology, Ankara University Faculty of Dentistry, Ankara/Turkey, 3Medical Biochemistry, Acıbadem University, Ankara/Turkey, 4Department of Endocrinology and Metabolism Diseases, Ankara University Faculty of Medicine, Ankara/Turkey, 5Biochemistry Laboratory, /Turkey, 6Department of Cß orlu Military Hospital, Tekirdag Endocrinology and Metabolism Diseases, Kırklareli Government Hospital, Ankara/Turkey Aim: The study was performed to evaluate the effect of periodontal status on salivary, serum and urine levels of 8-hydroxydeoxyguanosine (8-OHdG), salivary and serum malondialdehyde (MDA), salivary and serum 4-hydroxynonenal (HNE), salivary and serum advanced glication end products (AGEs) and receptor for AGEs (RAGEs) as marker of oxidative stress, for type 2 diabetes mellitus patients with generalized chronic periodontitis (CP).

Material and Methods: 32 patients with type 2 diabetes and gingivitis (GDM), 35 patients with type 2 diabetes and CP (PDM), 28 patients systemically and periodontally healthy (HH) and 26 systemically healthy with CP patients (PH) were included in the study. Clinical periodontal parameters were recorded and saliva, urine, venous blood samples were collected from all patients. 8-OHdG, MDA, HNE, AGE and RAGE levels were evaluated in saliva and serum with ELISA. 8-OHdG levels were evaluated in saliva and urine with tandem mass spectrometry. Results: Salivary 8-OHdG levels were significantly higher in the periodontitis groups compared to the GDM and HH groups (p < 0.001); urinary 8-OHdG levels were significantly higher in the PDM group compared to the PH and HH groups (p < 0.001). Salivary MDA levels were statistically higher in PDM, GDM and PH groups compared to HH group (p < 0.05). Salivary HNE levels were statistically higher in PDM group compared to GDM group (p < 0.05). Plasma AGE levels were

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PDM > GDM > PH > HH and plasma RAGE levels were HH > PH > GDM > PDM respectively. Conclusion: According to our results; we can say that salivary 8-OHdG, urinary 8-OHdG, salivary MDA, salivary HNE, plasma AGE, plasma RAGE levels may be useful for evaluation of periodontitis and diabetes mellitus.

RCI22 Periodontal status over time among adults, aged 35–85 years, and the influence of smoking and socioeconomic factors in Dalarna County, Sweden. Cross-sectional studies 1983–2013 1 € K.A. Edman1, K. Ohrn , A. Holmlund2, B. Nordstr€ om1, D. Hellberg1 1 €vle/Sweden Falun/Sweden, 2Ga


and bleeding index) and GCF samples were collected from 3 representative sites: healthy (≤3 mm), deep nonbleeding (DNB) (≥6 mm) and deep bleeding (DB) (≥6 mm) using Periopaperâ at baseline, 3 and 6 months. Non-surgical periodontal treatment was provided after data collection at each time point as necessary. Colourimetric substrates were used to determine each enzyme level in GCF. Logistic regression analysis was used to evaluate the ability of enzyme profiles to predict 2 mm improvement in pocket depth. Results: 35 subjects have completed the 6-month study to date. All biomarkers were significantly higher in diseased sites compared to healthy sites. Using threshold values of MMP8 (2340 ng/ll), elastase (3000 ng/ll), cathepsin G (240 ng/ll), trypsinlike (320 ng/ll) and sialidase (243 ng/ll), logistic regression showed that a combination of all of them at base-line provided accurate predictions of treatment outcome for DNB sites (81%) and DB sites (87%). When just MMP8, elastase and sialidase were combined, prediction values were 81% and 84% for DNB and DB sites respectively. Individual enzymes failed to predict >61% of improvements at the threshold level.

Aim: The aim of this study was to investigate the prevalence of periodontal disease and the influence of smoking using data from four cross-sectional epidemiological studies in an adult population, 35–85 year of age in 1983, 2003, 2008 and 2013.

Conclusion: Signature profiles of enzymes provides a sensitive prediction of a site’s response to non-surgical periodontal treatment.

Material and Methods: A random sample of 1012–2243 individuals answered a questionnaire and was clinically examined including radiographs. Severity of periodontitis was classified into three categories depending on bone loss measured on x-rays; no; moderate or severe periodontitis. Complete data in the different study years were obtained from 78% to 52%.

RCI24

Results: The prevalence of severe periodontitis the different study years was 7% in 1983, 5% in 2003, 10% in 2008 and 7% in 2013. The increase between 2003 and 2008 was statistically significant as well as the decrease between 2008 and 2013 (p < 0.05). The prevalence of moderate periodontitis was 45% in 1983 and decreased significantly to 23% in 2003. In 2008 it was 16% and increased significantly to 35% in 2013 (p < 0.05). Calculus seen on radiographs increased significantly from 13% in 2003, 22% in 2008 and 32% in 2013. After adjustment for age, number of teeth and a number of socioeconomic factors, current/former smoking was the variable that correlated significantly with periodontal disease in all study years (odds ratios ranging from 2.53 to 3.22). In 2003 single living was also correlated to periodontis (OR 1.69 95%CI 1.21–2.38). Conclusion: Smoking was the overall strongest factor associated with periodontal disease and other socioeconomic factors showed to have limited impact periodontitis.

RCI23 A study of biomarkers in patients with periodontal disease S. Gul, I. Douglas, G. Griffiths, A. Rawlinson Sheffield/United Kingdom Aim: To assesses the ability of combinations of key host enzymes (MMP8, Cathepsin G, Elastase) and bacterial enzymes (Trypsinlike activity, Sialidase) in gingival crevicular fluid (GCF) to predict the outcome of treatment in patients with chronic periodontitis.

Plasma adiponectin levels in diabetics with and without periodontal problems N. Gkranias, R. Garcia Sanchez, F. D’Aiuto, J.E. Suvan, S. Hurel, S. Humphries, N. Donos London/United Kingdom Aim: The aim of this study was to measure plasma adiponectin levels in a population of T1DM and T2DM subjects and to assess whether periodontal health status, as expressed by BPE scores, is associated with the circulating levels of adiponectin. Material and Methods: 524 DM subjects (321 T2DM and 221 T1DM) were used for this analysis. The subjects received a basic periodontal examination (BPE) and venepuncture for blood sample collection. Quantitative human total adiponectin concentrations levels were determined using ELISA kits (Aviscera Bioscience, Inc. Santa Clara, USA). Results: There was a negative correlation between adiponectin levels and: age (r = 0.121; p = 0.005), waist to height ratio (r = 0.144; p = 0.001) and BMI (r = 0.230; p = 0.01) in the whole group and BMI in the T1DM group (r = 0.255, p = 0.01) and age in the T2DM (r = 0.184, p = 0.001) group. In addition significant differences in adiponectin levels (p = 0.014) were found in the whole DM group when comparing subjects with health/moderate periodontal disease (BPE 0–3) (4608 142 ng/ml) versus subjects with severe periodontal disease (BPE 4) (4065 167 ng/ml) or when performing a three subgroup comparison (BPE 0–3 vs. BPE 4 vs. Edentulous Group) (p = 0.03). Conclusion: In our mixed DM population periodontal health status, as expressed by BPE scores, was found to be associated with circulating levels of adiponectin. Furthermore, in the same population, plasma adiponectin levels were negatively correlated with age, waist to height ratio and BMI.

Material and Methods: 80 individuals participated in a 6-month longitudinal study. Full mouth clinical parameters (pocket probing depth, clinical attachment loss, plaque index


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Research session: Antimicrobials RCI25 Resolvin D2 prevents alveolar bone loss during experimental periodontitis by down-regulating immune responses G. Mizraji1, L. Shapira1, A.H. Hovav1, T.E. Van Dyke2, A. Wilensky1 1

Jerusalem/Israel, 2Cambridge/United States of America

Aim: Although bacterial plaque is the main etiologic factor in periodontal disease, periodontal destruction is caused by an excessive immune response. Recent data show that lipid mediators of inflammation such as resolvins can actively regulate resolution of inflammation, resulting in prevention of tissue destruction. Our aim was to characterize the mechanism by which resolvin D2 (RvD2) regulates immunological functions during experimental periodontitis. Material and Methods: Mice were treated with 0.5 lg of RvD2 either intraperitoneally or orally and experimental periodontitis was induced by oral infections with Porphyromonas gingivalis (Pg). Gingival tissues, maxillae, spleens and serum were collected at various time points (1, 8 and 42 days) following infection and analyzed for gingival leukocyte content, T-cell function, alveolar bone loss (ABL), RANKL and OPG expression and serum cytokines. Results: Treatment with RvD2 prevented ABL following experimental periodontitis. One day following infection, RvD2treated mice presented significantly lower numbers of total leukocytes, monocytes and macrophages in the gingiva, while no differences were found at day 8. This was accompanied by reduced serum TNF-a levels observed in the RvD2 group. Six weeks following infection, the gingiva of RvD2-treated mice exhibited decreased T cells, CD4+ T cells, lower expression of RANKL and higher expression of OPG. Moreover, restimulated splenocytes from the RvD2 group secreted less IFN-c in comparison to the control group. Conclusion: Regulation of innate immunity during experimental periodontitis with, RvD2 down-regulates the induction of the characteristic robust Th1-type immune responses, thus preventing ABL. These data highlight the potential therapeutic benefit of lipid mediators of inflammation in the treatment of periodontitis.

RCI26 Characterisation of a temperate phage residing in the genome of the anaerobic bacteria Fusobacterium nucleatum polymorphum ATCC 10953 M. Al-Zubidi, S. Gul, M. Spencer, A.S. Nepal, I. Douglas, A. Rawlinson, G.P. Stafford Sheffield/United Kingdom Aim: To study a temperate bacteriophage in the genome of Fusobacterium nucleatum polymorphum ATCC 10953. Specifically, to map the limits of the putative prophage and its influence on physiology and test its prevalence in humans. Material and Methods: To establish the limits of the prophage genome within Fusobacterium nucleatum polymorphum ATCC 10953, a combination of bioinformatics, PCR and sequencing


were conducted. To examine influence on physiology physiological responses of a closely related F. polymorphum strain lacking prophage was exposed to oxidative stress, increased pH and viability and growth compared, whilst prophage induction was also tested. In addition attempted purification of a potential lysis gene from the prophage with potential as a therapeutic. Furthermore, plaque samples from chronic periodontitis patients in Sheffield were screened for F. polymorphum and the occurrence of its prophage using PCR primers. Results: Despite growing faster under both acidic and alkaline conditions, the results highlighted that the strain that harbour the prophage is much less aerotolerant than the control strain. While 41/135 plaque samples (15 patients) tested for the presence of Fusobacterium nucleatum polymorphum, no bands associated with the prophage were present. The potential lysis gene was successfully cloned and expressed in E. coli and purification attempts continue. Conclusion: The putative prophage of Fusobacterium nucleatum polymorphum potentially reduces fitness of this organism, a fact more pertinent in light of our inability to detect it in the human population so far. This study provides new insight into how periodontal bacteria and prophages interact and affect bacterial fitness.

RCI27 Antimicrobial susceptibility of the JP2 and the NonJP2 genotype of Aggregatibacter actinomycetemcomitans, isolated from individuals of African and Non-African origin €glund R. Claesson, C. Ho Aberg, M. Granlund Ume a/Sweden Aim: To examine the antibiotic susceptibility of Aggregatibacter actinomycetem-comitans, a bacterial species associated with oral as wells as with extra-oral infections. Material and Methods: Isolates of A. actinomycetemcomitans, 33 of the JP2 genotype, which is highly leukotoxic, and 127 non-JP2 genotype isolates were included. Nine of the JP2 isolates were isolated from individuals of non-African origin. Among the non-JP2-genotype isolates 61 was isolated from persons living in Ghana and the remaining 66 from individuals living in Sweden. The antimicrobial testing was performed according to guidelines from the European Committee on Antimicrobial Susceptibility Testing (EUCAST) and included: metronidazole, amoxicillin, benzylpenicillin, azithromycin, cefotaxime, tetracykline, meropenem, levofloxacin, gentamicin, and trimethoprim-sulfamethoxazol. Results: Non-JP2-genotype isolates had ≥8 times higher MIC90–values than JP2-isolates for metronidazole and benzylpenicillin. In addition slightly higher MIC90 –value of metronidazole was noted for JP2 isolated in Africa. Among the nonJP2 isolates seven were highly resistant (MIC ≥ 256 mg/l). The MIC90–values for metronidazole and benzylpenicillin in nonJP2-genotype isolates were substantially higher than the clinical breakpoint defined by EUCAST for anaerobic bacterial species. None of the isolates produced beta-lactamase. All isolates showed low MIC-values for azithromycin, cefotaxime, tetracykline, meropenem, levofloxacin, gentamicin, and trimethoprim-sulfamethoxazol. MIC90 for amoxicillin was 2 mg/l. Conclusion: The JP2-genotype of A. actinomycetemcomitans seems to be more susceptible to several tested antimicrobials compared with the non-JP2-genotype of the bacterium. Clinical

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breakpoints specific for A. actinomycetemcomitans would aid in the decisions of which antibiotics that should be used when treatment of infections caused by A. actinomycetemcomitans is warranted.

RCI28 Changes in antimicrobial susceptibility of subgingival bacteria in acute periodontal lesions following systemic administration of sitacfloxacin A. Saito, S. Tomita, S. Kasai, Y. Ihara, K. Imamura, K. Ota, D. Kita, T. Nakagawa Tokyo/Japan Aim: To assess the effects of systemic administration of sitafloxacin on antimicrobial susceptibilities of clinical isolates from acute periodontal legions and to monitor the emergence of strains resistant to some antimicrobials. Material and Methods: Patients with acute phases of chronic periodontitis were subjected to clinical examination and microbiological assessment of their subgingival plaque samples by culture technique. Sitafloxacin was then administered (100 mg/day for 5 days) systemically. The clinical and microbiological examinations were repeated 6–8 days after administration. Susceptibilities of clinical isolates from acute sites to various antimicrobials were determined using the broth and agar dilution methods. When strains resistant to antimicrobials tested were isolated, a follow-up microbiological examination was performed. Results: From sampled acute sites in 30 participants, a total of 194 clinical isolates were obtained and identified. Among the antimicrobials tested, sitafloxacin was the most potent against the clinical isolates with a MIC range of 0.008–4 lg/ml before and after administration. Subgingival bacteria with low sensitivity to levofloxacin were isolated from 4 patients after sitafloxacin administration. At the follow-up sampling after approximately 12 months, levofloxacin low-sensitive bacteria were no longer identified. Conclusion: Sitafloxacin exhibited potent antimicrobial activity against majority of subgingival bacteria isolated from acute sites before and after its administration. It is suggested that the presence of the quinolone low-sensitive strains after sitafloxacin administration was transient, and they could not persist in the subgingival milieu during the maintenance therapy. It is necessary to longitudinally monitor susceptibility of subgingival bacteria to antimicrobials including sitafloxacin.

RCI29 Development and treatment of volatile compoundproducing oral biofilms in an in vitro flow system mez, S. Isabal, R. Leo n V. Blanc, M. Gonzalez, A. Soler, R. Go Cerdanyola del Valles/Spain Aim: The volatile compounds (VCs), mainly organic sulphur compounds (OSCs), which result from the oral bacterial metabolism, are the main cause of offensive breath odor. Since microbiological research of halitosis is very cumbersome in vivo, the aims of this in vitro study were: (1) to develop an oral biofilm growth model for measuring the qualitative and quantitative


changes in VCs and (2) to assess the effect of an anti-halitosis mouthrinse on the biofilms growth and on the VC production. Material and Methods: An artificial mouth system was used to grow two types of biofilms: A_Biofilm, composed of primary colonisers and B_Biofilm, composed of A_Biofilm plus Porphyromonas gingivalis and Prevotella intermedia. The vitality and structure of the biofilms were assessed using plate culturing and CSLM. OSC production was evaluated by Gas chromatography-mass spectrometry. Halitaâ mouthwash was used for the treatment of B_Biofilms. Results: The B_Biofilms presented greater thicknesses and total volumes when compared to the A_Biofilms, although the bacterial volume, the volume of live bacteria and the cfu/ml counts were greater in the A_Biofilms. With regard to VCs, the B_Biofilms showed a reduced diversity and an increased total VC concentration (increased OSC, aldehydes and ketones). The treated B_Biofilms showed a significant reduction in bacterial viability, a change in the distribution of species, an increase in VC diversity and a reduction in ketones and OSCs. Conclusion: This model allowed us to study different types of VCs produced by multispecies oral biofilms and to assess the anti-halitosis effect of a mouthrinse.

RCI30 Comparative analysis of the prevalence of tetracycline resistance genes in the microbiota of healthy and periodontitis patients A. Arredondo1, V. Blanc1, C. Mor2, J. Nart2, R. Le on1 2 Cerdanyola del Valles/Spain, Sant Cugat del Valles/Spain

1

Aim: The emergence of antibiotic resistant bacterial strains has become a world health problem with important economic implications. The aim of this investigation was to analyse and compare the prevalence of tetracycline resistance genes in the oral microbiota of both healthy and periodontitis patients. Material and Methods: Forty healthy and 40 periodontitis subjects were enrolled. Subgingival samples were taken with paper points and inoculated on selective media with tetracycline and incubated in anaerobiosis. The selected isolates were identified using rDNA16S gene sequencing. Eleven tetracycline resistance genes (tet genes), one erythromycin resistance gene (ermB) and the int gene were screened using multiplex PCR. Isolates were also screened for mobile genetic elements. Results: The results show that: (1) the patients with periodontitis had a greater bacterial load and a greater load of tetracycline resistant bacteria (2) from a total of 286 isolates a greater tetracycline resistance gene diversity was observed in healthy patients, (3) 25% of the isolates from diseased patients belonged to the Viridans Group Streptococci compared to 16% of isolates from healthy patients, (4) Tn916/1545 family of transposons were found in both patient groups. Conclusion: The tet(M) gene was the most prevalent in both patient groups. Approximately 15% of the microbiota showed tetracycline resistance. There exists a high prevalence of the tet (32) gene in periodontitis patients. The presence of Tn916/1545 family of transposons was observed.


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Research session: Dental implants 1 RCI31 Combining microCT and histology to improve dental implant ingrowth behavior assessment – a direct comparison of the two methodologies K. Becker1, F. Schwarz1, M. Stauber2, T. Beißbarth3 €ttingen/ D€ usseldorf/Germany, 2Br€ uttisellen/Switzerland, 3Go Germany

1

Aim: (1) Providing a method that automatically finds a histology slice in the microCT volume to facilitate direct comparison of both modalities. (2) Direct comparison of the bone to implant contact (BIC) values in the registered samples. Material and Methods: To find a histology slice within the respective microCT volume, the position and normal vector of the corresponding slice were computed through automated image registration. In principle, the implant contours and the bone tissue were segmented and subsequently matched using adapted mathematical optimization method. This bimodal registration was tested on n = 10 canine biopsies, obtained at 20 weeks after implant placement. BIC measures were performed manually by two independent observers and automated. Regression analysis was conducted to test the agreement of the respective 2D BIC measurements from the two modalities. Results: The histology slices were successfully and automatically found within the respective microCT volumes for all specimen. Direct comparison of the respective BIC measurements yielded that automated (median 0.82, 1.–3. Qu.: 0.75–0.85) and manual (median 0.61, 1.–3.Qu.: 0.52–0.67) BIC measures from microCT were significant positively correlated with histology (median 0.65, 1.–3. Qu.: 0.59–0.72) between the histology and microCT groups (R2manual = 0.87, R2automated = 0.75 (p < 0.001). Conclusion: The provided method allows for reliable registration and direct comparison of histology and micro CT.

RCI32 Randomized controlled clinical study evaluating two membranes for guided bone regeneration N. Naenni, D. Schneider, C. H€ammerle, J. H€ usler, R. Jung, D.S. Thoma Z€ urich/Switzerland Aim: To test whether two membranes are different regarding peri-implant guided bone regeneration in terms of clinical and radiological outcomes. Material and Methods: In 27 patients, 27 implants were placed in single-tooth gaps in the anterior area of both maxilla and mandible. All implants had a buccal dehiscence defect of at least 3 mm. These defects were augmented using demineralized bovine bone mineral and randomly covered with either a resorbable membrane (RES, n = 12) or a titanium-reinforced non-resorbable membrane (N-RES, n = 15). The horizontal thickness (buccally) of the augmented area was assessed (baseline). Following primary wound closure, a cone-beam computed tomography (CBCT) was taken. At 6 months, a second CBCT was performed, a full thickness flap elevated, and the horizontal thickness re-measured. Linear measurements were performed on CBCTs assessing the augmented area.


Results: At baseline, the clinical horizontal thickness at implant shoulder was 3.38 mm mean (SD = 0.51; RES) and 2.85 mm mean (0.63; N-RES). At 6 months, these values amounted to 1.95 mm (0.88; RES) and 2.85 mm (1.16; N-RES) and the changes were statistically significant (p < 0.001 KenwardRoger). High resolution CBCT analyses revealed a decrease from baseline to 6 months at the implant shoulder of a median 0.72 mm (mean 0.83 SD 0.82 RES) and a median of 0.07 mm (mean 0.15 SD 0.37 N-RES). These changes were statistically significant between the groups (p = 0.009 Wilcoxon). Conclusion: Both treatment modalities were clinically and radiologically effective in regenerating bone on the buccal side of dental implants but changes over time and differences between the groups were statistically significant.

RCI33 Additive manufacturing of TI6AL4V captures human trabecular bone structure to create constructs that affect osteoblast differentiation in a porosity dependent manner A. Cheng1, A. Humayun2, B.D. Boyan2, Z. Schwartz2 Atlanta/United States of America, 2Richmond/United States of America

1

Aim: The aim of this study was to characterize three-dimensional (3D) porous Ti6Al4V constructs fabricated by additive manufacturing from a human trabecular bone template using laser sintering, and evaluate biological response to these constructs. Material and Methods: 2D control and 3D porous Ti6Al4V constructs were manufactured using laser sintering to produce constructs with low, medium and high porosity (LP, MP, HP) with low and high trabecular bone detail (LD, HD). Material characterization included contact angle (2D only), micro-computed tomography, x-ray photoelectron spectroscopy, laser confocal microscopy, and scanning electron microscopy. MG63 cells were seeded (6 9 104 cells/construct) and harvested 24 h after confluence on tissue culture polystyrene to assess response. hMSCs were seeded (2 9 106 cells) on MP-HD constructs with and without collagen coatings and cultured for 8w in growth or osteogenic medium to assess mineralization. Results: Open porosity of constructs ranged from 41% to 76%. All constructs had similar surface micro- and nano-roughness after processing. Surface chemistry consisted mostly of O, C and Ti. 2D disks had a contact angle of 62°. MG63 cells had decreased DNA content and alkaline phosphatase activity and increased osteocalcin and BMP2 on 3D constructs in comparison to 2D. Vascular endothelial growth factor, BMP2 and BMP4 were highest on MP-HD constructs. Mineral content was observed on MP-HD constructs after 8w with and without the presence of a collagen coating. Conclusion: 3D Ti6Al4V constructs produced by additive manufacturing to mimic trabecular bone with varying porosity differentially affect osteoblast response and induce hMSC mineralization, even in the absence of osteogenic media supplements. Disclosure: ZS is a consultant for AB Dental.

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RCI34 Prevalence of peri-implant diseases in a large and randomly selected patient sample J. Derks, J. H akansson, J.L. Wennstr€ om, D. Schaller, C. Tomasi, T. Berglundh Gothenburg/Sweden Aim: The aim of this cross-sectional study was to assess the prevalence of peri-implant mucositis and peri-implantitis in a large and randomly selected patient sample. Material and Methods: Using the national data register of the Swedish Social Insurance Agency, patient files of 2765 patients (11,311 implants) were collected from more than 800 clinicians. 596 subjects, provided with 2367 implants, were randomly selected and attended a clinical examination 9 years after therapy. Examination included assessments of peri-implant probing depth and bleeding on probing (BoP). A radiographic examination was performed and changes of marginal bone levels were assessed relative to baseline radiographs retrieved from patient files. Implants and patients were diagnosed: (1) healthy, (2) mucositis or (3) peri-implantitis. Mucositis was defined as the presence of BoP without concommitant bone loss. Peri-implantitis was defined as the presence of BoP with concommitant bone loss. Different thresholds for bone loss were utilized. Risk indicators for mucositis and peri-implantitis were identified by multiple and multi-level analyses. Results: 61% of all implants exhibited BoP. On the patient level, the prevalence of mucositis and peri-implantitis ranged from 49% to 59% and from 18% to 28%, respectively, depending on the case definition. On the implant level, the prevalence of mucositis and peri-implantitis ranged from 46% to 51% and from 9% to 15%, respectively. Conclusion: Peri-implant diseases are common in patients provided with implant-supported restorations. Disclosure: Dr. Berglundh reports grants and personal fees from Dentsply Implants IH, outside the submitted work. Dr. Derks, Dr. Tomasi and Dr. Wennstr€om report personal fees from Dentsply Implants IH, outside the submitted work.

RCI35 Surgical therapy of peri-implantitis: 6 months clinical results of a multicenter RCT K. Jepsen1, S. Jepsen1, M. Sanz2, A. Ortiz-Vigon2, A. Pilloni3, B. Zeza3, B.G. Loos4, M.L. Laine4, D. Anssari Moin4, D. Wismeijer4, A.M. Roos-Jans aker5, S. Renvert5 1

Bonn/Germany, 2Madrid/Spain, 3Rome/Italy, 4Amsterdam/ Netherlands, 5Kristianstad/Sweden

Aim: The aim of this study was to evaluate the clinical outcomes of the use of porous titanium granules (PTG) for reconstructive surgery of peri-implantitis defects in comparison with open flap debridement (OFD). Material and Methods: In a multi-national, multicenter randomized controlled clinical trial, 63 patients (36 female, 27 male; mean age: 58.4 12.3 years), each contributing one 3 or 4 wall peri-implant osseous defect (≥270 degrees) were included using a parallel group design. Subjects had received non-surgical periodontal/peri-implant therapy. All defects were surgically treated by OFD using a titanium brush (TB) for implant surface


debridement. In addition 33 patients received PTG. Implants were not submerged and all patients were prescribed adjunctive systemic antibiotics (amoxicillin and metronidazole) for 8 days. Clinical outcomes (PPD, BoP, PuS, Plaque) were assessed by blinded examiners. Statistical analysis was performed by Stratified Wilcoxon rank-sum test and ANCOVA. Results: Both groups showed statistically significant improvements in all clinical parameters (p < 0.0001) between baseline and the 6 month evaluation. The PTG group showed a mean reduction in PPD (mesial/distal) of 3.2 mm (SD 1.7)/2.9 mm (SD 1.4) compared to 2.2 mm (SD 1.6)/2.8 (SD 1.7) in the OFD group. At 6 months the intergroup difference was statistically significant for reduction in PPD (p = 0.0352) and BoP (p = 0.0200) in favor of PTG. Conclusion: Significant improvements were obtained after both treatment modalities, however resolution of peri-implantitis was more pronounced in the test group.

RCI36 The effect of one time abutment placement on marginal bone levels and peri-implant soft tissues: a prospective randomized clinical trial A. Molina, I. Sanz, C. Martın, D. Herrera, M. Sanz Madrid/Spain Aim: To compare the effect of one time placement of the definitive abutment versus the placement of standard healing abutment in platform-switched titanium implants on soft and hard tissue changes. Material and Methods: Platform switched implants were placed in the posterior maxilla or mandible of partial edentulous patients. Implants were randomized to receive the final abutment at the moment or implant placement, or 6–12 weeks later. Final prostheses were delivered 2 weeks later. Clinical status of peri-implant tissues, radiographic assessment of vertical bone level changes (periapical radiographs), changes in soft tissues margin, papilla filling, patient related outcomes and adverse events were assessed at 6 and 12 months after loading. Results: Forty-two implants were placed in 26 partial edentulous patients, replacing single or multiple absent teeth. One implant was lost 1 week after insertion (overall survival rate: 97.6%). SS greater bone resorption from surgery to loading was observed for those implants submitted to abutment dis- and reconnection (BLoss surgery-loading: control group: 0.90 0.83 mm versus test group: 0.49 0.32 mm; p = 0.05). Periodontal clinical parameters (PD, mSBI, mPI) experienced SS increase from loading to 6 months, and remained stable up to 12 months, with no SSD between groups at any time point. An increase in papilla height was observed from loading to 12 months in all implants (Test: 0.96 mm, control: 0.99 mm). Conclusion: The connection and disconnection of healing abutments is associated with statistically significant increased bone loss during the healing period between implant placement and prostheses loading, when compared with no abutment removal.


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Clinical innovations: Periodontal regeneration RCI37 Periodontal regeneration versus extraction and prosthetic replacement of hopeless teeth with attachment loss to or beyond the apex. Costeffectiveness analysis P. Cortellini1, G. Stalpers1, A. Mollo2, D. Bonaccini1, M. Tonetti3 1

Firenze/Italy, 2Pistoia/Italy, 3Genova/Italy

Aim: To evaluate the cost-effectiveness of different treatments aimed at either saving or replacing hopeless single-rooted teeth with periodontal destruction to or beyond the apex. Material and Methods: 50 patients with severe periodontitis and 1 hopeless tooth were included in a randomized 5-year follow-up clinical trial. Twenty-five hopeless teeth were treated with periodontal regeneration, 25 controls were extracted and replaced with implant-supported crown (14), tooth-supported bridge (8), or Maryland bridge (2). One was not replaced. Clinical parameters were evaluated at baseline, 1 and 5 years. The following parameters were recorded: (1) number of visits, total chair-time (minutes), and time (months) for completion of active therapy (AT); (2) number of visits for the management of 5-year complications; (3) Actual costs of AT plus management of complications, calculated in euro and based on a representative fee schedule for Italian dentists. Results: At 5 years, total actual costs for periodontal regeneration averaged 1799 409 €. This compared with 3846 593 € for replacement with dental implants, 4686 522 € for tooth supported bridge and 2341 355 € for Maryland bridge. 92% of regenerated teeth survived and their complication-free survival rate (CFSR) was 84%. All replaced teeth survived with a CFSR of 83%. Cost-effectiveness analysis ranked: 1st regeneration of hopeless teeth (Value: 0.05007887); 2nd Maryland bridge (0.0405515); 3rd crown on single implant (0.02544946); 4th tooth supported bridge (0.02119812). Conclusion: Regeneration has the potential to change the prognosis of hopeless teeth, and its cost-effectiveness ratio is superior to any prosthetic replacement treatment.

RCI38 No adjunctive effect of bone replacement graft to the regenerative treatment of intrabony defects with enamel matrix derivative. A randomized, multicentre, practice based study M. Latronico1, G. Pellegrini1, M. Antonelli2, G. Chiarandini3, A. Delfino4, E. Farina4, R. Garbuio5, A. Martiniello6, J. Milioli7, P. Moratti8, N. Oteri9, M. Triches10, A. Tullini11, P. Cortellini12, M. Tonetti13 1 Imperia/Italy, 2Perugia/Italy, 3Figline Valdarno/Italy, 4Napoli/ Italy, 5Settimo Torinese/Italy, 6Cicciano/Italy, 7Ferrara/Italy, 8 Reggio Emilia/Italy, 9Messina/Italy, 10Torino/Italy, 11Bologna/ Italy, 12Firenze/Italy, 13Genova/Italy

Aim: Objective of this multicentre RCT was to compare minimally invasive surgical technique (MIST) in periodontal regeneration supported by enamel matrix derivative (EMD) or EMD plus bone replacement graft (BRG).


Material and Methods: 120 deep intrabony defects in 120 chronic periodontitis patients were randomly treated with MIST either using EMD + BRG (test) or EMD alone (control). Depth of intrabony component and bony walls missing were recorded during surgery. The depth of the intrabony component was 5.33 1.84 5.38 1.71 and mm in test and control group, and the missing walls were similar in both groups. All patients underwent a 1-year periodontal supportive therapy program. Results: Primary wound closure was achieved in all patients at the end of surgery. Wound failure occurred in 17.4% of control and in 30.8% of test subjects at suture removal; after 1 year follow up residual PPD was 3.51 1.23 and 3.67 1.03 mm, CAL gain 3.42 2.22 and 3.24 2.41, REC increase 0.62 1.08 and 0.90 1.50 and PPD improvement 4.03 1.96 and 4.06 2.07 mm in test and control groups. Differences between test and control did not reach significance. Defect morphology (residual bony walls) did not influence outcomes. Stratifying the sample by baseline pocket depths, a tendency towards a better outcome in deeper pockets was observed in the test group. Conclusion: This study showed that periodontal regeneration with MIST is a safe and predictable therapy for intrabony defect and that the addition of BRG to EMD does not change the final outcome in terms of CAL gain, REC increase and PPD reduction.

RCI39 Is the benefit of periodontal regeneration compared to papilla preservation flaps dependent on the depth of the intrabony component? Individual patient data (IPD) meta-analysis of 6 randomized clinical trials S. Cortellini1, M. Tonetti2, P. Cortellini1 1

Firenze/Italy, 2Genoa/Italy

Aim: To evaluate the efficacy of periodontal regeneration with papilla preservation flaps (PPF) compared to PPF alone in intrabony defects of different depth. Material and Methods: The original data of 6 multicentre trials were pooled in a database and analysed. 512 defects treated with PPF with or without regenerative materials were stratified according to the baseline depth of the intrabony component (INFRA), as shallow (≤3 mm) mid (4–6 mm) and deep (≥7 mm). Results: Overall, at 1 year, regeneration resulted in greater clinical attachment (CAL) gain (3.6 2.0 mm vs. 2.5 1.5 mm, p < 0.004) and pocket depth reduction (PD Red, 4.5 2.2 mm vs. 3.5 1.7 mm, p < 0.003) than flap alone. These outcomes were confirmed in the clusters of mid (CAL gain 3.3 1.5 mm vs. 2.4 1.4 mm; PD Red 4.1 1.7 mm vs. 3.2 1.6 mm, p < 0.001) and deep defects (CAL gain 4.5 2.7 mm vs. 2.8 1.8 mm; PD Red 5.6 2.8 mm vs. 4.2 1.9 mm, p < 0.001). Conversely, no significant difference between test and control was observed in shallow defects in terms of CAL gain (2.4 1.4 mm vs. 1.9 1.4 mm, p = 0.150) and PD Red (3.1 1.4 vs. 2.9 1.3, p = 0.569). Differences in gingival recession between test and control did not reach statistical significance in any of the groups.

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Conclusion: No added benefit was observed from the use of PPF and regenerative materials above PPF alone in shallow intrabony defects, while in mid and deep defects the use of regeneration consistently resulted in significant clinical improvements.

RCI40 13-year-results following GTR therapy in intrabony defects using autogenous platelet concentrate L. Tabenski1, F. Cieplik1, P. Bosse2, K. Hiller1, G. Schmalz1, W. Buchalla1, M. Christgau1 1

Regensburg/Germany, 2Munich/Germany

Aim: Investigation of the long-term clinical outcomes following guided-tissue-regeneration (GTR) in deep intrabony periodontal defects and of the additional influence of autogenous-plateletconcentrate (APC). Material and Methods: In 25 patients, two deep contralateral intrabony defects were treated with b-tricalcium-phosphate (TCP) and a bioresorbable GTR-membrane. Using a splitmouth-design, APC was additionally applied to the root surfaces and the TCP-granulate in the test defects. Long-termclinical-results were recorded by a blinded examiner 13 years after regenerative therapy and compared to the baseline and 1-year-situation. Furthermore, tooth-survival-analysis was performed. Results: After 13 years, 22 patients were available for toothsurvival-analysis. In the test group 81.8% and in the control group 86.4% of the teeth were still in-situ. Lost teeth were extracted for prosthodontic reasons. For clinical split-mouth analysis, 15 patients could be re-examined. At baseline, the median clinical attachment loss (CAL) was 10 mm in test sites and 12 mm in control sites. While both groups showed a statistically significant reduction to CAL = 6 mm after 1 year, CAL slightly increased again to 7 mm after 13 years. This change was not statistically significant. At no time, statistically significant differences could be found between test and control sites. After 13 years, bleeding on probing had also increased again in both groups compared to the 1-year situation. Conclusion: Within the limits of the present study, the longterm data indicate that the clinical healing results following GTR-therapy can be maintained over a 13-year-period. However, the additional application of APC did not show an additional influence on the short- and long-term healing outcomes (supported by Robert-Mathys-Foundation, Bettlach, CH).

RCI41 Treatment of intrabony defects following application of enamel matrix derivative or platelet rich plasma C. Yenigun, G. Cakar, S. Dirikan Ipci, S. Yılmaz Istanbul/Turkey Aim: The aim of this present study was to compare the effectiveness of enamel matrix derivative (EMD) and platelet rich plasma (PRP) in the regenerative treatment of human intrabony defects.


selected. Each of the patients was treated with either EMD (Group A) or PRP (Group B). Prior to surgical treatment and at 12 months, plaque and sulcus bleeding indices, PD, recession, relative attachment and bone levels were measured. Results: Favourable clinical outcomes in soft and hard tissue measurements were achieved in both groups when compared to baseline (p < 0.01). Considering the deepest site of the defects, Group A and Group B presented a mean PD reduction of 3.17 1.22 mm and 3.18 1.26 mm, recession of 1.35 0.98 mm and 1.33 1.11 mm, attachment gain of 1.83 0.98 mm and 1.84 1.26 mm, respectively. Evaluation of the hard tissue findings revealed that the mean clinical bone gains in Group A and Group B were 1.53 0.89 mm and 1.60 1.32 mm, respectively. Intergroup differences were insignificant in terms of all evaluated parameters (p < 0.05). Conclusion: It can be concluded that both biologic mediators present similar results and can be used in the treatment of shallow intrabony defects.

RCI42 Intrabony defect treatment: enamel matrix derivative intramarrow penetration A. Crea1, C. Littarru1, G. Vittorini Orgeas1, G. Paolantoni1, D. Capri1, C. Lajolo1, I. Bignozzi1, L. Landi1, R. Saviano1, G. Deli1, D.N. Tatakis2 1

Rome/Italy, 2Columbus/United States of America

Aim: This randomized controlled trial examines the outcomes of regenerative therapy of deep intrabony defects when Enamel Matrix Derivative (EMD) is used with or without intramarrow penetration (IMP). Material and Methods: 50 chronic periodontitis patients, each presenting with one intrabony defect ≥3 mm deep, were enrolled. Defects were randomly assigned into control group (EMD alone) or test group (EMD + IMP). Papilla preservation flaps were raised and, before the root conditioning, the cortical wall of the intrabony defect was penetrated using a round bur (test group only). Clinical parameters, including bone sounding (IBD), and radiographic measurements were recorded immediately prior to surgery and at 12 months postoperatively. Hygiene recalls were provided. Results: 50 defects were surgically treated and 45 were included in data analysis (Control: n = 21; Test: n = 24) Surgeries and postoperative course were uneventful for all patients. At 12 months, no statistically significant differences in CAL gain, PPD reduction, IBD reduction, recession increase, radiographic defect depth (rDD) or width reduction were found between the two groups. 62% of control and 54% of test sites gained ≥2 mm of attachment; no sites lost attachment. Complete closure of the radiographic angle occurred in 38% and 13% of the control and test group defects, respectively. Conclusion: Both treatments were effective in terms of CAL gain, and PPD, IBD and rDD reduction, with minimal recession increase. The results of the present investigation suggest that addition of IMP to an EMD procedure may not result in significant improvement of clinical outcomes when treating intrabony defects.

Material and Methods: A total of 99 intrabony defects with an associated probing depth (PD) of ≥5 mm and an intrabony component of ≥2 mm following non-surgical therapy were


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Research session: Dental implants 2 RCI43 A retrospective evaluation of aesthetic outcomes for single-tooth implants in the anterior maxilla N. Boardman, S. Chen, I.B. Darby Melbourne/Australia Aim: To investigate objective and patient-centred aesthetic outcomes for single tooth implants in the anterior maxilla. Material and Methods: Ninety-eight patients with a mean age of 51.2 13.8 years were included in this retrospective study. A total of 98 maxillary anterior single tooth implant crowns with a mean functional time of 68.1 months (range 12–245) were evaluated. Esthetic outcomes were measured by PES and WES scores. Subjects were also asked about their satisfaction with the implant. Statistical analysis was performed using the Mood’s median and stepwise logistic regression with backwards elimination to determine the effect of multiple variables on aesthetic outcome. Results: The median PES was 11% and 94% of implants were deemed aesthetically acceptable. The median WES was 9% and 98% of implants were deemed aesthetically acceptable. The PES was positively influenced by the use of a connective tissue graft (CTG), adding 1 to the score (p = 0.002) and negatively influenced by membrane use (p = 0.026). Flapless techniques employed as part of an immediate implant placement protocol yielded better outcomes compared to flapped sites (p = 0.017). Immediate implant placement demonstrated greater variability in outcomes compared to early implant placement. Patients were generally very satisfied with the appearance of the final implant. Conclusion: Satisfactory objective and patient-reported aesthetic outcomes were achieved with dental implants replacing missing single teeth in the anterior maxilla. The use of CTG improved the aesthetic outcome mainly by increasing the alveolar process contour. Less variation in outcomes was observed with early (type 2) placement compared to immediate (type 1 placement).

RCI44 A comparative study of bilateral maxillary sinus lift: autogenous bone versus alloplastic grafts 2 U. Garagiola1, E. Del Rosso1, C. Maiorana1, G. Szabo 1

Milano/Italy, 2Budapest/Hungary

Aim: Two different graft materials, b-tricalcium phosphate (b-TCP) and autogenous bone, were used in the same patient. The aim of this study was to determine whether donor site morbidity could be avoided by using pure-phase b-TCP.

were analyzed as percentages of the total. The mean percentage bone areas were 36.47% 6.9% and 38.34% 7.4%, respectively; the difference was not significant (p = 0.25). The autogenous bone was initially less visible than the b-TCP, but new bone formation was clearly observed for both materials. The rate of graft resorption was lower on the experimental side than on the control side. The mean graft area percentages were 13.95% 5.38% and 8.47% 3.17%, and the difference was highly significant (p < 0.001). Conclusion: Comparisons with other studies reveal that b-TCP is a satisfactory graft material for maxillary sinus floor augmentation, even without autogeneous bone.

RCI45 A multivariate analysis on implant treatment outcome of cemented versus screw-retained reconstructions in patients with and without history of periodontitis G. De Moyer Geraardsbergen/Belgium Aim: This study evaluated Straumann implant treatment outcome after 4–5 years follow-up, with respect to survival and bone loss related to restoration type, either screw (SR) or cement retained (CR) and patient’s history of periodontitis (PH+ or PH ). Material and Methods: Partially edentulous patients, treated in a periodontal practice and under supportive therapy, were recalled for clinical/radiographical analysis by an independent evaluator (GDM). Implant survival, crestal bone loss (BL) from the restoration level and impact of explanatory variables (SR, CR, PH+, PH ) were evaluated using multivariate statistical analysis on implant level. Results: 91 implants in 44 patients [27 women; 17 men; mean age 62 years (SD 10.29; range 26–77)] were evaluated. Overall Implant survival was 98.9%. The mean BL was 1.5 mm (SD 0.9; range 0–4.2) for CR versus 0.8 mm (SD 1.5; range 0–7.1) for SR. In PH+ patients, bone loss was 1.5 mm (SD 1.6; Range 0–7.1) vs. 1.0 mm in PH (SD 1.0; range 0–3.3). Multivariate analysis revealed a significant difference between PH+ and PH , and between SR and CR. With more bone loss found for PH+ (0.6 mm difference; p = 0.032) and CR (0.8 mm difference; p = 0.008). Conclusion: Implant survival was not affected by restoration type or periodontal history. However, both factors were identified as risk factors for crestal bone loss. Implants installed in patients with a history of periodontitis, supporting cementretained reconstructions, showed the worst clinical conditions.

Material and Methods: Bilateral sinus grafting was performed on 20 selected patients; b-TCP was used on the experimental side. Autogenous bone was used on the control side. In each patient, one side was randomly designated the experimental side. Eighty bone biopsy specimens were taken at the time of implant placement.

RCI46

Results: Histologically and histomorphometrically, there was no significant difference between the experimental and control grafts in terms of the quantity and rate of ossification. For each histologic sample, the total surface area, the surface area that consisted of bone, and the surface area that consisted of graft material were measured in mm2, and bone and graft material

Strasbourg/France


Long-term prospective cohort study on dental implants: clinical and microbiological analysis H. Tenenbaum, O. Bogen, R. Elkaim, J. Davideau, O. Huck

Aim: The aim of the present prospective cohort study was to evaluate clinical and microbiological data of dental implants after at a mean follow-up of ˃10 years.

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Material and Methods: 110 patients and 232 implants were included at baseline. 52 patients and 108 implants could be evaluated at the final examination. Clinical parameters included plaque index, gingival index, sulcular bleeding index, pocket depth and clinical attachment level. Sub-gingival microbial samples were analyzed using a DNA Checkerboard technique. Results: The mean follow up time was 10.8 1.7 years (range: 8–13.8 years). Plaque index was respectively 0.47 0.53 at baseline, 0.57 0.41 at 1 year and 0.49 0.51 at the final examination. Gingival index was respectively 1.08 0.22 at baseline, 1.07 0.38 at 1 year and 0.62 0.48 at the final examination. Sulcular bleeding index was respectively 0.15 0.14 at baseline, 0.21 0.28 at 1 year and 0.20 0.23 at the final examination. Probing depth was respectively 2.74 0.61 at baseline, 3.00 0.62 at 1 year and 2.68 0.86 at the final examination. Clinical attachment level was respectively 3.74 0.88 at baseline, 4.10 0.83 at 1 year and 3.96 0.98 at the final examination. A great variability was observed regarding the different bacterial species with a large amount of periodontal pathogens detected at the final examination. Conclusion: 78.7% of implants and 71.2% of the patients were considered as success in the present prospective cohort study after a mean follow-up of 10.8 years.

RCI47 Zoledronic acid for guided bone regeneration in osteoporotic conditions N. Mardas1, J. Busetti2, J.A.P. De Figueiredo2, L.A. Mezzomo3, N. Donos1 1 London/United Kingdom, 2Porto Alegre/Brazil, 3Santa Catarina/ Brazil

Aim: To evaluate histologically bone healing of critical size calvarial defects (CSD) following Guided Bone Regeneration (GBR) in healthy, osteoporotic and osteoporotic treated with Zoledronic Acid (ZA) rats. Material and Methods: Experimental osteoporosis was induced by ovariectomy (ov) and calcium-deficient diet in 16 female, 6-month old Whistar rats. Eight ov rats were treated with a single injection of Zolendronic Acid (T1) and 8 ov rats received no treatment (T2). Another 8 rats were used as healthy controls (C). At 7 weeks following osteoporosis induction, a 5.0 mm in diameter CSD was created in each parietal bone. One defect was left untreated while the contralateral defect was treated with a double microporous Teflon membrane. The animals were sacrificed after 60 days. New bone formation (NB) was assessed in 3 central un-decalcified sections and expressed as % of the whole defect area. Results: NB in the GBR treated defects (mean % SD) was 95.8% 9 in T1, 78.3% 14.4 in T2 and 90.1 26.2 in C. NB in the untreated defects was 51.6% 39.5 in T1, 10.8% 17.5 in T2 and 15.7 12.1 in C. Hierarchical analysis of variance showed that treatment with Zoledronic Acid (p < 0.001) and the use of membrane (p < 0.01) significantly increased new bone formation. Conclusion: Teflon microporous membranes for GBR predictably promote bone healing. Zoledronic Acid Treatment for the treatment of osteoporosis may further improve new bone formation following GBR in osteoporotic conditions.


RCI48 Aesthetics, patient satisfaction and impacts of single tooth implants after at least 1 year in function S. Shahdad, A. Gamboa, I. Apostoulous, E. Lynch, E. Gamble, G. Ioannidis, R. Pawar, J. Makdissi London/United Kingdom Aim: To evaluate aesthetic outcome, patient satisfaction and impact of single tooth implant restorations placed in the maxillary aesthetic zone. Material and Methods: Patients with a single-tooth implant crown in the aesthetic zone, treated at The Royal London Dental Hospital since 2006 with at least 12 months post-loading, were invited to enter this study. Hydrophyllic implants were placed with or without simultaneous guided bone regeneration using deproteinized bovine bone and porcine collagen membrane. Outcomes measures included the Pink Esthetic score (PES), the White Esthetic Score (WES) and were independently scored by an experienced prosthodontist, periodontist and an orthodontist. Additionally, patient-based twelve formulated questions on patient satisfaction and the Oral Health Impact Profile (OHIP) were used. Descriptive statistics was used and the 95%CI considered. Results: Data was available for 60 implants which had been in function for 13–90 months (mean 42 m). Mean age was 33.1 (SD = 10.8). Mean PES was 11.2 (SD = 1.6) with 83% scores above 10. Mean WES was 8.5 (SD = 1.1) with 97% scores above 6. Patients reported high satisfaction (78–93%) to majority of the questions, and “appearance of the gums” ranked lowest with only 78% patients satisfied. Mean OHIP was 6.7 (SD = 7.3). Psychological discomfort was the highest impact reported (17%). Conclusion: There was a high prevalence of good aesthetics, patient satisfaction and low OHIP impacts in this cohort of patients.

Clinical innovations: Implants 1 RCI49 Digital implant planning with 3D printers and CBCTS in guided surgery and bone graft procedures F. Vidal, R. Vidal Rio de Janeiro/Brazil Aim: The aim of the present study is to present a novel digital implant planning protocol in which cone beam CTs, computer assisted design (CAD) software and desktop (domestic) 3D printers are used to plan implant positioning, design digital wax ups and manufacture surgical templates, allowing more accurate surgical procedures and predictable prosthetic results. Material and Methods: 2 clinical cases treated according to a fully digital implant planning protocol are presented. Cone beam CTs were obtained and images were imported in DICOM extension. Digital wax ups were designed using the 3D Maxâ software and after the prosthesis designs were approved, ideal implant positions were determined. In one of the cases, autogenous bone graft was needed previously to implant placement due to insufficient bone width. In this case, a prototype was


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printed and used to allow an easier adjustment of the bone block. Surgical templates were designed according to a prosthetically driven concept, in order to allow more accurate implant placement. The surgical template digital files were imported and a desktop 3D printer (UltimakerTM) was used to manufacture the templates with a biocompatible polymer. After the perfect fitting of the templates was confirmed, implants were placed following the surgical protocols recommended by the implant manufacturer. The final restorations were built using a CAD/CAM system (Neoshapeâ) and metal free frameworks. Results: Both cases healed uneventfully. 1 year follow up showed healthy peri-implant tissue and favourable esthetic and functional results. Conclusion: Digital implant planning and 3D printers are useful tools, allowing more accurate surgeries and predictable treatment outcomes.

RCI50 Large size ridge defects: early healing outcomes following GBR B. Leblebicioglu, M. Burashed, L. Alssum, A.C. Gross, T.D. Eubank, L. Christian, V. Yildiz, D.N. Tatakis Columbus/United States of America Aim: To determine early healing outcomes following ridge deficiency treatment by guided bone regeneration (GBR). Material and Methods: Sixteen non-smokers (60 4 years; 9 males) presenting large size defects (≥2 adjacent missing teeth) were treated with GBR (particulate allograft + membrane). Preand post-surgical ridge defect size was determined. Clinical evaluation was recorded at surgery, 1 week, 1 and 4 months. Wound fluid was collected from wound edges and quantified (volume). Repeated measures ANOVA, Spatial Power Covariance Structure and Spearman correlation analyses were used. Results: Primary wound closure was obtained in 94% of sites. Wound opening, limited to the crest, was common at week 1 (88% of sites), with 3.8 0.7 mm [median = 3 (0–10) mm] membrane exposure. Four sites presented minor exposure at 4 months. Average ridge width gain was 2 0.7 mm [median = 2 ( 3 to +7) mm]; most gain observed in middle defect area. Average ridge height gain was 1 0.7 mm [median = 1 ( 6 to +5) mm]. 53% of sites gained ≥2 mm width (p = 0.02) while 47% of sites gained ≥2 mm height (p = 0.06). 30% of sites that gained ≥2 mm width maintained/ gained height. Ridge width size was correlated with wound opening size (r = 0.329, p = 0.02) but not with the amount of wound fluid. The amount of wound fluid was correlated with opened wound (r = 0.457, p = 0.005) but not the size. Conclusion: Within the limits of this study, early wound opening is common following GBR for large size ridge defects; the associated wound fluid volume increases likely reflect the ensuing heightened local inflammatory response. Early wound opening may affect ridge width outcomes.

RCI51 Esthetic, clinical and patient centered outcomes of immediately places implants (type 1) and early placed implants (type 2): Preliminary 3-month results of an ongoing randomized controlled clinical trial G. Huynh-Ba1, D.J. Meister2, A.O. Hoders1, B.L. Mealey1, M.P. Mills1, T.W. Oates1, D.L. Cochran1, C.A. Mcmahan1 1

San Antonio/United States of America, 2Nashville/United States of America Aim: The objectives of this study were to compare (1) esthetic, (2.) clinical and (3) patient centered outcomes following immediate (Type 1) and early implant placement (Type 2). Material and Methods: Thirty-eight subjects needing a single extraction (premolar to premolar) were randomly allocated to Type 1 or 2 implant placement. Three months following permanent crown insertion, evaluation of (1) Esthetic outcomes using soft tissue positions, and the pink and white esthetic scores (PES/WES), (2) Clinical performance using probing pocket depth (PPD), modified plaque index (mPI) and modified sulcus bleeding index (mSBI) around each implant and (3) Patient satisfaction by means of a questionnaire using a visual analogue scale (VAS) was recorded. Results: Thirty-two patients completed the 3 months followup examination (Type1, n = 17; Type 2, n = 15) with a 100% implant survival rate. Type 1 implants lost 0.54 0.24 mm of midfacial soft tissue height while Type 2 implants lost 0.47 0.25 mm (p > 0.05). The papillae height on the mesial and distal was reduced about 1 mm following both procedures. The PES/WES scores following Type 1 implant placement amounted to 13.7 0.6 and 12.5 0.7 in the Type 2 group (p > 0.05). PPD, mPI, mSBI were low in both groups (p > 0.05). Patient centered outcomes failed to demonstrate any statistical difference between the two cohorts. Conclusion: Three months following final crown delivery, there were no significant differences in esthetic, clinical and patient centered outcomes following Type 1 and Type 2 implant placement. On the short-term, one may achieve good optimal esthetic and clinical results irrespective of these two placement protocols.

RCI52 Three-year results of a randomized clinical trial comparing short and long implants for posterior single-tooth replacement P. Sahrmann, N. N€anni, U. Held, T. Truninger, T. Attin, C. H€ammerle, R. Jung, P. Schmidlin Z€ urich/Switzerland Aim: To test the hypothesis that short implants are clinically as successful as long implants when used to support single crowns. Material and Methods: Ninety-six patients in need of implant supported single crowns in the posterior segments of both jaws were included. Patients were randomly allocated to receiving either a 6 mm (test) or a 10 mm (control) long implant. Implants were loaded with single crowns after 10 weeks. Survival rates, number of pockets >4 mm, Bleeding-on-Probing


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and bone level changes using standardized radiographs were assessed by two independent examiners. Longitudinal intragroup analyses were performed (Wilcoxon signed-rank test) and intergroup comparisons at different time points (Mann–Whitney U test). The effect of confounders on the marginal bone level was tested by multiple regression. The level of significance was set at p < 0.05 for all tests. Results: 47 test and 48 control implants were initially loaded. After 3 years 40 test and 38 control implants were available. Though one short implant was lost during the second year of loading, no significant difference for implant survival was observed between groups after 3 years. Changes of the crestal bone level for short and long implants accounted for 0.21 0.63 mm and 0.32 0.70 mm, respectively, without significant intergroup differences. The number of pockets exceeding 4 mm and the percentage of BoP-positive sites did not show any intergroup differences. Crown-to-implant-ratio had no effect on bone loss. Conclusion: At 3 years of loading, short implants of 6 mm showed equally favourable clinical and radiographic outcomes as compared to implants of 10 mm length.

RCI53 Dimensional changes of the alveolar ridge following extraction with and without socket preservation: a clinical and histologic study in humans Y. Mayer, H. Zigdon Giladi, E.E. Machtei Haifa/Israel Aim: To evaluate (clinically, histologically and histo-morphometrically) the use of composite allograft materials [Biphasic calcium sulfate (BCS) with b-TCP and Hydroxyapatite (HA)] in extraction socket sites and compare it to un-disturbed natural healing. Material and Methods: Prospective clinical trial of 36 patients (40 extraction sockets) that were randomly distributed to either test group (allograft and CPF for primary closure) and control group (CPF for primary closure only). Alveolar ridge horizontal dimension was measured in the middle of the socket at three heights: 0, 3 and 6 mm from the crest. Vertical dimension point were measured at baseline surgery and at 4 months re-entry (at which time bone core biopsies were harvested from the center of the edentulous ridge). Histo-morphometric evaluation of the samples was performed using hematoxylin & eosin stains and morphometric software. Results: The changes of horizontal ridge width after 4 months were not statistically significant in both groups. Similarly, at 4 months these dimensions were also similar: 7.2 2.0 vs. 5.8 3.0 (p = 0.31) at crest, 9.0 2.3 vs. 7.5 2.8 (p = 0.14) at 3, 10.2 2.8 vs. 8.4 2.7 (p = 0.25) at 6, for the experimental and control sites respectively. Residual scaffolds occupied 15.99 11.4% of the volume in the grafted sites while the composition of the newly regenerated bone was not statistically different in the 2 groups (47.7 10.6% vs. 52.6 11.6%, p = 0.39). The ratio of the connective tissue in the control group was significant higher (46.7 10.6% vs. 33.3 19.4% for the allograft, p = 0.013). Conclusion: Both techniques resulted in minimal dimensional changes in the alveolar ridge.


RCI54 The use of new porcine-derived collagen matrix for vertical soft tissue augmentation A. Puišys1, T. Linkevicius1, E. Vindasiute1, N. Verina1, M. Schlee2 1

Vilnius/Lithuania, 2Forchheim/Germany

Aim: To evaluate the efficiency of new porcine-derived collagen matrix to augment vertical peri-implant soft tissue thickness during submerged implant placement Material and Methods: Twenty porcine-derived collagen matrix (Mucoderm; Botiss Dental, Berlin, Germany) and 20 bone level implants (Institut Straumann AG, Basel, Switzerland) were placed in submerged approach in 20 patients (7 males and 13 females, mean age 45.2 2.7) with a thin vertical soft tissue thickness of 2 mm or less. After 2 months, healing abutments were connected to implants, and the augmented soft tissue thickness was measured with periodontal probe. The gain in vertical soft tissue volume was calculated. Mann–Whitney U-test was applied and significance was set to 0.05. Results: All 20 xenografts healed successfully. Thin soft tissue before augmentation had an average thickness of 1.65 0.51 mm SD (range, 0.5–2.0 mm, median 1.65 mm), and after soft tissue augmentation with porcine-derived collagen matrix, thickness increased to 3.69 0.54 mm SD (range, 2.8– 4.8 mm, median 4.0 mm) at 2 months after placement. This difference between medians was found to be statistically significant (p < 0.001). Mean increase in soft tissue thickness was 2.01 ‘ 0.85 mm SD (range, 1.0–4.5 mm, median 2.0 mm). Conclusion: It can be concluded that porcine-derived collagen matrix can be successfully used for vertical soft tissue augmentation.

Research session: Periodontal plastic surgery/ regeneration RCI55 Clinical comparison of platelet-rich fibrin membrane with connective tissue graft in combination with a coronally advanced flap in treatment of Miller Class I or II gingival recession: 12-months study M. Sadighi Shamami1, R. Safaralizadeh2, M. Sadighi Shamami1, S. Rikhtegaran1 1

Tabriz/Iran, 2Urumieh/Iran

Aim: The aim of this study was to compare platelet-rich fibrin membrane (PRF) used in combination with coronally advanced flap (CAF) with connective tissue graft (CTG) in CAF procedure for root coverage. Material and Methods: 53 cases with bilateral Miller Class I/ II gingival recession were treated with PRF +CAF (Test group) OR CTG + CAF (Control group). Recession depth (RD), clinical attachment loss (CAL), width of keratinized gingiva (WKG) and percentage of root coverage (PRC) were recorded at baseline, 1, 3, 6 and 12 months posttreatment. Results: RD was 4.25 1.1 mm in PRF group and 3.80 1 mm in CTG group at baseline, 1.39 0.45 and 1.35 0.65 at 3 months and 1.20 0.38, 1.25 0.35 at 6 months and 1.06 0.25 and 1.15 0.45 at 12 months


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respectively. CAL was 5.45 1.2 mm in PRF group and 4.90 1.1 mm in CTG group at baseline, 2.66 0.65 and 2.85 0.45 at 3 months, 2.40 0.28 and 2.45 0.35 at 6 months and 2.26 0.45 and 2.35 0.15 at 12 months respectively. WKT was 1.50 0.46 mm in the CTG group and 1.25 0.89 mm in the PRF group at baseline, 1.66 0.75 and 1.55 0.4 at 3 months, 1.70 0.3 and 1.65 0.35 at 6 months and 1.85 0.5 and 2.0 0.15 at 12 months respectively. PRC in PRF group was 75.47% (40 of 53) and 79.24% in CTG group (42 of 53); the differences between two groups was not statistically significant. Conclusion: PRF +CAF is a predictable treatment for gingival recessions as CTG + CAF.

RCI56 Multicentre multinational trial comparing coronally advanced rotated papillae flaps with connective tissue graft or collagen construct for coverage of multiple adjacent recessions M. Tonetti1, P. Cortellini2, G. Pellegrini1, M. Nieri2, D. Bonaccini2, M. Allegri3, P. Bouchard4, F. Cairo5, G. Conforti6, Y. Fourmousis7, F. Graziani8, A. Guerrero9, J. Halben10, G. Rasperini11, H. Topoll12, H. Wachtel13, B. Wallkamm14, I. Zabalegui15, O. Zuhr13 1

Genoa/Italy, 2Firenze/Italy, 3Verona/Italy, 4Paris/France, Florence/Italy, 6Parma/Italy, 7Athens/Greece, 8Pisa/Italy, 9 Malaga/Spain, 10Hamburg/Germany, 11Milano/Italy, 12Munster/ Germany, 13Munich/Germany, 14Bern/Switzerland, 15Bilbao/Spain 5

Aim: To evaluate the non-inferiority of the adjunct of collagen constructs (CC) or connective tissue graft (CTG) to coronally advanced rotated papillae flaps (CARP) for coverage of multiple adjacent recessions and compare patient reported outcomes. Material and Methods: 187 subjects (92 CC, 31 smokers) with 485 recessions in 14 centres were randomized and followed-up for 6-months. Patients filled daily diaries for 15 days to assess pain, painkillers, OHIP14. CARP were completed before breaking allocation concealment. Collagen constructs (Mucograftâ, Geistlich, Switzerland) or connective tissue grafts were positioned 1 mm below the cement-enamel junction and covered. Multilevel analysis used centre, subject, and tooth as levels and baseline parameters as covariates. Results: Average recession was 2.5 1 mm. The surgery was 16 2 min shorter and lighter (12 4 VAS units, p < 0.001) in CC subjects. OHIP14 scores were significantly lower at day 1, 3 and 7 for CC. CC required analgesics for 1.1 0.4 days less. 6-month root coverage was 2.1 1 for CC and 1.7 1.1 for CTG. 95% CI of the difference in REC coverage was 0.25– 0.63 mm and larger than the clinical margin of 0.25 mm. Odds of complete root coverage were significantly higher for CTG (OR = 4, 95% CI 1.8–8.8). Conclusion: The null hypothesis that the addition of CC to CARP was inferior to CGT could not be rejected. CC patients reported less pain and interference with quality of life in the 1st post-op week. This investigator-initiated study was supported by an unrestricted grant from Geistlich. Authors were fully independent at all stages of this research.


RCI57 Conventional one-stage versus two-stage aesthetic crown lengthening for restorative purposes. A 12month randomized controlled clinical trial O. González-Martın, G. Carbajo, M. Sanz Madrid/Spain Aim: To assess the efficacy of the two stage surgical crown lengthening protocol for aesthetic restorative purposes and to compare the outcome and wound healing dynamics with the one-stage surgical crown lengthening procedure. In particular, we evaluate as primary outcome, the positional changes of the free gingival margin and the stability of the established crown length over 12-month period. Material and Methods: To date, a randomized clinical trial was carried out with 12 patients. The individuals were randomly allocated to the conventional 1 stage approach (C1S) and test 2 stage approach (T2S). PVS impressions, photos and periodontal standard measurements were taken at baseline, before gingival stage (for T2S), 6 and 12 months. Stability of the gingival margin was evaluated by linear and quantitative 3D analysis. Results: The preliminary results of the first 12 patients at 6 months reveal a displacement of the gingival margin of 0.92 mm apically following the conventional procedure and a displacement of 1.05 mm (0.8–1.3 mm) following the twostages procedure. For C1S, crown length increases (though not statistically significant) from Baseline to 2 weeks and continues to increase to a lesser extent at 6 months. For T2S, the length of the crown does not vary between Baseline and 2 weeks. However, this length tends to increase significantly between 2 weeks and 4 months, and continues to increase up to 6 months. Conclusion: Within the limitation of the study, no significant difference was found regarding length of the crown and stability of the gingival margin when comparing control group and test group.

RCI58 Predictors of gingival recession following surgical treatment of periodontal intraosseous defects with a simplified procedure: an exploratory analysis A. Simonelli1, R. Farina1, L. Minenna1, G.P. Schincaglia2, G. Rasperini3, L. Trombelli1 Ferrara/Italy, 2Farmington/United States of America, 3Milano/Italy

1

Aim: to identify potential predictors of the 6-month change in buccal gingival recession (bREC) following treatment of periodontal intraosseous defects according to the Single Flap Approach (SFA) (Trombelli et al., 2007, 2009). Material and Methods: Data were retrospectively derived from the record charts of patients seeking care at 3 clinical centers. Patients contributing 1 isolated intraosseous defect undergone surgical treatment with a buccal SFA either per se or in association with graft materials, membrane devices and/or bioactive agents, were included for analysis. Patients were grouped according to the change in bREC occurred at 6 months following surgery (HIGH group: bREC increase >1.0 mm; LOW group: bREC increase = 01.0 mm; STABLE group: no bREC change or bREC decrease). Groups were compared for

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patient-related factors (age, gender, smoking status, gingival phenotype), site-related characteristics (dental arch, tooth type, defect morphology, probing parameters) and reconstructive strategy. Results: STABLE, LOW and HIGH groups comprised 29 (39.2%), 33 (44.6%), and 12 (16.2%) patients, respectively. When compared to the STABLE group, the HIGH group showed a significantly greater pre-surgery buccal dehiscence (p = 0.004) and higher pre-surgery interproximal severity of bone loss (p = 0.032), clinical attachment level (p = 0.026), and probing pocket depth (p = 0.039). Conclusion: The severity of interproximal bone loss and the depth of the buccal dehiscence are candidate predictors for bREC increase following treatment of periodontal intraosseous defects with the Single Flap Approach.

RCI59 Periodontal regeneration with non-resorbable barriers versus flap surgery in human infrabony defects. A 17-years long-term controlled clinical trial P. Cortellini1, J. Buti2, F. Cairo1, D. Bonaccini1, F. Graziani3, M. Tonetti4 1 Firenze/Italy, 2Manchester/United Kingdom, 3Pisa/Italy, 4Genoa/ Italy

Aim: To compare the long-term stability of 3 different treatment modalities in deep intrabony defects. Material and Methods: A group received the modified papilla preservation technique with titanium reinforced polytetrafluoroethylene (e-PTFE) membranes (MPPT-Tit, N = 15); a second group a flap with e-PTFE barriers (Flap-ePTFE, N = 15); the third group an access flap alone (Flap, N = 15). Patients were maintained by monthly supportive periodontal care (SPC) for 1 year, then enrolled into a 3-month SPC. Adjunctive periodontal therapy was delivered to sites showing recurrences. Teeth not responding to therapy were extracted during the SPC period.


RCI60 A histopathological investigation on the effects of electrical stimulation on periodontal regeneration in experimental bony defects in dogs M.D. Kaynak Ankara/Turkey Aim: One end point of periodontal therapy is to regenerate the structure lost due to periodontal disease. Several procedural advances may support regenerations however the regeneration of alveolar bone does not always occur. In this respect, the present study was designed to examine histopathologically whether the application of an electrical field could demonstrate enhanced alveolar and cementum regeneration and modify tissue factors. Material and Methods: Seven beagle dogs were used for this experiment. Mandibular left and right sides served as control and experimental sides. Four-walled infrabony defects were created bilaterally between the third and fourth premolars. The experimental side was treated with a capacitively coupled electrical field (sinusoidal wave, 60 kHz, 5 Volt, peak to peak) applied for 14 h a day. The measurements indicating new bone fill, thickness of the cementum, length of junctional epithelium were performed on the microphotographs. Semi-quantitative subjective method was realized to assess the histopathological parameters involving inflammatory cell infiltration; cellular activity of periodontal ligament; number and morphology of osteoclasts; resorption lacunae and osteoblastic activity. Results: The most characteristic finding was the quantity of new bone fill and the mean value of cementum thickness which demonstrated significantly higher values in the experimental side (p < 0.01). The histopathologic evaluations demonstrated statistically significant differences in all defined histopathologic parameters except for osteoclasts morphologies (p > 0.05) in favor of the stimulated mandibles. Conclusion: Electromotive forces are the current promise to achieve a new dimension for periodontal therapy. Future investigations should be carried out with the appropriate dose-respond parameters and local characteristics of the stimulated area.

Results: Four drop-outs occurred (MPPT-Tit 1, Flap-ePTFE 2, and Flap 1). The remaining 41 patients complied with the SPC for 17 years. Two teeth were lost from the Flap group, 11 and 15 years after surgery. A total of 4 recurrences in 3 patients were observed in the MPPT-Tit group, 5 in 4 patients in the FlapePTFE, and 12 in 8 patients in the Flap group. Differences in clinical attachment level (CAL) between 1 and 17 years were 0.3 0.2 mm (p = 0.2178) in the MPPT-Tit; 0.5 0.1 mm (p = 0.0075) in the Flap-ePTFE; 1.1 0.3 mm (p = 0.0016) in the Flap group. A regression analysis showed a tendency toward a significant correlation between CAL loss and the Flap approach (p = 0.0658), indicating that sites treated with flap alone tended to lose more attachment over time compared to MPPT-Tit ( 0.7 0.4 mm).

1

Conclusion: Deep intrabony defects treated with regenerative procedures are substantially more stable over time and show less recurrences and loss of teeth than defects treated with flap alone.

Aim: To analyse the implant stability quotient (ISQ) values achieved on different bone densities modifying the drilling protocol with 1-year follow-up.

Clinical innovations: implants 2 RCI61 Comparative prospective clinical trial about the implants stability quotient on different bone qualities. 1-year follow-up J.M.D. Muñoz1, D. Torres-Lagares1, R.M. Dıaz-Sanchez1, A. Meyer2, P. Zeman2, G. Machuca-Portillo1 Seville/Spain, 2Grenchen/Switzerland

Material and Methods: A prospective clinical trial was carried out on 27 patients in which 67 hydrophilic titanium implants were inserted after fulfilling the selection criteria. High-resolution Cone beam computed tomography (CBCT) and visual assessment after pilot drilling were used to classify bone quality. Two drilling protocols were established based on the bone quality (I and II or III and IV). ISQ was measured immediately


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after implant surgery, at uncovering stage surgery, and 6 months and 1 year after in order to assess changes during titanium implant osseointegration. Results: ISQ measurement immediately after surgery had high correlation (R2 = 0.99) with bone quality classification. No statistically significant differences were found between ISQ and the different bone density (I/II and III/IV). The more dense mandibular bone was reflected by the consistently higher ISQ. A trend towards increasing ISQ was found over the 1-year trial period. NO statistically significant differences were found after 1-year follow-up. Conclusion: The implant stability in different bone quality was achieved by adapting the drilling protocol. The ISQ measurement was a reliable predictor of implants stability.

RCI62 Peri-implant and periodontal microbiomes in aggressive periodontitis patients V. Sousa, J. Dopico, L. Nibali, N. Mardas, D. Spratt, N. Donos London/United Kingdom Aim: To investigate the diversity of the bacterial metagenome as well as to describe not previously identified taxa in periodontal and peri-implant biofilms from aggressive periodontitis patients (AgP). Material and Methods: Twenty-four plaque samples were collected from 18 patients previously diagnosed and treated for AgP. The samples were taken from (number of patients): 6 residual pockets ≥6 mm –AgP (n = 6), 6 healthy sites

Abstracts of the ILTS 20(th) Annual International Congress, June 3-7, 2014, London, United Kingdom.

Abstracts of the AAGBI GAT Annual Scientific Meeting, 11-13 June 2014, Newcastle, UK.

Abstracts of the 4th UK Paediatric Neuropsychology Symposium: Atypical Developmental Pathways, 19-23 May 2014, London, UK.

Abstracts of the Diabetes UK Professional Conference 2015, 11-13 March, 2015, London, England .

Heberden Society clinical meeting, June 1978. Abstracts.

Alfred William Frankland. London, UK.

London Trauma Conference 2015 : London, UK, 8-11 December 2015.

Abstracts of the London Trauma Conference 2013, December 10-13, 2013, London, United Kingdom.

Abstracts of the AAGBI WSM London, 15-17 January 2014.

Abstracts : BAFM Winter Meeting 2006, Leicester, UK.

Two Linked Enteroinvasive Escherichia coli Outbreaks, Nottingham, UK, June 2014.

Evaluating ear cartilage piercing practices in London, UK.

Abstracts of the Annual European Congress of Rheumatology EULAR. June 12-15, 2013. Madrid, Spain.

Abstracts of the XXIV European Congress of Perinatal Medicine, June 4-7, 2014, Florence, Italy.

Proceedings of the scientific meetings of The Physiological Society. June 1991 thru November 1991. Abstracts.

Abstracts of the 1st Congress of the European Academy of Neurology, Berlin, Germany, June 2015.

XXV Nordic-Baltic Congress of Cardiology. Tallinn, Estonia, June 4-6, 2015: Abstracts.

Abstracts of the British Society of Gastroenterology Annual General Meeting. June 16-19, 2014.

ISOO Symposium, June 26-28, 2014, Miami, Florida.

Abstracts of the 2014 AWHONN Annual Convention, June 14-18, 2014, Orlando, Florida.

Sixth Scientific Meeting of the British Oncological Association. 30th June-2nd July 1991, Bath. Abstracts.

Abstracts of the Joint Congress of European Neurology, 31 May-3 June, 2014, Istanbul, Turkey.

Abstracts from the Cardiovascular Research: Bench to Bedside and Back Again. A 40th Anniversary Celebration of the BSCR. September 9-10, 2013, London, UK.

Abstracts of the 11th European Congress on Epileptology, 29 June - 3 July, 2014, Stockholm, Sweden.