Journal of Periodontology; Copyright 2015
DOI: 10.1902/jop.2015.140646
Platelet Rich Fibrin with 1% Metformin for the Treatment of Intrabony Defects in Chronic Periodontitis: A Randomized Controlled Clinical Trial Dr. A R Pradeep MDS*, Dr. Kanika Nagpal BDS (MDS)*, Dr. Shruti Karvekar BDS (MDS)*, Dr. Kaushik Patnaik BDS (MDS)*, Dr. Savitha B. Naik MDS†, Dr. C N Guruprasad MDS* *Department of Periodontics, Government Dental College and Research Institute Bangalore560002, Karnataka, INDIA. †
Department of Conservative Dentistry and Endodontics Government Dental College and Research Institute Bangalore-560002, Karnataka, INDIA.
Background: Platelet-rich fibrin (PRF) is a second-generation platelet concentrate which releases various growth factors that promote tissue regeneration. Metformin (MF), a member of biguanide group has been shown to facilitate osteoblast differentiation and thus may exhibit a favourable effect on alveolar bone . The current study was designed to evaluate the efficacy of PRF, 1% MF gel and PRF+1%MF gel, with open flap debridement (OFD), in the treatment of intrabony defects in chronic periodontitis (CP) patients. Methods: One hundred and twenty patients with single defects were categorized into four treatment groups: OFD alone, OFD with PRF, OFD with 1% MF and OFD + PRF+1% MF. Clinical parameters like site specific plaque index (PI), modified sulcus bleeding index (mSBI), probing depth (PD), relative attachment level (RAL) and gingival marginal level (GML) were recorded at baseline, before surgery and 9 months postoperatively. Percentage radiographic intra-bony defect depth reduction was evaluated using computer-aided software at baseline and 9 months. Results: PRF, 1%MF and PRF+1% MF groups showed significant PD reduction and RAL gain than OFD group. Mean PD reduction and mean RAL gain was found to be greater in PRF+1% MF group as compared to PRF alone or MF alone at 9 months. Furthermore, PRF+1% MF group sites showed a significantly greater percentage radiographic defect depth reduction (52.65% ± 0.031%) as compared to MF alone (48.69± 0.026 % ) , PRF alone (48 % ± 0.029%) and OFD (9.14±0.04%) at 9 months. Conclusion: PRF+1% MF group showed greater improvements in clinical parameters with greater percentage radiographic defect depth reduction as compared to MF alone, PRF alone or OFD alone in treatment of intrabony defects in CP patients.
KEYWORDS: Periodontal Surgery, Periodontal Regeneration, Growth factors, Clinical trials.
Periodontal disease is marked by prolonged inflammation of the periodontal tissues resulting in connective tissue attachment loss and alveolar bone resorption.1 Regeneration of the lost periodontal tissues is the fundamental objective of periodontal therapy.2 While reports of successful periodontal regeneration can be found throughout the periodontal literature, there can be little doubt that traditional surgical or non surgical approaches to periodontitis do not generally lead to regeneration.3 Currently a novel approach to attain periodontal regeneration is the use of platelet concentrates that release polypeptide growth factors (PGFs) that have the ability to regulate cell proliferation, chemotaxis, and differentiation, which may directly contribute to formation of new tissues.4 Platelet rich fibrin (PRF), a second generation platelet concentrate was first developed by Choukroun5 and consists of a slowly polymerized fibrin network containing components like cytokines, glycanic chains and structural glycoproteins, which help in healing.6 These cytokines may be liberated during the remodelling of the fibrin matrix.5 Further healing is
1
Journal of Periodontology; Copyright 2015
DOI: 10.1902/jop.2015.140646
aided by its beneficial physical structure containing trimolecular or equilateral junctions, formed due to its slow polymerisation method of preparation, which aids in the entrapment of cytokines.5,7,8 In a study, PRF with open flap debridement(OFD) has shown to give better results than open flap debridement alone, in the treatment of intrabony defects in relation to the probing depth (PD) reduction, RAL gain and bone fill.2 There has always been a close association between chronic periodontitis (CP) and diabetes.9 Metformin HCl (1,1-dimethylbiguanide HCl) (MF), a second generation biguanide has been used very commonly for type II diabetes mellitus treatment.10 In a study, MF has shown to encourage the activity of alkaline phosphatase in MC3T3E1 type of osteoblasts and helps in the collagen fabrication (type1), in both UMR106 and MC3T3E1 type of cells, thus facilitating the differentiation of osteoblasts and the formation of bone.11,12. Therefore, by facilitating osteoblast differentiation, MF may exhibit a favourable effect on alveolar bone, in periodontitis.12 However, it had no effect on osteoclast and adipocyte formation.12 Further, different concentrations of MF (0.5%, 1% and 1.5%) used locally in the treatment of CP proved 1% concentration to be most effective, both clinically and radiographically.13 Recently, our studies indicate that SRP with 1% MF was more effective than SRP with placebo, in decreasing the PD and mean sulcular bleeding index and showing a gain in clinical attachment level (CAL) in patients with CP who were smokers.14 Till date no study has evaluated the effect of PRF, 1% MF gel and PRF+ 1% MF gel, with OFD in the treatment of intrabony defects in CP patients. Thus. the aim of our study is to investigate the effectiveness (both clinical and radiographic) of OFD, OFD+ autologous PRF, OFD + 1%MF gel and OFD + PRF +1% MF gel in the treatment of 2/3 wall intrabony defects (IBDs).
MATERIALS AND METHODS This was a randomized, single-centre, longitudinal, triple masked (investigators, individuals and statistician), parallel arm design study. This study was conducted for a total of 9 months, in which recordings were done at baseline and at 9 months. A total of one hundred and thirty six patients (68 males, 68 females, mean age 41 yrs) were recruited from the Department of Periodontics, Government Dental College and Research Institute, Bangalore, India. The study was conducted from november 2013 to july 2014. The research protocol was initially submitted to the Institutional Ethical Committee and Review Board of the Government Dental College and Research Institute. After ethical approval, all participants were verbally informed, and written informed consent was collected for participation in the study. The study protocol was approved and registered under clinicaltrials.gov with identifier number NCT02283554. Inclusion Criteria The patients were classified as having moderate to severe CP based on the 1999 consensus classification of periodontal diseases.15 The inclusion criteria included the presence of IBD ≥3 mm deep (distance between alveolar crest and base of the defect on an intraoral periapical radiograph [IOPA] ) along with
2
Journal of Periodontology; Copyright 2015
DOI: 10.1902/jop.2015.140646
an interproximal probing depth (PD) ≥5 mm after phase I therapy (scaling and root planing [SRP] ) in asymptomatic maxillary/ mandibular molar teeth. Exclusion Criteria Exclusion criteria were: 1) Aggressive Periodontitis patients; 2) Patients with systemic conditions known to affect the periodontal status; 3) medications known to affect the outcomes of periodontal therapy; 4) Hematological disorders and insufficient platelet count ( 1.5) after re-evaluation of Phase I therapy were also excluded from the study. In addition, teeth with furcation defects, non vital teeth, carious teeth warranting restorations and mobility of at least grade II were also excluded. Pre-surgical Therapy: Before the surgery, each patient was given careful instructions on proper oral hygiene measures. A full mouth supragingival and subgingival SRP procedure was performed under local anaesthesia using ultrasonic and hand instrumentation. Six to 8 weeks after phase I therapy, periodontal evaluation was performed to confirm the desired sites for the study. One site (with the deepest interproximal PD ( ≥5 mm) after phase 1 therapy ) was selected from each patient. These patients were divided randomly (computer generated tables) into four groups .Group 1 consists of 34 sites treated with Open flap debridement i.e. conventional flap surgery, group 2 consists of 34 sites treated with OFD with autologous PRF, group 3 included 34 sites treated with OFD with 1%MF gel and group 4 had 34 sites treated with OFD, autologous PRF and 1% MF gel. One operator (KN) performed all the surgeries, whereas another operator (ARP) performed all the clinical and radiographic measurements without knowledge of the groups. Patients were masked for allocation to particular group and treatment. Intra-examiner Calibration: Intra-examiner calibration was achieved by examination of 25 sites twice, 24 h apart before beginning the study. Calibration was accepted if measurements at baseline and 24 h were similar to 1 mm at the 95% level. Clinical and Radiographic Measurements: The clinical parameters recorded before surgical procedures included site-specific PI, modified sulcus bleeding index17 (mSBI), PD from the gingival margin, relative attachment level (RAL), and gingival marginal level (GML) from the apical level of customized acrylic stents with grooves to ensure a reproducible placement of the periodontal probe§. All IBDs were assessed at baseline and at 9 months after the surgery. For the measurement of the bone defect, the distance from the crest of the alveolar bone to the base of the defect was considered. Individually customized bite blocks and the parallel angle technique were used to obtain standardized radiographs. For assessment, radiographs were scanned with a scanner‖ of 6,400 dots per inch by an evaluator (ARP) who was masked to the surgical procedure performed in the participants. The radiographic IBD depth was measured using a computer aided software programme¶ as used formerly.18,19
3
Journal of Periodontology; Copyright 2015
DOI: 10.1902/jop.2015.140646
PRF Preparation: The PRF was prepared according to protocol developed by Choukroun et al.5 and as followed in our earlier studies.18,19 Before the surgery, intravenous blood was collected by venipuncturing of the antecubital vein in three 10-mL sterile tubes without anticoagulant and immediately centrifuged in a centrifugation machine# at 3,000 revolutions (approx 400 g) per minute for a period of 10 minutes. Centrifugation immediately after blood collection allows the composition of a structured fibrin clot in the middle of the tube, between the red blood corpuscles at the bottom and acellular plasma (platelet-poor plasma [PPP] ) at the top. Separation of PRF from red corpuscles base was done (preserving a small red blood cell [RBC] layer) using sterile tweezers and scissors just after removal of PPP after which, it was transferred onto a sterile gauze compress. A stable fibrin membrane was obtained by squeezing serum out of the PRF clot. Formulation of 1% MF Gel MF gel was prepared as described by the authors in a previous study.13 Briefly, all the required ingredients of the formulation were weighed accurately. A dispersion of dry gellan gum powder and distilled water was mixed with a magnetic stirrer* at 95°C for a period of twenty minutes to promote the formation of hydrous gellan gum. To this solution, the required amount of mannitol was included, with the temperature maintained at >80°C. After this, MF (weighed amount) was added, followed by the addition of citric acid, sucralose and preservatives like propylparaben and methylparaben. A continuous stirring was done during all this procedure. To this mixture, the necessary quantity of sodium citrate (dissolved in 10 ml distilled water) was added. This mixture formed into a gel when allowed to cool at room temperature. Thus, the MF in situ gel was prepared with a concentration ~1%. Surgical Procedure: Pre-surgical mouthrinse was carried out with 0.12% chlorhexidine digluconate rinse, and, Povidone iodine solution was used to perform extraoral antisepsis. After administration of local anesthesia, intracrevicular incisions were made both buccally and lingually. This was followed by the reflection of mucoperiosteal flaps. Care was taken to preserve the maximum amount of inter-proximal soft tissue. Thorough defect debridement and root planing were performed using ultrasonic instrumentation⃰ * and area-specific currets††. No osseous recontouring was performed. One hundred and twenty six patients were finally considered as ten of them were excluded during surgery (because they did not present with 3 walled IBD’s.) In group 1 (OFD group, 32 patients), only open flap debridement was done, without addition of any regenerative material in to the bone defect. However, in group 2 (OFD plus PRF group, 32 patients), PRF of the required size was filled into the IBD after OFD. In group 3 (OFD plus MF gel group., 31 patients), 10 µl of 1% MF gel was inserted into the IBD after OFD. Whereas, in group 4 ( OFD plus 1% MF plus PRF group, 31 patients), equal amounts of PRF and MF gel were mixed and then were inserted into the IBD after OFD. Compressed PRF membranes (2 PRF’s were used to make 1 PRF membrane) were adapted over the defects (in group 2, 3 and 4) in order to protect the PRF, 1%MF and PRF+1% MF in the defect space. The mucoperiosteal flaps were repositioned and secured in place using 3-0 nonabsorbable silk surgical suture‡ ‡. The interrupted or sling sutures were placed. The surgical area was protected and covered with periodontal dressing§§. Patients were given necessary post-operative instructions and oral hygiene instructions were reinforced.
4
Journal of Periodontology; Copyright 2015
DOI: 10.1902/jop.2015.140646
Postoperative Care: Antibiotics and analgesics (500 mg amoxicillin, TDS for 7 days; 500 mg metronidazole, TDS for 7 days and 800 mg ibuprofen, TDS) were prescribed, along with chlorhexidine digluconate rinses (0.12%) twice daily for 2 weeks. Periodontal dressing and sutures were removed 2 weeks postoperatively. Surgical wounds were gently cleansed with 0.12% chlorhexidine digluconate, and participants were instructed for gentle brushing with a soft toothbrush. Each patient was reinstructed for proper oral hygiene measures at 8 weeks postoperatively and examined weekly for 1 month post-surgery and again at 3 and 9 months.. No subgingival instrumentation was attempted at any of these appointments. Post-Surgical Measurements: Soft and hard tissue evaluation was performed 9 months post-surgery. Soft tissue measurements were repeated with previously used acrylic stents. For hard tissue reevaluation, a second IOPA of the same study site was performed, and IBD measurement was reassessed at 9 months. Primary and Secondary Outcome Measures: The primary outcome of the study was radiographic defect depth reduction from baseline to 9 months. The secondary outcomes included changes in PD, RAL, GML, mSBI, and PI in the 9 months duration. Statistical Analysis: The data were analyzed using statistical software‖‖. Power calculations were performed before the study was initiated. To achieve 90% power and detect mean differences of the clinical parameters between groups, 30 sites per group were required. The results were averaged (mean standard deviation) for each clinical and radiographic parameter at baseline and 9 months. mSBI and PI were expressed as absolute and relative counts and comparison was performed using Chi-square test. Normality assumption of the data was tested using the Shapiro-Wilk test. The difference between each pair of measurements was then calculated (baseline to 9 months). Paired t test was applied to assess the statistical significance between time points within each group for clinical and radiographic parameters. Analysis of variance and post hoc Scheffe´ test were applied to assess the statistical significance between time points among the groups for clinical and radiographic parameters. The mean intra-examiner standard deviation of differences in repeated PD measurements and RAL measurements was obtained using single passes of measurements with a periodontal probe (correlation coefficients between duplicate measurements; r = 0.95).
RESULTS: One hundred and twenty patients (120 sites) of 126 participants completed the study (Fig. 1), since, six of them failed to followup. All treated cases showed uneventful wound healing and the drug was well tolerated by all the patients. Table 1 shows the basic demographic characteristics of the study population. There were no statistically significant differences in the mean age and gender of the patients in all the four groups. Supplementary tables 1 and 2 in the online Journal of Periodontology show the characteristics of the defects in all the 4 groups.
5
Journal of Periodontology; Copyright 2015
DOI: 10.1902/jop.2015.140646
A reduction in both PI and mSBI was observed in all four groups at 9 months postoperatively, however, the reduction was not statistically significant among the four groups. (Table 2). This indicates that an equivalent oral hygiene was maintained by patients of all the groups all through the study. Mean ± SD values for clinical and radiologic parameters at baseline and 9 months are reported in Table 3. There was no statistically significant difference in clinical (PD, RAL, GML) and radiological (IBD) parameters when the four groups were compared at baseline. However, a statistically significant difference in these parameters was noted when these groups were compared at 9 months. Table 4 shows the mean changes in the clinical and radiologic parameters (from baseline to 9 months). Also see supplementary Figures 1 and 2 in the online Journal of Periodontology. PRF, 1%MF and PRF+1% MF sites presented with a significantly greater PD reduction than control sites at 9 months postoperatively (P ≤0.05). The reduction in PD was greater in PRF+ 1% MF group (4.90±0.31 mm) when compared to MF (3.93 ± 0.25mm), PRF (4.00±0.18 mm) and OFD group (3.00±0.18 mm). (Table 4). RAL gain was also greater in the PRF, MF and PRF+1% MF sites compared to control sites, the difference being statistically significant (p
DOI: 10.1902/jop.2015.140646
Platelet Rich Fibrin with 1% Metformin for the Treatment of Intrabony Defects in Chronic Periodontitis: A Randomized Controlled Clinical Trial Dr. A R Pradeep MDS*, Dr. Kanika Nagpal BDS (MDS)*, Dr. Shruti Karvekar BDS (MDS)*, Dr. Kaushik Patnaik BDS (MDS)*, Dr. Savitha B. Naik MDS†, Dr. C N Guruprasad MDS* *Department of Periodontics, Government Dental College and Research Institute Bangalore560002, Karnataka, INDIA. †
Department of Conservative Dentistry and Endodontics Government Dental College and Research Institute Bangalore-560002, Karnataka, INDIA.
Background: Platelet-rich fibrin (PRF) is a second-generation platelet concentrate which releases various growth factors that promote tissue regeneration. Metformin (MF), a member of biguanide group has been shown to facilitate osteoblast differentiation and thus may exhibit a favourable effect on alveolar bone . The current study was designed to evaluate the efficacy of PRF, 1% MF gel and PRF+1%MF gel, with open flap debridement (OFD), in the treatment of intrabony defects in chronic periodontitis (CP) patients. Methods: One hundred and twenty patients with single defects were categorized into four treatment groups: OFD alone, OFD with PRF, OFD with 1% MF and OFD + PRF+1% MF. Clinical parameters like site specific plaque index (PI), modified sulcus bleeding index (mSBI), probing depth (PD), relative attachment level (RAL) and gingival marginal level (GML) were recorded at baseline, before surgery and 9 months postoperatively. Percentage radiographic intra-bony defect depth reduction was evaluated using computer-aided software at baseline and 9 months. Results: PRF, 1%MF and PRF+1% MF groups showed significant PD reduction and RAL gain than OFD group. Mean PD reduction and mean RAL gain was found to be greater in PRF+1% MF group as compared to PRF alone or MF alone at 9 months. Furthermore, PRF+1% MF group sites showed a significantly greater percentage radiographic defect depth reduction (52.65% ± 0.031%) as compared to MF alone (48.69± 0.026 % ) , PRF alone (48 % ± 0.029%) and OFD (9.14±0.04%) at 9 months. Conclusion: PRF+1% MF group showed greater improvements in clinical parameters with greater percentage radiographic defect depth reduction as compared to MF alone, PRF alone or OFD alone in treatment of intrabony defects in CP patients.
KEYWORDS: Periodontal Surgery, Periodontal Regeneration, Growth factors, Clinical trials.
Periodontal disease is marked by prolonged inflammation of the periodontal tissues resulting in connective tissue attachment loss and alveolar bone resorption.1 Regeneration of the lost periodontal tissues is the fundamental objective of periodontal therapy.2 While reports of successful periodontal regeneration can be found throughout the periodontal literature, there can be little doubt that traditional surgical or non surgical approaches to periodontitis do not generally lead to regeneration.3 Currently a novel approach to attain periodontal regeneration is the use of platelet concentrates that release polypeptide growth factors (PGFs) that have the ability to regulate cell proliferation, chemotaxis, and differentiation, which may directly contribute to formation of new tissues.4 Platelet rich fibrin (PRF), a second generation platelet concentrate was first developed by Choukroun5 and consists of a slowly polymerized fibrin network containing components like cytokines, glycanic chains and structural glycoproteins, which help in healing.6 These cytokines may be liberated during the remodelling of the fibrin matrix.5 Further healing is
1
Journal of Periodontology; Copyright 2015
DOI: 10.1902/jop.2015.140646
aided by its beneficial physical structure containing trimolecular or equilateral junctions, formed due to its slow polymerisation method of preparation, which aids in the entrapment of cytokines.5,7,8 In a study, PRF with open flap debridement(OFD) has shown to give better results than open flap debridement alone, in the treatment of intrabony defects in relation to the probing depth (PD) reduction, RAL gain and bone fill.2 There has always been a close association between chronic periodontitis (CP) and diabetes.9 Metformin HCl (1,1-dimethylbiguanide HCl) (MF), a second generation biguanide has been used very commonly for type II diabetes mellitus treatment.10 In a study, MF has shown to encourage the activity of alkaline phosphatase in MC3T3E1 type of osteoblasts and helps in the collagen fabrication (type1), in both UMR106 and MC3T3E1 type of cells, thus facilitating the differentiation of osteoblasts and the formation of bone.11,12. Therefore, by facilitating osteoblast differentiation, MF may exhibit a favourable effect on alveolar bone, in periodontitis.12 However, it had no effect on osteoclast and adipocyte formation.12 Further, different concentrations of MF (0.5%, 1% and 1.5%) used locally in the treatment of CP proved 1% concentration to be most effective, both clinically and radiographically.13 Recently, our studies indicate that SRP with 1% MF was more effective than SRP with placebo, in decreasing the PD and mean sulcular bleeding index and showing a gain in clinical attachment level (CAL) in patients with CP who were smokers.14 Till date no study has evaluated the effect of PRF, 1% MF gel and PRF+ 1% MF gel, with OFD in the treatment of intrabony defects in CP patients. Thus. the aim of our study is to investigate the effectiveness (both clinical and radiographic) of OFD, OFD+ autologous PRF, OFD + 1%MF gel and OFD + PRF +1% MF gel in the treatment of 2/3 wall intrabony defects (IBDs).
MATERIALS AND METHODS This was a randomized, single-centre, longitudinal, triple masked (investigators, individuals and statistician), parallel arm design study. This study was conducted for a total of 9 months, in which recordings were done at baseline and at 9 months. A total of one hundred and thirty six patients (68 males, 68 females, mean age 41 yrs) were recruited from the Department of Periodontics, Government Dental College and Research Institute, Bangalore, India. The study was conducted from november 2013 to july 2014. The research protocol was initially submitted to the Institutional Ethical Committee and Review Board of the Government Dental College and Research Institute. After ethical approval, all participants were verbally informed, and written informed consent was collected for participation in the study. The study protocol was approved and registered under clinicaltrials.gov with identifier number NCT02283554. Inclusion Criteria The patients were classified as having moderate to severe CP based on the 1999 consensus classification of periodontal diseases.15 The inclusion criteria included the presence of IBD ≥3 mm deep (distance between alveolar crest and base of the defect on an intraoral periapical radiograph [IOPA] ) along with
2
Journal of Periodontology; Copyright 2015
DOI: 10.1902/jop.2015.140646
an interproximal probing depth (PD) ≥5 mm after phase I therapy (scaling and root planing [SRP] ) in asymptomatic maxillary/ mandibular molar teeth. Exclusion Criteria Exclusion criteria were: 1) Aggressive Periodontitis patients; 2) Patients with systemic conditions known to affect the periodontal status; 3) medications known to affect the outcomes of periodontal therapy; 4) Hematological disorders and insufficient platelet count ( 1.5) after re-evaluation of Phase I therapy were also excluded from the study. In addition, teeth with furcation defects, non vital teeth, carious teeth warranting restorations and mobility of at least grade II were also excluded. Pre-surgical Therapy: Before the surgery, each patient was given careful instructions on proper oral hygiene measures. A full mouth supragingival and subgingival SRP procedure was performed under local anaesthesia using ultrasonic and hand instrumentation. Six to 8 weeks after phase I therapy, periodontal evaluation was performed to confirm the desired sites for the study. One site (with the deepest interproximal PD ( ≥5 mm) after phase 1 therapy ) was selected from each patient. These patients were divided randomly (computer generated tables) into four groups .Group 1 consists of 34 sites treated with Open flap debridement i.e. conventional flap surgery, group 2 consists of 34 sites treated with OFD with autologous PRF, group 3 included 34 sites treated with OFD with 1%MF gel and group 4 had 34 sites treated with OFD, autologous PRF and 1% MF gel. One operator (KN) performed all the surgeries, whereas another operator (ARP) performed all the clinical and radiographic measurements without knowledge of the groups. Patients were masked for allocation to particular group and treatment. Intra-examiner Calibration: Intra-examiner calibration was achieved by examination of 25 sites twice, 24 h apart before beginning the study. Calibration was accepted if measurements at baseline and 24 h were similar to 1 mm at the 95% level. Clinical and Radiographic Measurements: The clinical parameters recorded before surgical procedures included site-specific PI, modified sulcus bleeding index17 (mSBI), PD from the gingival margin, relative attachment level (RAL), and gingival marginal level (GML) from the apical level of customized acrylic stents with grooves to ensure a reproducible placement of the periodontal probe§. All IBDs were assessed at baseline and at 9 months after the surgery. For the measurement of the bone defect, the distance from the crest of the alveolar bone to the base of the defect was considered. Individually customized bite blocks and the parallel angle technique were used to obtain standardized radiographs. For assessment, radiographs were scanned with a scanner‖ of 6,400 dots per inch by an evaluator (ARP) who was masked to the surgical procedure performed in the participants. The radiographic IBD depth was measured using a computer aided software programme¶ as used formerly.18,19
3
Journal of Periodontology; Copyright 2015
DOI: 10.1902/jop.2015.140646
PRF Preparation: The PRF was prepared according to protocol developed by Choukroun et al.5 and as followed in our earlier studies.18,19 Before the surgery, intravenous blood was collected by venipuncturing of the antecubital vein in three 10-mL sterile tubes without anticoagulant and immediately centrifuged in a centrifugation machine# at 3,000 revolutions (approx 400 g) per minute for a period of 10 minutes. Centrifugation immediately after blood collection allows the composition of a structured fibrin clot in the middle of the tube, between the red blood corpuscles at the bottom and acellular plasma (platelet-poor plasma [PPP] ) at the top. Separation of PRF from red corpuscles base was done (preserving a small red blood cell [RBC] layer) using sterile tweezers and scissors just after removal of PPP after which, it was transferred onto a sterile gauze compress. A stable fibrin membrane was obtained by squeezing serum out of the PRF clot. Formulation of 1% MF Gel MF gel was prepared as described by the authors in a previous study.13 Briefly, all the required ingredients of the formulation were weighed accurately. A dispersion of dry gellan gum powder and distilled water was mixed with a magnetic stirrer* at 95°C for a period of twenty minutes to promote the formation of hydrous gellan gum. To this solution, the required amount of mannitol was included, with the temperature maintained at >80°C. After this, MF (weighed amount) was added, followed by the addition of citric acid, sucralose and preservatives like propylparaben and methylparaben. A continuous stirring was done during all this procedure. To this mixture, the necessary quantity of sodium citrate (dissolved in 10 ml distilled water) was added. This mixture formed into a gel when allowed to cool at room temperature. Thus, the MF in situ gel was prepared with a concentration ~1%. Surgical Procedure: Pre-surgical mouthrinse was carried out with 0.12% chlorhexidine digluconate rinse, and, Povidone iodine solution was used to perform extraoral antisepsis. After administration of local anesthesia, intracrevicular incisions were made both buccally and lingually. This was followed by the reflection of mucoperiosteal flaps. Care was taken to preserve the maximum amount of inter-proximal soft tissue. Thorough defect debridement and root planing were performed using ultrasonic instrumentation⃰ * and area-specific currets††. No osseous recontouring was performed. One hundred and twenty six patients were finally considered as ten of them were excluded during surgery (because they did not present with 3 walled IBD’s.) In group 1 (OFD group, 32 patients), only open flap debridement was done, without addition of any regenerative material in to the bone defect. However, in group 2 (OFD plus PRF group, 32 patients), PRF of the required size was filled into the IBD after OFD. In group 3 (OFD plus MF gel group., 31 patients), 10 µl of 1% MF gel was inserted into the IBD after OFD. Whereas, in group 4 ( OFD plus 1% MF plus PRF group, 31 patients), equal amounts of PRF and MF gel were mixed and then were inserted into the IBD after OFD. Compressed PRF membranes (2 PRF’s were used to make 1 PRF membrane) were adapted over the defects (in group 2, 3 and 4) in order to protect the PRF, 1%MF and PRF+1% MF in the defect space. The mucoperiosteal flaps were repositioned and secured in place using 3-0 nonabsorbable silk surgical suture‡ ‡. The interrupted or sling sutures were placed. The surgical area was protected and covered with periodontal dressing§§. Patients were given necessary post-operative instructions and oral hygiene instructions were reinforced.
4
Journal of Periodontology; Copyright 2015
DOI: 10.1902/jop.2015.140646
Postoperative Care: Antibiotics and analgesics (500 mg amoxicillin, TDS for 7 days; 500 mg metronidazole, TDS for 7 days and 800 mg ibuprofen, TDS) were prescribed, along with chlorhexidine digluconate rinses (0.12%) twice daily for 2 weeks. Periodontal dressing and sutures were removed 2 weeks postoperatively. Surgical wounds were gently cleansed with 0.12% chlorhexidine digluconate, and participants were instructed for gentle brushing with a soft toothbrush. Each patient was reinstructed for proper oral hygiene measures at 8 weeks postoperatively and examined weekly for 1 month post-surgery and again at 3 and 9 months.. No subgingival instrumentation was attempted at any of these appointments. Post-Surgical Measurements: Soft and hard tissue evaluation was performed 9 months post-surgery. Soft tissue measurements were repeated with previously used acrylic stents. For hard tissue reevaluation, a second IOPA of the same study site was performed, and IBD measurement was reassessed at 9 months. Primary and Secondary Outcome Measures: The primary outcome of the study was radiographic defect depth reduction from baseline to 9 months. The secondary outcomes included changes in PD, RAL, GML, mSBI, and PI in the 9 months duration. Statistical Analysis: The data were analyzed using statistical software‖‖. Power calculations were performed before the study was initiated. To achieve 90% power and detect mean differences of the clinical parameters between groups, 30 sites per group were required. The results were averaged (mean standard deviation) for each clinical and radiographic parameter at baseline and 9 months. mSBI and PI were expressed as absolute and relative counts and comparison was performed using Chi-square test. Normality assumption of the data was tested using the Shapiro-Wilk test. The difference between each pair of measurements was then calculated (baseline to 9 months). Paired t test was applied to assess the statistical significance between time points within each group for clinical and radiographic parameters. Analysis of variance and post hoc Scheffe´ test were applied to assess the statistical significance between time points among the groups for clinical and radiographic parameters. The mean intra-examiner standard deviation of differences in repeated PD measurements and RAL measurements was obtained using single passes of measurements with a periodontal probe (correlation coefficients between duplicate measurements; r = 0.95).
RESULTS: One hundred and twenty patients (120 sites) of 126 participants completed the study (Fig. 1), since, six of them failed to followup. All treated cases showed uneventful wound healing and the drug was well tolerated by all the patients. Table 1 shows the basic demographic characteristics of the study population. There were no statistically significant differences in the mean age and gender of the patients in all the four groups. Supplementary tables 1 and 2 in the online Journal of Periodontology show the characteristics of the defects in all the 4 groups.
5
Journal of Periodontology; Copyright 2015
DOI: 10.1902/jop.2015.140646
A reduction in both PI and mSBI was observed in all four groups at 9 months postoperatively, however, the reduction was not statistically significant among the four groups. (Table 2). This indicates that an equivalent oral hygiene was maintained by patients of all the groups all through the study. Mean ± SD values for clinical and radiologic parameters at baseline and 9 months are reported in Table 3. There was no statistically significant difference in clinical (PD, RAL, GML) and radiological (IBD) parameters when the four groups were compared at baseline. However, a statistically significant difference in these parameters was noted when these groups were compared at 9 months. Table 4 shows the mean changes in the clinical and radiologic parameters (from baseline to 9 months). Also see supplementary Figures 1 and 2 in the online Journal of Periodontology. PRF, 1%MF and PRF+1% MF sites presented with a significantly greater PD reduction than control sites at 9 months postoperatively (P ≤0.05). The reduction in PD was greater in PRF+ 1% MF group (4.90±0.31 mm) when compared to MF (3.93 ± 0.25mm), PRF (4.00±0.18 mm) and OFD group (3.00±0.18 mm). (Table 4). RAL gain was also greater in the PRF, MF and PRF+1% MF sites compared to control sites, the difference being statistically significant (p
