The effect of 3 mouthrinses on plaque and gingivitis development
J. Maruniak^-^ W. B. Clark'^ C. B. Walker'^ I. Magnusson'•^ R. G. Marks'•^ M. Taylor'-' and B. Clouser''^ ^Periodontal Disease Research Center, ^Department of Oral Biology, College of Dentistry, ^Department of Statistics, Division of Biostatistics, University of Florida, Gainsville, FL 32610, USA
Maruniak J, Clark WB, Walker CB, Magnusson I, Marks RG, Taylor M and Clouser B: The effect of 3 mouthrinses on plaque and gingivitis development. J Clin Feriodontol 1992; 19: 19-23. Abstract. The aim of this study was to evaluate the effect of 3 mouthrinses, Listerine Antiseptic® (thymol), Peridex® (chlorhexidine), Perimed® (povidone iodine and hydrogen peroxide), and a placebo (water) on the development of dental plaque and gingivitis, when used as the only oral hygiene procedure for 14 days. 71 subjects were entered into a randomized, double-blind study. At the baseline examination, papillary bleeding score (PBS), and plaque index (PI) were registered, after which subjects received supragingival prophylaxis and were assigned to 1 of 4 study cells. Subjects were asked to refrain from all oral hygiene procedures except for the supervised 14-day 2 x daily rinsing with the assigned preparation. At day 14, the same clinical parameters were again registered. Statistical analysis was performed by a one-way analysis of variance (ANOVA) to compare the 4 groups, followed by Duncan's multiple range test to determine specific group differences. At baseline, average PBS and PI scores were similar for all 4 groups. After 14 days, the average PBS for Peridex® and Perimed® was significantly lower than for Listerine Antiseptic® and water. The frequency of interdental units with a PBS > 2 was significantly lower for Peridex® and Perimed® than for Listerine Antiseptic®' and water. We concluded that both Peridex® and Peritned® were effective in reducing plaque and gingivitis when used as a 2 X daily mouthrinse by subjects refraining from other oral hygiene procedures. In vitro, a synergistic effect was assumed when inhibition was achieved with Perimed® at the same or greater dilution than was achieved with povidone-iodine alone.
It is impossible to eliminate plaque completely from all tooth surfaces and every sulcus every day. Limiting factors include lack of dexterity and motivation, as well as difficult access (because of oral anatomy). An effective adjunctive treatment, other than mechanical methods, is needed to control gingivitis and plaque. Using an experimental gingivitis model described by Loe et al. (1965), various antimicrobial agents have been shown to effectively reduce plaque and gingivitis. (For reviews, see Hull (1980), Kornman (1986)). In a trial using 2 chlorhexidine gluconate concentrations (0.12% and 0.20%) against a placebo, Segreto et al. (1986) found that after 3 months, the 0.12% chlorhexidine gluconate demonstrated 27-31% less plaque and 28-33% less gingivitis severity than the placebo. This study found no significant difference between the 2
different chlorhexidine gluconate concentrations. Although many other antimicrobials have been tested, none have been shown to provide microbial and clinical benefits to the extent provided by chlorhexidine gluconate (Lang & Brecx 1986). Consequently, this agent represents the ideal positive control when testing the efficacy of other agents. Wennstrom & Lindhe (1979), during a two-week period in which HjO, was the only oral hygiene measure used, found that plaque and gingivitis were significantly reduced when compared with a placebo. During a 24-week period, Clark et al. (1989) found that the combination of povidone-iodine and hydrogen peroxide was significantly more effective against plaque and gingivitis than either product alone. In a study comparing Listerine
Key words: plaque; gingivitis; antimicrobial mouthrinse. Accepted for publication 24 October 1990
Antiseptic® to a placebo in inhibiting plaque formation (Fornell et al. 1975), subjects rinsed 3 x daily for 14 days as the only form of oral hygiene. Listerine Antiseptic® resulted in 53% reduction in mean plaque scores, 93% reduction in plaque wet weight, and 47% reduction in mean gingivitis scores. Other studies which employed a 7-14 day experimental gingivitis model noted mean plaque scores which were 20% (Lusk et al. 1974) to 45% (Gomer et al. 1972) lower for Listerine Antiseptic® than for a placebo. However, Carter et al. (1975) found no reduction in plaque when the essential oils preparation was used as a 2 X daily rinse, and Siegrist et al. (1986) found that Listerine Antiseptic® allowed significant gingivitis, plaque accumulation, and gingival bleeding to occur with no reduction in pathogenic plaque bacteria in vivo
Maruniak et al.
during a 21-day supervised 2 x daily rinse using the experimental gingivitis model. Simply stated, plaque is responsible for gingivitis (Loe et al. 1965). Kornman (1986) also states that since gingival infiammation is one of the sequelae to the proliferation of plaque micro-organisms, the goal of any therapeutic agent should be to substantially inhibit plaque formation. The aim of this study was to evaluate the effect of Listerine Antiseptic® (;thymol), Peridex® (0.12% chiorhexidine gluconate), Perimed® (povidone-iodine and H2O2), and water on the development of dental plaque and gingivitis when used as the only oral hygiene procedure during a 14-day supervised 2 X daily rinse. Material and Methods In vitro evaluation
Strains tested. Table 1 lists the strains tested. Type strains of each of the 6 species tested were purchased from the American Type Culture Collection (ATCC) immediately prior to the study. All other strains were obtained from the culture collection of the Periodontal Disease Research Center (PDRC), University of Florida. These latter strains were orginally isolated from patients with periodontitis and were characterized and identified to species level by conventional methods (Holdemann et al, 1977). Mouthrinses tested. The mouthrinses tested and their active ingredients were as follows: Listerine Antiseptic® (thymol), Peridex® (chiorhexidine), and Perimed® (povidone iodine and hydrogen peroxide). With the exception of Perimed®, all mouthrinses were obtained commercially. Media. Prior to testing, PDRC strains were taken from frozen stock by inoculating Trypticase-soy agar (TSBA), supplemented with 5% whole defibrinated sheep blood, hemin, and menadione, with 0.1 ml of the culture from a cyrovial ampule and incubating at 37°C, 60% relative humidity, in an anaerobic chamber containing 85% N2, 10% H2, and 5% CO2. All strains were examined for purity by both cellular and colotiial morphology. From this point, all strains were maintained on TSBA in the anaerobic chamber and transferred weekly. Broth cultures were initiated by inoculating 48-h colonies grown on TSBA into pre-reduced, anaerobically
sterilized Mycoplasma broth base medium under anaerobic conditions. Broth cultures were incubated for 48 h at 37°C prior to use. Determination of minimum bactericidal concentrations (MBCs). MBCs were determined by a modification of the method of Caufield et al. (1987). Cellulosic membrane filters, 82 mm in diameter, 0.45 /am pore size (MSI: Fisher Scientific Co.) were sterilized for 15 min at 12rC, Sterile forceps were used to place the filters carefully onto the surface of freshly prepared TSBA so that no air pockets existed between the membrane and the medium. After 24 h, the surface of the membrane was inoculated with 0.3 ml of 48 h broth culture. The inoculum was spread over the surface ofthe membrane with sterile cotton swabs at room atmosphere. The membrane-containing plates were immediately transferred into the anaerobic chamber and incubated for 48 h at 37°C. With the exception of Perimed®, all mouthrinse concentrations tested were prepared by withdrawing the mouthrinse from a freshly opened bottle purchased within the past 10 days and making a series of 2-fold dilutions in sterile distilled water. 10 concentrations ranging from 1:1 (full-strength) to 1:512 were tested for each ofthe mouthrinses. Perimed® was tested by withdrawing povidone-iodine (PVPI) and hydrogen peroxide (H2O2) from a freshly opened Perimed® package, combining the 2 components together in equal volumes, and then performing the series of dilutions. PVPI and H2O2 were tested as individual components by withdrawing a volume of each from the previously opened Perimed® package and then making a series of separate dilutions for each component. Therefore, the fullstrength PVPI-H2O2 preparation contained only one-half the PVPI and H2O2 concentration as did the full-strength PVPI and H2O2 tested separately. All dilutions were performed immediately prior to use for determination of MBC values. All dilutions of a particular mouthrinse or component were tested together by placing 0.2 ml of the dilution into a well of a replicating device (Cathra Replicating System), India ink was placed in a top well to serve as a reference point. A point inoculator attached to the rephcating device was used to pick up the mouthrinse concentrations from the 10 wells and transfer it to the
surface of membrane-containing plates which contained a 48-h-old bacterial lawn. Approximately 10 //I of each dilution was delivered to the surface of the membrane. Variation due to pipeting errors, growth conditions, etc were avoided by inoculating all 10 concentrations onto the same plate. The membranes were left on the surface of the TSBA plates for 5 min, then removed with sterile forceps and gently placed on the surface of fresh TSBA medium (prepared the previous day) which contained 40 //g/ml of triphenyl tetrazolium chloride (TTC). These plates were immediately placed in the anaerobic chamber. TTC served as an indicator of cell viability. The lawn of bacteria which had not been exposed to the mouthrinse as well as the areas exposed to sublethal concentrations of mouthrinse reduced the TTC and yielded a pink-tored color on the surface of the white membrane. Areas exposed to lethal concentrations of mouthrinse remained white against the surrounding pink-red background. The MBC was defined as that concentration of the mouthrinse that killed the bacteria within the zone in which the mouthrinse was applied (as determined by the absence of TTC reduction). The MBC determined for a particular bacterial strain was based on 3 separate determinations with duplicate plates used in each replication. In vivo evaluation
Subjects. 71 subjects were entered in a randomized double-blind study to evaluate the comparative efficacy of four mouthrinses. Inclusion criteria included the following: (i) men and women ages 18-55 in good overall health; (ii) pre-existing plaque and gingivitis; (iii) minimum of 20 sound natural teeth (fully crowned or restored, orthodontically banded teeth were not included in the count); (iv) minimum plaque mean >1.95 (Quigley & Hein 1962); (v) minimum papillary bleeding score, mean > 1.95. Exclusion criteria are listed below: (i) gross oral pathology as assessed by investigator; (ii) concomitant use of antibiotics and anti-infiammatory agents; (iii) hypersensitivity to iodine or shellfish. The subjects were not taking anti-
Effeet of mouthrinses on plaque and gingival development
Table 1. Minimal bactericidal concentrations of Listerine Antiseptic®, Peridex®, Perimed®,, and the two Perimed® components to 6 species of oral bacteria ' Lowest dilution resulting in non-viable cells Bacterial species
ATCC 33277 12R10-9 R20-18 ATCC 33563 R20-41 R20-50 33-26-23 ATCC 25586 R7-29 R20-62 R20-17 ATCC 19246 R19-62 R8-69 R4-24 ATCC 29522 ATCC 33384 12R11/1-19 12R10-4 12R11/1-18 ATCC 27872 249-2 R8-41
1/8" 1/16 1/8
1/4 1/8 1/4 1/4 1/4 1/8 1/4 1/32 1/16 1/16 1/8 1/16 1/4 1/32 1/4 1/8 1/16 1/8 1/32 1/8 1/8 1/8 1/4
1/8 1/8 1/16 1/8 1/16 1/16 1/32 1/4 1/8 1/8 1/16 1/4 1/8 1/8 1/8 1/32 1/4 1/8 1/16 1/8
Listerine Antiseptic® 1/1 1/1 1/1 1/1 >1/1 1/1 >1/1 1/1 1/1 1/1 1/1
l/l"" >1/P' 1/2 1/1 1/2 1/1 >1/]
1/4 >1/1 1/1 >1/1 1/1 1/1 1/2 1/1 >1/1 >1/1 1/1 1/1 1/1 1/1
>1/1 >1/1 >1/1 1/1 1/1 > 1 /1 1/1 > 1/1 1/1
Peridex" 1/1 >1/1 1/1 1/1 1/1 1/1 1/1 1/2 1/1 1/1 1/1 1/4 1/1 1/2 1/2
1/2 >1/1 1/1 1/1 1/1
"' Perimed" consisted of equal volumes of 10% povidone-iodine and 3% hydrogen peroxide, *" Povidone-iodine component, '^' Lowest twofold dilution of full-strength mouthrinse or component which resulted in clearly defined non-viable cells after 5 min exposure, '" Indicates undiluted mouthrinse or component, '• Indicates that bacteria were not killed by undiluted mouthrinse or component.
biotics or other medications known to affect the gingival tissues. Demographic information is listed in Table 2. The average papillary bleeding score for all subjects was 2,42, Study design. 22 subjects were randomly assigned to the 3 study products and 5 subjects were assigned to the placebo group. Subjects were asked to refrain from all other oral hygiene procedures except for the 14-day twice-daily 30-s supervised rinsing with the assigned products. The minimal time interval between rinses was 8 h, 4 mouthrinses were administered: Listerine Antiseptic'® (20 ml), Peridex* (15 ml), Perimed® (10 ml), and water
(20 ml), Listerine Antiseptic® contains eucalyptol, thymol, methyl salicylate, and menthol as the active ingredients. Peridex'"' is a 0,12% chlorhexidine gluconate solution. When mixed'!,!Perimed® results in a solution containii^g 5% povidone-iodine and 1.5% hydrogen peroxide. The water contained a small amount of certified food coloring. Clinical evaluation. At the baseline and 14-day examinations, papillary bleeding score (PBS; Loesche 1979) and plaque index (PI; Quigley & Hein 1962) were registered (score range, 0 to 5), After baseline measurements were recorded, the teeth of all subjects were disclosed, scaled, and polished to re-
move all supragingival calculus and plaque. The order of examination was as follows: condition of soft tissue, bleeding score, and plaque index. Statistical anaiysis
A one-way analysis of variance (ANOVA) was used to compare the groups at baseline with regard to PBS and PL Statistically significant results were followed by Duncan's multiple range test to determine specific group differences. Results in vitro evaiuation
Table 2, Demographic information by study group Perimed"
Water Age (years)
Oral contraceptive use
3 2 1 ••
• - 4
P 0,70 34 37
Table 1 summarizes the MBC determined for each strain to the 3 mouthrinses and the 2 Perimed® components. A synergistic effect was assumed when inhibition was achieved with Perimed® at the same or greater dilution than was achieved with PVPI alone. For example, in Table 1, P gingivalis ATCC strain 33277 was inhibited by a 1/8 dilution of Perimed® but required a 1 /4 dilution of PVPI for inhibition. The 1/8 Peri-
Maruniak et al.
Table 3. Comparison of groups by clinical measurements at baseline Listerine ® Peridex® Antiseptic Perimed® Water 57.27 67.50 55.18 60.40 total PBS 24.77 24.36 24.55 25.20 no. sites 2.71 2.35 2.24 2.39 average PBS 153.39 144.23 145.05 160.80 total PI 53.36 52.18 52.91 54.40 no. sites 2.70 2.80 2.90 2.97 average PI
P 0.04 0.78 0.04 0.42 0.60 0.81
baseline. ANOVA was used to compare the groups. There was no statistically significant difference between groups except for mean PBS. Duncan's multiple range test does not find any pairs of PBS means different at the 0.05 level of significance; however, the Listerine Antiseptic® group appears to have a larger mean PBS at baseline than the other 3 groups. The post-treatment analysis of PBS results will adjust for this difference. Table 4 presents the mean scores of each clinical measurement after 14 days. Peridex® and Perimed® do not differ significantly from each other on any measure, and are significantly superior to Listerine Antiseptic® and water for the 3 clinical measurements reported. Listerine Antiseptic® is superior to water only for PL Each analysis shown in Table 4 was rerun, using the baseline level of the measurement as a covariate. This analysis will account for any baseline differences among groups, such as appeared for PBS. None of the results shown in Table 4 changed from the covariate In vivo evaluation analysis, further documenting the validTable 2 presents baseline information ity of these results. on age, sex, smoking, and oral contraceptive use by treatment group. A oneway analysis of variance (ANOVA) showed no significant age difference among the 4 groups. The other cate- Discussion gories were not tested for statistical sig- The single research objective of this nificance because of the small number study was to evaluate the comparative of subjects in each cell. efficacy of Listerine Antiseptic®, PeridTable 3 presents a comparison of ex®, Perimed®, and water as inhibitors groups by clinical measurements at of dental plaque and gingivitis when
med® dilution corresponds to a PVPI concentration of 0.625%, while the 1/4 PVPI dilution contains 2.5% povidoneiodine. Based on the same calculations, no synergism was apparent for the following five strains: E nucleatum ATCC 25586, A. viscosus ATCC 19246, A. viscosus R8-69, A. actinomycetemcomitans ATCC 33384, and A. actinomycetemcomitans 12R13-18. However, a synergistic effect was evident for 19 of the 24 strains tested when the inhibition of the absolute concentrations of PVPI and/ or H2O2 were compared to Perimed®. PVPf alone yielded MBCs at ^ 1 / 4 dilution which is equivalent to ^2,5%. The MBCs obtained for the H2O2 component were in excess of 3% (full strength) for 7 of the strains tested and at 3% for 10 of the others. Listerine Antiseptic® killed 17 of the 24 strains when tested at full strength, but was ineffective at less than full strength. Peridex®, a chlorhexidine-containing mouthrinse, killed all but 2 strains at full strength or less.
Table 4. Comparison of groups by clinical measurements after 14 days Listerine Peridex® Antiseptic® Perimed® Water PBS PI PBS>2
2.55^' 3.65"' 13.60"'
1.84"' 2.30"' 5.32"'
2.5P' 2.87"=' 13.64"'
1.94"' 2.20"' 5.86"'
P 0.0001 0.0001 0.0001
The />-value results from a one-way ANOVA to compare the 4 groups. Groups with the same superscript are not significantly different as determined by Duncan's multiple range test. After adjusting for a baseline level in clinical measurements, the analysis of results remains the same. • - •
used as the only oral hygiene procedure for 14 days. To compare the groups, PBS>2 was chosen, since scores of 0 and 1 indicate no bleeding. Using PBS as the least subjective scoring, the PBS>2 value of 5,32 (mean frequency of sites) for Perimed® is not significantly different from that of Peridex® (5,86) but is significantly lower than the value of Listerine Antiseptic® (13.64) and for water (13,60), An earlier calibration study (Magnusson et al. 1990) showed that the reproducibility of the PBS was superior to that of the gingival index (Pearson correlation coefficient of 0.95 versus 0.61) and therefore the PBS was chosen to characterize gingival infiammation. The high reproducibility of the PBS is in agreement with the reproducibility of the Eastman interdental bleeding index reported by Blieden et al. (1989). Peridex® and Perimed® were found to be significantly more effective in reducing plaque than either water or Listerine Antiseptic®. Listerine Antiseptic® was more effective than water in reducing plaque but no significant difference was found in the mean PBS for water and Listerine Antiseptic®. Using 0.12% chiorhexidine gluconate as a positive control, Perimed® performed well when compared to Peridex® and no significant differences were found when all indices were compared. The clinical results confirm the results of the in vitro testing of the products, which show that both Peridex® and Perimed® exhibit a strong antimicrobial effect. However, it is possible that a combination of 2 antimicrobial compounds may have a different in vivo effect than that exhibited by each of the compounds separately. In fact, synergy of antibacterial substances has been reported by Sabath (1986). Caufield et al. (1986) reported that the combination of povidone-iodine and hydrogen peroxide exerted synergistic bactericidal effects against 4 out of 6 periodontopathogens and additive effects on the other two species in an in vitro model. Moreover, in a pilot study (Clark et al., unpublished data), the combination of Peridex® (used as a rinse 4 x daily) and Perimed® (1 x daily) was found to be more effective in preventing oral mucositis in neutropenic bone marrow transplant patients than either rinse used alone. This study concludes that Perimed® used as a 2 X daily rinse is as effective
Effeet of mouthrinses on plaque and gingival development Le but de la presente etude a ete de comparer les effets de la Listerine Antiseptic® (thymol), du Peridex® (chlorhexidine), du Perimed® (iodine de povidone et peroxyde d'hydrogene) et d'un placebo (eau) sur !e developpement de la Acknowledgements plaque dentaire et de la gingivite, lorsqu'ils This study was supported by a grant etaient utilises comme unique moyen d'hygiene buccale pendant 14 jours, 71 sujets ont parfrom Glenbrook Laboratories, a Divi- ticipe a cette etude au hasard et a double insu, sion of Sterling Drug Inc. We thank Jen- Lors de I'examen initial les scores d'indice de ny van Mill for typing and editing assist- plaque (PI) et de saignement papillaire (PBS) ance in the preparation of this manu- ont ele enregistres, Les individus ont ensuite re9u un detartrage et polissage avant d'etre rescript. partis en 4 groupes, I! leur a ete demande d'arreter toute mesure d'hygiene buccale sauf le Zusammenfassung rin^age supervise 2 x par jour pendant 14 jours, Au jour 14, les memes parametres ont Der Einfluss von drei MundspUlflUssigkeiten ete notes, L'analyse statistique a ete faite par auf die Entwicklung der Plaque und der Gingianalyse de variance en un sens pour comparer vitis les 4 groupes, suivie par le test a direction muiMit dieser Studie sollte der Einfluss von drei tipie de Duncan pour determiner les diffeMundspiiiniissigkeiten, namlich Listerine rences intra-groupes, Lors de I'examen initial Antiseptic® (Thymol), Peridex® (Chlorhexiles scores PI et PBS moyens etaient sembiabies din), Perimed* (Povidon-Jod und Wasserdans les 4 groupes, Apres 14 jours, le PBS dans stoffsuperoxyd), sowie von einem Plazebo les groupes Peridex® et Perimed® etait signifi(Wasser) auf die Entwicklung dentaler Plaque cativement inferieur que dans les deux autres und Gingivitis bestimml werden, Diese Mittel groupes, De meme, la frequence d'unites interwaren wahrend eines 14 Tage langen Versuchs dentaires avec un PBS > 2 y etait significativeals einzige mundhygienische Massnahme zument inferieure que dans les groupes Listerine gelassen, 7! Probanden nahmen an dieser ranAntiseptic* et placebo, Peridex* et Perimed® domisierten Doppelblindstudie teil, Anlasssont tous deux capab!es de reduire la p!aque et lich der Eingangsuntersuchung wurde die Pala gingivite lorsqu'ils sont utilises 2 x par jour pillenblutungs-Score (PBS) und der Plaque comme unique source d'hygiene buccale. In Index (PI) registriert, Danach wurden die Provitro, un effet synergique etait anticipe car l'inbanden supragingival prophylaktisch behanhibition avait ete produite avec le Perimed® delt und einer der vier Teilstudien zugeteiit. a la meme ou a une plus importante dilution Die Versuchspersonen wurden angehalten, qu'avec l'iodine de povidone seule. auf alle oral Hygienemassnahmen zu verzichten - mit Ausnahme von iiberwachten, 14 tagigen, zweimal am Tag vorgenommenen SpiiReferences lungen mit einer der zugeteilten Mundspu!Blieden, T, Caton, J,, Poison, A, M,, Proskin, fliissigkeiten. Am Versuchstag 14 wurden die H, M,, Stein, S, & Wagener, C, (1989) oben genannten Parameter wiederum regiExaminer reliability for the Eastman Interstriert. Die statistische Analyse zum Vergleich dental Bleeding Index, Journal of Dental zwischen den 4 Gruppen wurde mit einer einResearch 68, 196, abstr, 120, wegigen Varianzanalyse (ANOVA) vorgenommen, Daran anschliessend ermittelte Carter, H, G, & Barnes, G, R (1975) Effects of Duncan's mu!tip!er Spannweiten-Test die spethree mouthwashes on existing dental zifischen Gruppenunterschiede, Bei der Einplaque accumulations. Journal of Prevengangsuntersuchung waren die Beurteilungstive Dentistry 2, 6-11, einheiten fiir PBS und PI bei alien Gruppen Caufield, R W, Allen, D, N, & Childers, N. K, etwa gleich, Nach 14 Tagen war der durch(1987) In vitro susceptibility of suspected schnittliche PBS-Index fur Peridex® und Periperiodontopathic anaerobes as determined med" signifikant niedriger als fur Listerin Anby membrane transfer assay, Antirincrobial tiseptic" und Wasser. Die VorkommenshauAgents and Chemotherapy 3 1 , 1 9 8 9 - 1 9 9 3 , figkeit interdentaler Einheiten mit einem PBS Caufield, R W, Allen, D, N, & Childers, N, von > 2 war fur Peridex* und Perimed" signiK, (1986) Bactericidal effect of iodine and fikant geringer als fur Listerine Aseptic® und hydrogen peroxide against suspected perioWasser, Wir folgerten, dass Spulungen mit sodontopathogens, Jownal of Dental Rewohl Peridex* als auch Perimed®, bei taglich search 65, 267, abstr, 883, zweimaliger Anwendung als einzige zugelasseClark, W, B,, Magnusson, I,, Walker, C, B, & ne Hygienemassnahme, Plaque und Gingivitis Marks, R, G, (1989) Efficacy of Perimed® effektiv reduzierten. In vitro wurde bei der Inantibacterial system on eslab!ished gingihibition mit Perimed'-" ein synerger Effekt bei vitis (I), Clinical results. Journal of Clinical gleicher oder grosserer Verdunnung erreicht, Periodontology 16, 630-635, als mit Povidon-Jod alleine. Forne!!, J., Sundin, Y, & Lindhe, J, (!975) Effect of Listerine on dental plaque and gingivitis, Scandinavian Journal of Dental ReResume search %3, 18-25, Gomer, R, M., Holroyd, S, V, Fedi, R F, & Effet de trois bains de bouche sur le developpeFerrigno, R D, (1972) The effects of oral ment de la plaque et de la gingivite
as Peridex® in reducing plaque and gingivitis and superior to both Listerine Antiseptic® and water.
rinses on the accumulation of dental p!aque. Journal of the American Society for Preventive Dentistry 1, 12-14, Holdeman, L, V, Cato, E, P. & Moore, W, E, C, (1977) Anaerobe Laboratory Manual. Blacksburg: Virginia Polytechnique Institute and State University, Hull, R S, (1980) Chemical inhibition of plaque. Journal of Clinical Periodontology 7,256-267. Kornman, K, S, (1986) The role of supragingival plaque in the prevention and treatment of periodontal diseases, A review of current concepts. Journal of Periodontal Research 21 (Suppl, 16), 5-22, Lang, N, R & Brecx, M, C, (1986) Chlorhexidine digluconate - an agent for chemical p!aque contro! and prevention of gingival inflammation. Journal of Periodontal Research 21 (Supp!, 16), 74-89, Loesche, W, (!979) C!inica! and microbio!ogica! aspects of chemotherapeutic agents used according to the specific p!aque hypothesis. Journal of Dental Resarch 58, 2404-2412, Loe, H,, Theilade, E, & Jensen, S, B, (1965) Experimental gingivitis in man. Journal of Periodontology 36, 177-187, Lusk, S, S,, Bowers, G, M,, Tow, H, D,, Watson, W. J, & Moffitt, W, C, (1974) Effects of an oral rinse on experimenlai gingivitis, plaque formation, and formed plaque. Journal of the American Society for Preventive Dentistry 4, 31-34, Magnusson, I,, Taylor, M,, Clark, W, B., Clouser, B, & Maruniak, J, (1990) Intra- and inlerexaminer correlations of some oral indices. Journal of Dental Research (Special Issue) 69, 355, abstr, #1970, Quigley, G, A, & Hein, J, W, (1962) Comparative cleansing efficiency of manual and power brushing. Journal of American Dental Association 65, 26-29. Sabath, L, D, (1968) Synergy of antibacterial substance by apparently known mechanisms. Antimicrobial Agents and Chemotherapy 1967, 2W-2\7. Segreto, V, A,, et al, (1986) A comparison of mouthrinses containing two concentrations • of chlorhexidine. Journal of Periodontal Research 21 (Suppl, 16), 23-32, Siegrisl, B, E,, Gusberti, F, A,, Brecx, M, C, Weber, H. R & Lang, N, R (1986) Efficacy of supervised rinsing with chlorhexidine digluconate in comparison to phenolic and plant alkaloid compounds. Journal of Periodontal Research 2i (Suppl, 16), 60-73, Wennstrom, J, & Lindhe, J, (1979) Effect of hydrogen peroxide on developing plaque and gingivitis in man. Journal of Clinical Periodontology 6, 115-130, Address: Ingvar Magnusson Periodontal Disease Research Center Department of Oral Biology Box J-424 JHMHC University of Florida Gainesville, FL 32610 USA