Reduction in proportions of dental plaque streptococci following a 5 day topical kanamycin treatment

A 5 day topical kanamycin treatment of the dental gingival surfaces in institutionalized mentally retarded subjects significantly reduced the plaque mass on the tooth surfaces compared to a placebo treatment. This reduction occurred in the absence of any mechanical hygiene procedures and lasted for 4 or more weeks, which was longer than the kanamycin could have been expected to be present in the mouth. This suggested that the kanamycin had caused an alteration of the plaque flora which should be discernible by quantitative culturing procedures. Plaque was removed and cultured, using an anaerobic serial dilution procedure, before and after kanamycin or placebo treatments. The reduction in plaque weight was associated with reduced levels of streptococci in the plaque. This could be demonstrated by intergroup comparison of the placebo - and kanamycin treated subjects, and by intragroup comparisons of the kanamycin treated subjects prior to treatment and at 4 and 8 weeks after treatment. The streptococci species accounted for 30% of the plaque colony forming units (CFU) prior to kanamycin treatment. At 4 weeks after treatment, the streptococci had decreased to 3% of the CFU and at 8 weeks after treatment, the streptococci had increased slightly to account for 14% of the CFU. The streptococci appeared to be Streptococcus sanguis and Streptococcus mitis . The observations indicate that the topical kanamycin was effective in reducing supragingival plaque because of its ability to decrease the proportions of streptococci in the plaque.     

Effect of gum chewing on plaque accumulation

The purpose of this investigation was to test the effect of chewing gum sweetened with either sorbitol (LG) or sucrose (SG) on the growth of plaque on tooth enamel surfaces. Nineteen dental students, in a balanced crossover design, chewed the two gums for 5 days without normal oral hygiene practices. The control treatment was a 5-day non-chewing (NG) phase. A period of 9 days was allowed for normal hygiene between test phases. The chewing regimen required 20 minutes of use of one stick of chewing gum immediately after meals or snacks. The average number of sticks chewed was 3.8/day. Pre- and post-treatment plaque scores were recorded by two examiners using a Modified Navy Plaque Index (PLI) from 0 to 9 along each of four surfaces to assess six Ramfjord teeth. Pre-treatment mean PLI scores for the 3 test treatments were, NG = 2.0, LG = 1.9 and SG = 1.9. Post-treatment mean PLI scores were, NG = 3.6, LG = 3.3 and SG = 3.3. ANOVA of pre- and post-treatment scores revealed no significant differences between treatments. Post-treatment scores of the 2 chewing gums were then pooled, independent of sweetener. ANOVA of these data revealed chewing gum (LG + SG = 3.3) to cause significantly less plaque accumulation than no gum (NG = 3.6). In a no oral hygiene environment, plaque accumulation during use of sorbitol chewing gum or sucrose chewing gum was statistically the same. However, chewing gum, irrespective of sweetener, caused significantly less plaque accumulation than no chewing.     

Reduction of supragingival plaque accumulations in institutionalized Down's syndrome patients by periodic treatment with topical kanamycin

A small group of institutionalized Down's syndrome patients were treated with topical kanamycin sulphate paste, once or twice a day for 3–5 days, every fifth week over a 52-week-period. The teeth were not brushed during this 52-week-period. The wet weight of the supragingival plaque in the kanamycin group was significantly reduced when compared to the supragingival plaque formed in the group receiving a placebo paste. The gingivitis score of the kanamycin group did not deteriorate during the period of antibiotic administration despite the absence of oral hygiene procedures. No increase in kanamycin-resistant bacteria or yeasts were detected in plaque or tongue samples during the period of kanamycin treatment.     

Effect of an antiseptic mouthwash on plaque accumulation.

This study was undertaken to determine the effect of sodium peroxyborate monohydrate bitartarate on plaque accumulation in comparison with "no oral hygiene" and "brushing once before breakfast." Fifteen male resident students between the ages of 18 to 22 years volunteered for the study. 1. In all three stages of the study regeneration of plaque were observed in all individuals within 24 hours after thorough prophylaxis. 2. The tendency to plaque accumulation varied from person to person, from tooth to tooth in the same individual, and even on different surfaces of the same tooth. 3. The plaque scores and the range of plaque scores were lower on the first 2 days with the use of mouthwash when compared with tooth brushing on the corresponding days. 4. A reduction of 30.62% was observed with the use of mouthwash when it was compared with "no oral hygiene." 5. Plaque accumulation was 17.7% more with mouthwash than with use of the toothbrush. 6. A negligible reduction in efficacy (0.38%) was observed with this mouthwash in comparison with 1% H2O2, used under pressure.     

Comparison of plaque accumulation after topical application and mouth rinsing with chlorhexidine gluconate

This study measured plaque accumulation on anterior teeth after topical or mouth rinse application of 0.2% chlorhexidine gluconate. Compared with water plaque scores were highly significantly reduced. There was no significant difference in plaque scores between topical application or mouth rinsing. The importance of locally adsorbed chlorhexidine is emphasised and the relevance of an oral reservoir effect questioned.     

Effect of localized experimental gingivitis on early supragingival plaque accumulation

Abstract Previous investigations have reported increased plaque formation in the presence of gingival inflammation as compared with gingival health. In these investigations, experimental gingivitis has been induced by total abolition of oral hygiene such that increased levels of salivary bacteria could contribute to the increased plaque formation. In the present study, experimental gingivitis was localized to 2 selected teeth whilst maintaining normal oral hygiene measures in the rest of the mouth. The aim of this study was to investigate whether the mass of plaque accumulating in a 3-day period is influenced by the inflammatory status of the adjacent gingival margins. Following scaling, prophylaxis and a period of optimal hygiene to establish gingival health, “plaque-guards” were worn during routine oral hygiene performance to prevent any cleaning on the buccal surfaces of teeth 14 and 15 from days 0 to 3. On day 3, accumulated plaque was removed from a 1.5 mm zone on the buccal surfaces of 14 and 15 adjacent to the gingival margins and weighed immediately. Subjects continued to wear their plaque-guards during oral hygiene until day 14 to induce experimental gingivitis around the experimental teeth. At day 14, all plaque was cleaned from the buccal surfaces of the experimental teeth and the mass of plaque accumulating over the next 3 days weighed on day 17. Comparison of plaque weights showed that the wet-weight of 3 day-old plaque was higher in the presence of experimental gingivitis than in the presence of gingival health (p= 0.02). This observation suggests that the inflammatory status of the marginal gingival has an important effect on early, supragingival plaque accumulation.     

Effect of an experimental dentifrice on plaque accumulation and gingival inflammation

A clinical investigation was done to determine the comparative efficacy of an experimental dentifrice, containing sodium bicarbonate, sodium chloride, zinc chloride, and sodium fluoride, with a control dentifrice on plaque accumulation and gingival inflammation. Fifty individuals participated in the study; 25 persons were randomly assigned to the control and experimental groups, respectively. The study was done using a double-blind protocol. Paired data t-test analysis was done to determine if statistically significant reductions in plaque accumulation and gingival inflammation had occurred after the 30-day test period, and if significant differences existed between the control and experimental groups. Both groups showed a statistically significant reduction in their gingivitis and plaque scores. Comparison of the two groups indicated a 52% greater reduction in gingival inflammation by the group using the experimental toothpaste. The ability of the two dentifrice formulations to remove plaque, however, was similar.     

Effect of the Water Pik® device on plaque accumulation and development of gingivitis

Abstract The influence of the water irrigating device. Water Pik®, on the accumulation of plaque and development of gingivitis has been studied using the model, “experimental gingivitis in man”. The investigation was carried out on 41 patient volunteers whose teeth were thoroughly scaled and polished during a 4-week period of intensive oral hygiene preceding each experimental period. Gingival exudation. Plaque Index and Gingival Index were registered at the beginning of the experimental periods. The participants were then divided into four groups. Groups A and B abandoned all forms of active oral hygiene. Group A, however, were given Water Pik devices as the only oral hygiene aid. Groups C and D continued to clean their teeth using a toothbrush and Group C were given Water Pik devices as a supplementary aid. After 14 days, gingival exudation. Plaque Index, Gingival Index and soft tissue injuries were registered. The results showed that, while both groups A and B demonstrated extensive plaqtie deposits and gingivitis, these were present to a significantly lesser degree in Water Pik users. The toothbrushing groups (C and D) failed to demonstrate any further reduction of plaque or gingivitis when Water Pik was introduced as an additional measure. No soft tissue injuries were found.     

Partial dentures and plaque accumulation

Damage to the oral tissues arises when the patients fail to adopt adequate oral hygiene measures. Partial dentures have been shown to increase the plaque formation and this is worse when teeth and gingivae are covered, as in lingual plate dentures. Attempts to show that ‘self-cleansing’ spaces between saddles and teeth collect less plaque than saddles fitted closely to the teeth were not successful.     

葡萄柚漱口液抑制菌斑形成的体内研究

目的:研究葡萄柚漱13液在体内对菌斑的抑制作用.方法:采用双盲一自身前后对照实验研究葡萄柚漱口液的菌斑抑制能力,并与口泰和西吡氯铵漱口液进行比较.结果:葡萄柚漱口液的菌斑抑制能力与西吡氯铵漱口液相比无显著差异,弱于口泰漱口液,且与另两种漱口液相比口感好,易被受试者接受.结论:葡萄柚漱口液作为一种新型天然植物提取物漱口液,具有良好的菌斑抑制效果.     

Reduced dental plaque accumulation on composite gold alloy margins

Restoration of tooth surfaces with materials that inhibit formation of heavy bacterial plaque accumulations could be important in the treatment of patients with existing oral disease or in reducing the likelihood for periodontal disease. Captek is a dental gold composite material used to produce copings for ceramometal restorations that has been reported to inhibit plaque accumulation. In this study, the oral bacteria of nine periodontally healthy subjects with a total of 42 gold composite copings were sampled. Contralateral teeth with normal tooth surfaces were also sampled as controls. The quantitative presence of forty bacteria was determined in each sample by DNA:DNA hybridization. The results indicated that the porcelain/gold composite alloy coping surfaces had significantly fewer bacteria than the control normal tooth surfaces (71% reduction). The percentage composition, however, did not differ significantly between surfaces.     

Effect of a mouthrinse containing selected propolis on 3-day dental plaque accumulation and polysaccharide formation

The aim of this study was to evaluate the effect of a mouthrinse containing propolis SNB-RS on 3-day dental plaque accumulation. Six volunteers took part in a double-blind crossover study performed in two phases of 3 days. During each phase the volunteers refrained from all oral hygiene and rinsed with 20% sucrose solution 5 times a day to enhance dental plaque formation and with mouthrinse (placebo or experimental) twice a day. On the 4th day, the plaque index (PI) of the volunteers was scored and the supragingival dental plaque was analyzed for insoluble polysaccharide (IP). The PI (SD) for the experimental group was 0.78 (0.17), significantly less than for the placebo group, 1.41 (0.14). The experimental mouthrinse reduced the IP concentration in dental plaque by 61.7% compared to placebo (p < 0.05). An experimental mouthrinse containing propolis SNB-RS was thus efficient in reducing supragingival plaque formation and IP formation under conditions of high plaque accumulation.     

Effects of topical application of chlorhexidine on plaque and gingivitis in monkeys

All teeth except the lower right canine, premolars and molars, in each of 4 adult male macaque monkeys with heavy plaque deposits and severe gingivitis, were scaled and polished daily for 5 days, followed by daily topical applications of 2% aqueous chlorhexidine gluconate. Minimal amounts of simple plaque containing epithelial cells and Gram positive cocci formed on the treated teeth whereas the untreated teeth retained heavy deposits of complex plaque. In chlorhexidine treated areras the clinical level of gingivitis appeared to subside to a minimum after 15-20 days. Histomorphometric assessments of gingivitis after 42 or 52 days treatment were made on decalcified paraffin sections, by measuring the total area of gingival connective tissue and the area containing inflammatory cells and calculating the proportion of gingival tissue affected. A total of 21 teeth were assessed. Untreated teeth had from 16-40% of the gingivba inflamed, treated teeth only 0-6%. Thus daily topical application of chlorhexidine significantly inhibits plaque accumulation and maintains a significant reduction in gingivitis in these animals. No differences in the nature or degree of keratinization could be detected between treated and untreated areas, nor were there any visible side effects of the use of chlorhexidine for this period.     

Initial gingivitis induced by topical application of plaque extract

The present study was undertaken to examine if soluble substances in human dental plaque were able to induce structural alterations in the marginal gingiva characteristic of initial gingival inflammation.
Four-day old plaque was sampled from dental students; the plaque material was pooled, suspended in saline, homogenized, centrifuged and filtered. The supernatant, the plaque-extract, was then, during an eight hour period, topically applied to the gingival margin of the upper jaws of five Beagle dogs. In control regions saline was applied in an identical manner. One and a half hour before sacrifice the animals were given i.v. injections of colloidal carbon.
Biopsies of test and control regions were taken according to a technique described by Schroeder et al (1973). The biopsy specimens were embedded in Epon. Semithin sections (2-3 μm) were examined in the microscope regarding 1. amount of vascular units subjacent to the junctional epithelium containing carbon particles
2. number of polymorphonuclear and mononuclear leucocytes within the junctional epithelium.
The examinations revealed that the gingival units exposed to plaque extract in comparison to controls harboured larger numbers of carbon labelled vascular units and larger numbers of leukocytes within the junctional epithelium. The data also showed that the main reaction occurred in the marginal portion of the gingival tissue. The observations of this study indicate that soluble substances from human dental plaque when applied topically in the gingival sulcus may give rise to structural alterations similar to those developing in the gingival tissues in response to plaque accumulation.