Bleeding on probing (BOP) is a widely used criterion to diagnose gingival inflammation. The purpose of the present retrospective study was to evaluate its prognostic value in identifying sites at risk for periodontal breakdown during the maintenance phase of periodontal therapy. 55 patients who had been treated for advanced periodontitis participated in a recall system for at least 4 years, at regular intervals of 3-5 months. At the start of every appointment, BOP to the bottom of the pocket was registered at 4 sites of every tooth. A random selection of 1054 pockets was made and subdivided into 5 categories according to the incidence of BOP during the last 4 recall appointments. All pockets with a BOP incidence of 4/4 and 3/4 were selected, while only interproximal sites with a BOP incidence of 2/4, 1/4 and 0/4 were chosen. Subsequently, these categories were grouped according to whether or not the attachment level had been maintained from the time prior to the last 4 recall visits. Greater than or equal to 2 mm was defined as loss of clinical attachment. The results indicated that pockets with a probing depth of greater than or equal to 5 mm had a significantly higher incidence of BOP. Patients with 16% or more BOP sites had a higher chance of loosing attachment. Pockets with an incidence of BOP of 4/4 had a 30% chance of loosing attachment. This chance decreased to 14% with BOP of 3/4, 6% with BOP of 2/4, 3% with BOP of 1/4 and 1.5% with BOP of 0/4.(ABSTRACT TRUNCATED AT 250 WORDS)

Different studies have shown that various substances may have an influence on early human dental plaque formation. The purpose of the present study was to compare on tooth substances and supporting prosthetic materials the amount of plaque deposition by SEM and the quantity of selected bacteria using anaerobic culturing techniques. 5 bridges, replacing a missing molar or premolar, were incorporated in 3 patients. In the midbuccal area of each pontic, a semi-precision attachment was placed allowing the insertion of the following test facings: enamel, dentine, non gamma 2-amalgam, alloys of 85% and 55% gold, silver-palladium, chrome-cobalt, chrome-cobalt-titanium, and ceramic. For each material, 2 facings were fabricated. After 4 and 24 hours in situ, bacteriological samples were taken and processed for further identification. After a 2nd period of 4 and 24 hours in situ, the same facings were carefully removed and prepared for SEM-examination. All 4-hour specimens exhibited various areas covered by plaque, the amount of which varied with the different supporting substances. The very smooth surfaces (e.g., gold) harbored sparse deposits, while the rougher (e.g., amalgam) were covered by more plaque. After 24 hours of plaque development, an increase in the number of micro-organisms was noted for all the specimens. After 4 and 24 hours of plaque accumulation, no specific trends suggesting a preferential colonization on the different substances were observed. This study has shown that the amount of early deposits on different substances seems to be related to the degree of their surface roughness, while plaque formation was qualitatively similar.

The experimental gingivitis model was used to compare the antigingivitis, antiplaque, and antimicrobial efficacies of two commercially available (a phenolic and a plant alkaloid) compounds used as mouthrinses with those of a mouthrinse containing chlorhexidine digluconate. Thirty‐one male and female volunteers with healthy gingivae and clean teeth ceased all oral hygiene procedures for 21 days during which they rinsed twice daily with: a) a phenolic compound (Listerine®), b) sanguinarine (Viadent®), c) 0.12% chlorhexidine digluconate, or d) a placebo mouthrinse. After 21 days of rinsing, virtually no signs of clinical gingivitis were observed in the chlorhexidine group. Subjects rinsing with Listerine, Viadent, or placebo developed clinical signs of gingivitis as measured by gingivitis occurrence, severity, and the proportion of gingival bleeding sites. At the same time, plaque accumulation was only slightly higher than at baseline in the chlorhexidine group, while the Listerine, Viadent, and placebo groups had significantly greater plaque accumulations, particularly during the initial period of treatment between day 0 and day 7. Microbiological enumeration of supragingival plaque collected at the end of the treatment period showed that chlorhexidine digluconate reduced plaque bacteria by 62–62% compared to the placebo group. No significant reductions in plaque bacteria were found among subjects using Listerine or Viadent. This study demonstrated that 0.12% chlorhexidine digluconate was superior to Listerine and Viadent in its ability to maintain optimal gingival health during the entire three weeks of mouthrinse use. It was of particular interest to note these effects during the final 14 to 21‐day period of extreme challenge in this experimental model when gingivitis severity and bleeding site occurrence are most pronounced in the placebo group.

While the ability of chlorhexidine (CHX) to prevent plaque formation and inhibit the development of gingivitis has been well documented in the literature, the therapeutic value of hydrogen peroxide (H2O2) in preventing gingivitis is in dispute. The purpose of this study was to compare the clinical and microbiological effects of an established therapeutic agent, such as chlorhexidine with that of H2O2 in the experimental gingivitis model. Following a period of stringent oral hygiene, 32 subjects were allocated to 1 of 3 treatment groups which were balanced on the basis of their pre-experimental gingivitis scores. The subjects then refrained from any oral hygiene for 21 days. During this period, they rinsed twice a day with either a placebo, 0.12% CHX, or a 1% H2O2 mouthrinse. After 21 days, supragingival and marginal plaque was collected from each subject and assayed for total cultivable microbiota, total facultative anaerobes, facultative Streptococci, Actinomyces, Fusobacterium, Veillonella and Capnocytophaga. At the end of the experimental period, the group rinsing with 0.12% CHX showed 95% reduction in gingivitis incidence, 100% reduction in bleeding sites, and 80% reduction in plaque scores compared to the group rinsing with placebo. Conversely, the group using 1% H2O2 showed a marginal reduction in gingivitis incidence of 15% and a 28% reduction in bleeding sites compared to the placebo group, but no significant reduction in plaque scores. The microbiological results showed that 0.12% CHX was an excellent broad-spectrum antimicrobial agent which significantly reduced the number of both facultative and obligate anaerobes in plaque.(ABSTRACT TRUNCATED AT 250 WORDS)