Several dentifrices that contain hydrogen peroxide are currently being marketed. The increased use of bleaching agents containing (or generating) H2O2 prompted this review of the safety of H2O2 when used in oral hygiene. Daily exposure to the low levels of H2O2 present in dentifrices is much lower than that of bleaching agents that contain or produce high levels of H2O2 for an extended period of time. Hydrogen peroxide has been used in dentistry alone or in combination with salts for over 70 years. Studies in which 3% H2O2 or less were used daily for up to 6 years showed occasional transitory irritant effects only in a small number of subjects with preexisting ulceration, or when high levels of salt solutions were concurrently administered. In contrast, bleaching agents that employ or generate high levels of H2O2 or organic peroxides can produce' localized oral toxicity following sustained exposure if mishandled. Potential health concerns related to prolonged hydrogen peroxide use have been raised, based on animal studies. From a single study using the hamster cheek pouch model, 30% H2O2 was referred to as a cocarcinogen in the oral mucosa. This (and later) studies have shown that at 3% or less, no cocarcinogenic activity or adverse effects were observed in the hamster cheek pouch following lengthy exposure to H2O2. In patients, prolonged use of hydrogen peroxide decreased plaque and gingivitis indices. However, therapeutic delivery of H2O2 to prevent periodontal disease required mechanical access to subgingival pockets. Furthermore, wound healing following gingival surgery was enhanced due to the antimicrobial effects of topically administered hydrogen peroxide. For most subjects, beneficial effects were seen with H2O2 levels above 1%. J Periodontol 1995;66:786–796.

No abstract

These investigations included a wide range of dosage levels (0.05 to 2.0%) and considerable variability in treatment regimens. The present study was carried out to determine the minimum level of CG for antiplaque effectiveness consistent with safety of the agent under ordinary conditions of mouthwash use.Five oral rinses containing 0.0, 0.0067, 0.02, 0.06, and 0.18% of CG, respectively, were tested during a period of several weeks in a doubleblind study that used an incomplete block trial design. This is a standard statistical technique used in situations where each individual cannot undergo each and every treatment. In this study, each individual used a subset of the treatments such that a specific balance was maintained, that is, each participant used at least four of the five experimental rinses. Throughout the test period, the 17 adult male subjects alternately rinsed with 20 ml of one of the coded solutions three times daily for five days. During the first three days, the men brushed their teeth in their usual manner with a conventional nontherapeutic dentifrice. On days four and five, the participants refrained from brushing but continued to use their assigned rinses. Plaque was disclosed on the fifth day and scored by use of a modified Greene-Vermillion index. The subjects were "rested" for one week before rieassignment to another rinse. Our results indicated that at the lowest concentration, an 8% reduction occurred (Fig). At the 0.02% concentration, the inhibitory effect increased sharply to 30% and began to plateau at the 0.06% concentration where a 61% inhibition was obtained. Little additional benefit was obtained by tripling this concentration, (65% vs 61% inhibition).Comparison of our data with Schroeder's earlier study (1969) concerning Mylar strip plaquecalculus inhibition indicates some dissimilar ities for three comparable dose levels of CG tested in both laboratories. Basically, Schroeder's results do not indicate a plateau effect. These differences may perhaps be explained by different experimental techniques. Schroeder suggested that the agent (CG) was CHLORMEXIDINE GLUCONATE CONCENTRATION al)Relationship of CG concentrations to in vivo plaque inhibition on Mylar strips and teeth. preferentially more effective for subjects prone to rapid calculus-plaque buildup as opposed to those demonstrating a slower buildup. To determine whether the effects of the agent under evaluation preferentially inhibited dental plaque for those prone to heavy plaque buildup, the data were examined for differences between effecis on heavy formers vs light former. This arbitrary division was made by selecting the midpoint (1.5) of the scoring range. The distribution obtained from this division was seven light formers and ten heavy formers. Although there were slight differences between the groups at the 0.06 and 0.18% CG level (light plaque fosrness had lower scores), there were no statistically significant differences at any level.The findings of this studv suggest that (1) under a fixed regimen of oral hygiene, a ...

THE ROLE OF DENTAL PLAQUE in the generation of cal-culus is now well recognized. Until recently, inhibition of crystallization of the plaque to hydroxyapatite was emphasized as the route to the prevention of calculus deposits. This approach is now giving way to attack on the microbial component of plaque. Löe, 1 for example, reported elimination of dental calculus in subjects appropriately treated with the antimicrobial agent chlorhexidine gluconate. Calculus reduction by the use of chemical agents whose principal mode of action is not antimicrobial is still a subject of study, as exemplified by the recent work of Turesky et al. 2,3,4 using the chloromethyl analog of Victamine C † and the work of Mühle-mann et al. using 1-hydroxyethane-1, 1-diphosphonate. 5In a recent paper 6 it was reported that calculus accumulation could be markedly reduced by the self-administered application of an oral rinse comprising a complex of zinc with the antimicrobial agent tribromsalan plus zinc phenolsulfonate. The authors postulated that the efficacy of this oral rinse was attributable to its ability to interfere with the integrity of the plaque matrix and to its antimicrobial activity.In the current investigation, a similar oral rinse containing zinc citrate and zinc tribromsalan suspended in an aqueous medium was examined with respect to its effect on early plaque formation. It was considered likely that the incorporation of large amounts of the TABLE 1.

A 3-yr daily supervised toothbrushing study with a double blind design was conducted to evaluate the anticaries effectiveness of a 1.14% sodium monofluorophosphate (MFP) dentifrice (1500 ppm F) compared to a 0.76% MFP dentifrice (1000 ppm F). This study began with nearly 4000 children, primarily aged 8-11, in grades 3-5, residing in a nonfluoridated community in Florida. A total of 2415 children completed 3 yr of the study, representing 61% of the children who began the study. The results indicate a statistically significant (P less than 0.001) anticaries benefit was derived over a 3-yr period from the use of the higher fluoride dentifrice (1500 ppm F) when compared to the positive control (1000 ppm F). Percent reductions in mean dental caries increments were 20.9%, 22.1%, 21.8%, 24.3%, and 35.2% for DMFT, DFT, DMFS, DFS, and DFS Interproximal, respectively.