The effects of an amine fluoride/stannous fluoride and an antimicrobial host protein mouthrinse on supragingival plaque regrowth

Background: Chlorhexidine (CHX) - containing mouthrinses are recommended as adjuncts to mechanical oral hygiene. The problem associated with side effects, however, has stimulated the search for alternative antiplaque agents. The aim of this study was to investigate the plaque inhibitory effects of two mouthrinses containing amine fluoride/stannous fluoride (ASF) and antimicrobial host proteins (lactoperoxidase, lysozyme and lactoferrin; LLL), respectively. Methods: The study was an observer-masked, randomized 4x4 Latin square cross-over design balanced for carryover effects, involving 12 healthy volunteers in a 4-day plaque regrowth model. A 0.12% CHX mouthrinse and a saline solution served as positive and negative controls, respectively. On day 1, subjects received professional prophylaxis, suspended oral hygiene measures, and commenced rinsing with their allocated rinses. On day 5, subjects were scored for disclosed plaque. Results: The ASF rinse showed a significant inhibition of plaque regrowth in comparison to both saline and LLL solutions, but the lowest plaque indices were obtained with the CHX formulation (P <0.01). There were no significant differences between LLL rinse and saline (P >0.05). Such pattern of efficacy was the same in anterior and posterior teeth and in vestibular and lingual surfaces as well, with the exception of the lingual anterior surfaces. In these sites, differences between the CHX and ASF rinses were not significant (P >0.05). A significantly higher prevalence of side effects was found in subjects using the CHX product (P <0.0042). Conclusions: Although the effect on plaque regrowth observed with 0.12% CHX rinsing was superior to that with ASF, the ASF rinse was not associated with side effects. These findings, together with those from long-term trials, suggest that the ASF rinse may represent an effective alternative to CHX rinse as an adjunct to oral hygiene. On the contrary, the LLL rinse did not significantly inhibit plaque regrowth.