Effects Of Erythritol And Xylitol On The Biofilm Of Streptococcus Mutans

Caries is a kind of common and frequently-occurring disease. It is a chronic bacterialcondition characterized by the deminerlization of inorganic substance and the decompositionof organic matter. All the dental prosthetics can’t make tissue of tooth return to formercondition at the present time. So the prevention of caries is great important. Effects of xylitol,a substitute of sugar, on caries have been proved because of the similar saccharinity, tasteand physical and chemical properties with saccharose. It has been studied that erythritol hasinhibition to the population, adherence and acid production of Streptococcus mutans (S.mutans). But the mechanisms of the caries resistance is still needed to be researched.S. mutans is regarded as the main pathogenic bacteria of caries, because of its strong abilityto adhere to tooth surface to form complicated bacteria in plaque biofilms. In order toresearch the effect and the probable mechanisms of the caries resistance of erythritol, thestudy has compared effects of erythritol on adherence and the biofilm structure by confocallaser scanning microscopy (CLSM) of S. mutans to that of xylitol. The results may providetheoretical basis for erythritol to resist caries and also provide a new method for preventionof caries. This study includes two parts:PartⅠ: Effects of erythritol and xylitol on adherence of S. mutansObjective: To study effect of erythritol on adherence of S. mutans. Methods: Compare thecolony-forming unit(CFU) values of S. mutans in different mass fraction of2%,4%,6%,8%erythritol or xylitol, so obtain the effects of erythritol and xylitol on adherence of S. mutans.Results: The CFU values gradually decreased while the mass fraction of erythritol and xylitol increased. The CFU values of xylitol group were lower than that of erythritol group inthe same mass fraction. But the CFU values of erythritol group and xylitol group in massfraction of2%and4%did not have significant difference. Conclusion: Adhesive inhibitionsof erythritol and xylitol were similar, and the inhibiting effects increase with concentration.There was no significant difference in lower concentration. Xylitol had a greater inhibitioneffect than erythritol in higher concentration.PartⅡ: Effects of erythritol and xylitol on the biofilm structure of S. mutans.Objective: To study effect of erythritol on the biofilm structure of S. mutans. Methods:Compared effects of erythritol and xylitol on the biofilm structure of S. mutans by CLSM.Results: As the concentration of erythritol and xylitol increase, the thickness of biofilm wasthinner, the density of S. mutans decreased, the cohesiveness of S. mutans decreased, thepercentage of vital bacteria decreased. Effect of erythritol was better than that of xylitol inmass fraction of2%and4%, while effect of xylitol was better in mass fraction of6%and8%. Conclusion: Effects of erythritol and xylitol on the biofilm structure were similar, andeffects increase with concentration. Effect of erythritol was better in lower concentration,while effect of xylitol was better in higher concentration.