Sample size From previous studies, it was inferred that a mean colony forming unit (CFU) unit difference of approximately one log (standard deviation (SD) = approximately 1) would result in a clinically significant increase in S.mutans counts. Therefore the sample size of 15 participants per group, at α = 0.05, yielded a statistical power of approximately 0.80 for this study. To account for a 10-25% patient drop out and data loss due to other unavoidable circumstances, we will enroll 68 patients for this study.