The Results after 20 Months of a Study Testing the Efficacy Of a Weekly Fluoride Mouthrinsing Program

The purpose of this study was to determine the efficacy of weekly mouthrinsing with a 0.2 percent NaF solution in first-grade children living in a non- fluoridated community. Children in the control group were also participants in a randomized clinical trial to evaluate the efficacy of semiannual fluoride varnish treatments. Children allocated to the mouthrinse group attended school at three of the 17 area schools where the varnish study was occurring. Random allocation of children into the treatment group was considered impractical because of potential problems of teacher cooperation and compliance. The same two standardized examiners examined all participants, and were blind to group assignment for all children. After two academic years, or approximately 72 weeks of rinsing, 178 and 247 children remained in the treatment and control groups, respectively. The control group experienced a mean caries rate of 2.02 surfaces over 20 months, while the treatment group demonstrated an increment of only 1.33 surfaces, representing a savings of about 0.34 surfaces per year or a reduction in DMFS of 34.2 percent. Surface-specific incremental reductions after 20 months were 0.35, 0.19, and 0.14 for the occlusal, buccal, and lingual surfaces, respectively. The proximal increment was too small to draw any meaningful conclusions. In the primary dentition, the treatment and control dfs increments were 0.74 and 1.74, respectively. This reduction represents a savings of one-half surface increment per year, or a education of 57.5 percent.