Effect of a 0.05% Neutral NaF Mouthrinse on Coronal and Root Caries of Adults1

Three‐year coronal and root caries increments were compared in adults rinsing with either a 0.05% neutral NaF mouthrinse or a placebo mouthrinse. 1006 subjects, initially 20–65 years old (mean age: 39.9 yrs). who resided in fluoride deficient communities used a fluoride or placebo mouthrinse daily in their homes and brushed with an A.D.A. accepted fluoride dentifrice provided by the study. After three years, 731 subjects remained. Compliance was good. There were no significant differences (t‐test, p≤ 0.05) in coronal DMFT, coronal DMFS, root DFT and root DFS between the two groups. In subjects exhibiting root caries at the final examination, the DF root surface increment was 25.1% less in the fluoride mouthrinse users compared to those using the placebo rinse, but this difference was not statistically significant. The only significant difference in the caries increment between the two study groups was found for the mesio‐distal root surfaces of 45–65 year old participants.