Dental caries incidence is higher in adults than children. Recent recommendations from both the Centers for Disease Control and an NIH Consensus Development Conference on dental caries call for clinical trials of caries prevention methods in caries-active adults. Little is known about the effectiveness of caries prevention methods in adults, and virtually no information exists with respect to prevention among adults who are at elevated risk for developing caries lesions. This application describes a clinical trial of an intervention to prevent dental caries in caries-active adults that is responsive to the CDC and Consensus Conference recommendations.