Caries: a problem in an overdenture population.

A series of 254 patients who had their overdentures constructed at a University clinic from 1973 to 1985 were followed longitudinally. This paper reports on the caries experience in the abutment teeth of these patients. The mean age of the patients at the time of insertion of the dentures was 58.6 yr. The overall rate for new caries was 6.5% of the abutment teeth per year. The highest rate for the maxilla was 15.4%, which occurred during the 5th yr, and in the mandible it was 11.0%, which occurred in the 4th yr. A regression model was developed to profile individuals susceptible to caries. The Logistic Regression model identified a list of predictor variables which included frequency of brushing, use of home fluoride, and disease and drug effect. However, discriminant function analysis showed that although specificity was very high (98.5%), sensitivity was very low (7.9%). Therefore, this model was unable to predict persons who would be at high risk for caries.