Effect of preventive measures in 50-60-year-olds with a high risk of dental caries.

Salivary and microbial conditions were examined in 124 50-60-yr-old patients attending a dental clinic of the Public Dental Health Service. They were then randomly divided into a control and a test group. Patients with low salivary secretion rate and buffer capacity and high numbers of mutans streptococci and lactobacilli in the test group received special caries preventive measures during 1 yr. In the control group all patients were given prevention according to routine procedures. The incidence of dental caries between the groups was compared. The risk patients in the control group developed 1.67 new carious lesions as compared to 0.19 in the test group. The difference was statistically significant (P less than 0.05). Also the numbers of mutans streptococci and lactobacilli were significantly lower in the risk patients in the test group after 1 yr compared with baseline values. After the experimental year all patients were treated according to routine procedures. Five years after the start of the study a new examination showed increased caries activity in the risk patients in the test group and the gain which had been made during the experimental year was almost lost.