Dental caries in susceptible fissures after prolonged fluoride application

Abstract
A prolonged fluoride application (PFA) method was used to treat susceptible fissures in 210 permanent 1st molar teeth in 79 children living in a fluoridated community. The development of caries in these fissures was followed for periods ranging from 2-4 yr. At the final examination, 82.8% of occlusal surfaces in the 2 yr group and 80.0% of those in the 3 yr group were free of detectable lesions. The corresponding value for the 4 yr group was 78.9%. The mean number of treatments of these surfaces with the PFA method ranged from 1.6 for the 2 yr group to 2.9 for the 4 yr group.