Continuous effect of pit and fissure sealing on S. mutans presence in situ.

PURPOSE The effect of sealants on S. mutans presence in situ was investigated. METHODS Four intact, fully erupted first permanent molars in each of 74 children, aged 6-8 years were required for inclusion in the study. Baseline examination included deft and plaque index. S. mutans presence on occlusal surfaces of the molars was evaluated, using a microbial replica method. Immediately after sealing the first permanent molars on one side, S. mutans presence in situ was re-evaluated, as well as three and six months thereafter. Three months after the initiation of the study, S. mutans presence was evaluated on the molars of the unsealed side, which were consequently sealed and re-evaluated immediately, and three months later. RESULTS Positive correlation was found between deft scores, plaque indices and microbial replica values, at baseline. Sealing caused a significant reduction in S. mutans levels on the treated occlusal surfaces, in vivo (P < 0.001), which lasted, in most cases, up to six months. CONCLUSIONS The data suggest that sealants enable a prolonged reduction of S. mutans presence in situ, indicating an additional prevention effect, by reducing one source of dissemination.