Microleakage of sealants after conventional, bur, and air-abrasion preparation of pits and fissures.

PURPOSE The aim of this study was to compare the microleakage of unfilled and filled sealants after conventional, bur, and air-abrasion tooth preparation. METHODS Seventy-two extracted molars were randomly divided into three groups. In group 1, 24 teeth were prepared by pumicing and acid etching with 37% phosphoric acid. In group 2, 24 teeth were prepared with a 1/4-round bur in a low-speed handpiece and then acid etched. In group 3, 24 teeth were prepared by high-speed (160 PSI) microabrasion using 50 mu alpha alumina particles in a KCP 2000 machine. In each group, 12 teeth were sealed with a filled sealant and 12 teeth with an unfilled sealant. All the teeth were stored in artificial saliva for 7 days and thermocycled for 2000 cycles. Teeth were then sealed apically and coated with nail varnish 1 mm from the margins and stained in 1% methylene blue for 24 h. Each tooth was sectioned in three locations and ranked (0-3) for microleakage. RESULTS There were 216 sections and 66% showed no leakage. CONCLUSIONS Chi-square statistical analysis of the data led to the following conclusions: 1) superior results were obtained when the tooth surfaces were prepared by a bur, 2) conventionally and KCP 2000-prepared tooth surfaces yielded similar results, and 3) the unfilled sealant was superior to the filled sealant.