Improving fissure sealant quality: mechanical preparation and filling level

Objective: To assess the effect of different modes of fissure preparation a nd filling level on the quality of pits and fissure sealants. Methods: Various modes of fissure preparation in combination with two filli ng levels were examined. A total of 90 caries-free extracted human molar te eth were divided into three groups according to fissure preparation: (a) no mechanical preparation; (b) mechanical preparation with a round carbide bu r; and (c) mechanical preparation with a tapered fissure diamond bur. All f issures were acid-etched and each group was subdivided according to filling level, either to the border or overfilled, using Helioseal (Vivadent, Scha an, Lichtenstein) as a sealant material. A modified microleakage assay was performed, combining occlusal loading and thermocycling, prior to staining with 0.5% Basic Fuchsin. After sectioning, teeth were examined and photogra phed in a reflected light microscope, sealant retention was observed and re corded. Microleakage and sealant penetration depths were measured for each section. Two-way ANOVA was used for statistical analysis. Results: Sealant penetration and retention were significantly improved by m echanical preparation compared to non-prepared fissures (p < 0.0001), and p reparation with a tapered fissure diamond bur was superior to the round car bide bur. Overfilled fissures caused significantly higher levels of microle akage (p < 0.004). Conclusions: Based on the results of this in vitro study, it is suggested t hat fissure sealant quality may be improved by mechanical preparation, pref erably with a tapered diamond bur, and filling just to the border. Overfill ing of fissures should be avoided. (C) 2000 Elsevier Science Ltd. All right s reserved.