Flow characteristics and sealing ability of fissure sealants

This study evaluated the relationship between fissure sealant viscosity, le akage prevention and the incidence of void formation of five commercially a vailable pit-and-fissure sealants. Seventy-two intact, caries free human pr emolars and molars were divided into six test groups of 12 teeth each. All teeth were cleaned with a flour of pumice prophylaxis followed by etching f or 60 seconds with 37% H3PO4, rinsing for 30 seconds and drying with oil-fr ee air. Five commercial, light-cured fissure sealants and an unfilled versi on of one sealant were applied following manufacturers' instructions. Teeth were thermal cycled for 5000 cycles from 5-50 degrees C with a one-mi nute dwell time at each temperature. Silver nitrate staining followed by me siodistal sectioning was performed. Leakage and void formation were evaluat ed at X50 optical magnification. Viscosity was assessed by syringing the fissure sealants into short pipette s, allowing free flow for 30 seconds and then light curing for one minute. The length of unfilled capillary was measured with a Vernier gauge. All experimental data was subjected to a one-way ANOVA, and where differenc es were detected, they were identified by a post hoc Tukey hsd test at a pr iori alpha = 0.05. Based on the conditions of the study, viscosity and now characteristics had no effect on sealing ability or void formation.