Effect of light cure intensity on shear bond strength and microhardness of pit and fissure sealant in permanent teeth

Abstract Purpose: To examine whether reducing the curing time when using lamps with high intensities affects the shear bond strength or the microhardness of pit and fissure sealants, as these parameters are predictive factors for sealant retention and hardness on teeth. Methods: The shear bond strength was measured on the fissure sealant adhesions performed on intact non-carious extracted permanent human molars. Each tooth was tested on three separate areas using different light-intensity curing lamps and time periods. The curing protocols were applied as follows: Group 1, 700mW/cm2 for 20 seconds; Group 2, 1400mW/cm2 for 10 seconds; and Group 3, 2000mW/cm2 for 3 seconds. The microhardness test was done on three groups of 20 fissure sealant sample molds each. Three measurements were conducted per sample. Results: There was no statistically significant difference in shear bond strength between the three groups (. There was a significant effect of light cure intensity on microhardness between all three groups (p <.001). Conclusion: The curing time of sealants in permanent teeth couldn't be shortened while increasing the intensity of the light without affecting their microhardness. However, it won't decrease the shear bond strength.