EFFECT OF ELECTRON BEAM RADIATION ON SHEAR BOND STRENGTH OF ORTHODONTIC BONDING ADHESIVES

Background and Aim: The goal of research developments in adhesive materials has been to achieve good and optimal bond strength during treatment and also enabling easy debonding and clean up procedures at the end of the treatment. Hence this study was designed to evaluate, the effect of exposure to electron beam radiation on shear bond strength of two commonly used adhesives in Orthodontics. Materials and methods: Lightcure composite and self cure adhesive was used for the purpose. 200 upper 1 st premolars extracted for orthodontic purpose was selected .In each group, upper 1st premolar; SS brackets were bonded with corresponding adhesive systems. The bonded specimens were subdivided into five groups for evaluation of bond strength before and after irradiation with 2kGy, 4kGy, 8kGy and 10kGy. The shear bond strength of the bonded specimens was tested using Universal Testing Machine. The data obtained was statistically evaluated using One- Way ANOVA. Results: When comparing before and after irradiation, the light cure adhesive had the shear bond strength significantly increased after irradiation with 4kGy and in Self cure adhesive the shear bond strength after irradiation significantly decreases. Conclusion: The electron beam irradiation had negative effect on the shear bond strength of self cure and light cure orthodontic adhesive; except for the radiation dose of 4kGy in case of light cure adhesive.