Assessment of Tooth Preparation via Er: YAG Laser and Bur on Microleakage of Dentin Adhesives

Objective: microleakage can be responsible for tooth hypersensitivity, secondary ca-ries, and the possibility of pathological pulp alterations in restored teeth.recently, al-ternative methods for tooth preparation such as laser irradiation have been studied; but there are limited studies on primary teeth. the aim of this in vitro study was to com-pare the degree of microleakage of composite restorations prepared by er:yag laser and conventional bur preparation with two adhesive systems in primary teeth.materials and methods: eighty primary canine teeth were randomly divided into 4 groups. class v cavities were prepared by er:yag laser or diamond bur on buccal surface. the groups were as follows: group1: high speed drill + self-etching adhesive adper prompt-l-pop, group 2: er:yag laser + etch & rinse adhesive adper single bond, group 3: high speed drill + adper single bond, group 4: er:yag laser + ad-per prompt-l-pop. cavities were restored with filtek z250 composite resin. then all of the specimens were polished, thermocycled, immersed in 2% methylene blue solu-tion and sectioned longitudinally. degree of microleakage was evaluated by two eva-luators who assigned the micrleakage score (0 to 3). the original data were analyzed by the kruskal-wallis and dunn’s tests.results: there were significant differences between bur-prepared cavities in the ad-per single bond and other groups. there were no statistically significant differences between other groups.conclusion: laser-prepared cavities showed higher microleakage scores than cavities prepared with diamond bur with etch and rinse adhesive system. no significant differ-ence was revealed between the laser and bur-prepared cavities using self-etch primers.