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

Objective: Microleakage can be responsible for tooth hypersensitivity, secondary car- ies, 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 + Adper Prompt-L-Pop. Cavities were restored with Filtek Z250 composite resin. Then all of the specimens were polished, thermocycled, immersed in 2% methylene blue solution and sectioned longitudinally. Degree of microleakage was evaluated by two evaluators who assigned the micrleakage score (0 to 3). The original data were ana- lyzed by the Kruskal-Wallis and Dunn’s tests. Results: There were significant differences between bur-prepared cavities in the Adper Single Bond and other groups. There were no statistically significant differ- ences 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.