scanning electron microscope (sem) evaluation of composite surface irradiated by different powers of er:yag laser

introduction: the aim of this study was to evaluate the composite surface treated by different powers of erbium-doped yttrium aluminum garnet (er:yag) laser in comparison with bur preparation via scanning electron microscope. methods: fourteen composite resin blocks with 15× 10 × 10 mm dimensions were used in this study. the samples were divided to seven groups as follow: group 1 (power: 1 w, energy: 50 mj); group 2 (power: 2 w, energy: 100 mj); group 3 (power: 3w, energy: 150 mj); group 4 (power: 4 w, energy: 200 mj); group 5 (power: 5w, energy: 250 mj); group 6 (power: 6 w, energy: 300 mj); group 7: diamond bur. then, the samples were prepared for sem examination. results : the surface treated by er:yag laser showed irregular and micro porous surface. conclusion: it seems that composite surface treatment by er:yag laser can be an alternative method for composite repair if suitable parameters are used.