Objective: The aims of this study were to investigate microleakage after composite resin filling to class V cavities prepared by Er:YAG laser and to compare the results with those obtained by a conventional method using an air turbine in vitro.
Summary background data: There has been no report of the microleakage study on class V cavities prepared by Er:YAG laser.
Methods: Forty-eight human extracted single root teeth were used in this study. Teeth were divided into three groups of sixteen each and class V cavities of the same size were prepared by Er:YAG laser for two groups and by air turbine for one group (control). For one group prepared by Er:YAG laser and the control group, the teeth were treated with 30% phosphoric acid. After the cavities were filled with the composite resin, the teeth except the areas of cavities and margins were covered by nail varnish and dye penetration was performed under the 0.6% Rhodamine B at 36 degrees C for 48 hrs. The teeth were sectioned at a thickness of 2 mm transversally and the slices were evaluated by stereoscopy and scanning electron microscopy (SEM).
Results: Microleakage at the cavity margins was observed in all three groups using the dye penetration method, but there was no significant difference among the three groups. SEM results showed similar results with the dye penetration method.
Conclusion: These results suggest that microleakage at the cavities prepared by Er:YAG laser is at the same level as for prepared by air turbine using dye penetration and SEM methods.