A STUDY ON MICROLEAKAGE AFTER RESIN FILLING OF CLASS-V CAVITIES PREPARED BY ER-YAG LASER

Objective: The aims of this study were to investigate microleakage aft er composite resin filling to class V cavities prepared by Er:YAG lase r and to compare the results with those obtained by a conventional met hod 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 teet h were used in this study. Teeth were divided into three groups of six teen each and class V cavities of the same size were prepared by Er:YA G 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 w ere treated with 30% phosphoric acid, After the cavities were filled w ith the composite resin, the teeth except the areas of cavities and ma rgins were covered by nail varnish and dye penetration was performed u nder 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 mere eva luated by stereoscopy and scanning electron microscopy (SEM). Results: Microleakage at the cavity margins was observed in all three groups u sing the dye penetration method, but there was no significant differen ce among the three groups. SEM results showed similar results with the dye penetration method. Conclusion: These results suggest that microl eakage at the cavities prepared by Er:YAG laser is at the same level a s for prepared by air turbine using dye penetration and SEM methods.