Microleakage in conservative cavities varying the preparation method and surface treatment

Objective: to assess microleakage in conservative class v cavities prepared with aluminum-oxide air abrasion or turbine and restored with self-etching or etch-and-rinse adhesive systems. materials and methods: forty premolars were randomly assigned to 4 groups (i and ii: air abrasion; iii and iv: turbine) and class v cavities were prepared on the buccal surfaces. conditioning approaches were: groups i/iii - 37% phosphoric acid; groups ii/iv - self-priming etchant (tyrian-spe). cavities were restored with one step plus/filtek z250. after finishing,specimens were thermocycled,immersed in 50% silver nitrate,and serially sectioned. microleakage at the occlusal and cervical interfaces was measured in mm and calculated by a software. data were subjected to anova and tukey's test (α=0.05). results: marginal seal provided by air abrasion was similar to high-speed handpiece,except for group i. there was significant difference between enamel and dentin/cementum margins for to group i and ii: air abrasion. the etch-and-rinse adhesive system promoted a better marginal seal. at enamel and dentin/cementum margins,the highest microleakage values were found in cavities treated with the self-etching adhesive system. at dentin/cementum margins,high-speed handpiece preparations associated with etch-and-rinse system provided the least dye penetration. conclusion: marginal seal of cavities prepared with aluminum-oxide air abrasion was different from that of conventionally prepared cavities,and the etch-and-rinse system promoted higher marginal seal at both enamel and dentin margins.