Avaliação da infiltração marginal após clareamento dental e restauração com resina composta, variando o sistema adesivo

The purpose of this study was to evaluate microleakage in composite resin restorations, with different adhesive sys- tems, after bleaching. Class V cavities were made in vesti- bular and lingual surfaces of 15 human premolars. A so- dium perborate and water mixture was applied to all cavi- ties, which were sealed with glass ionomer cement. The bleaching agent was replaced twice, at four-day intervals; next, cavities were neutralized with calcium hydroxide pas- te. Restorations were made with composite resin, but with different adhesive systems: on vestibular cavities, conditi- oning was carried out with 37% phosphoric acid followed by a conventional adhesive system; on lingual cavities, a self-etching primer/adhesive was used. Teeth were sealed (except one millimeter of restoration margins), immersed in Rodamine B, and prepared for stereomicroscopy analy- sis. Samples were classified according to marginal infil- tration scores, and the Mann Whitney test (p<0,05) was applied to the data. No significant statistical differences were detected between the two experimental conditions which were evaluated. We concluded that the adhesive sys- tem (4th or 5th generation) does not affect the restoration sealing after bleaching.