Influência da marca do condicionador ácido na resistência de uni？o da resina composta à dentina

introduction: despite the importance of the acid etching step on bonding procedures, little is known about the acid etchant brand effect on bond strength of adhesive to dentin. objective: the aim of this study was to evaluate the effect of different acid etchants at the bond strength of composite resin to dentine. material and method: twenty five bovine incisors had their crown sectioned in two hemi-sections. the buccal surfaces were grounded with #180 silicon carbide (sic) abrasive paper to exposure of dentin, followed by #600 sic paper to standardize the smear layer. the samples were randomly allocated into five groups (n = 10) according to acid etchant brands: 3m espe, ultradent, dentsply, villevie and dfl.only a two-step etch-and-rinse adhesive system (ambar, fgm) was used. silicon molds were used to build-up three resin composite cylinder per sample. after 24 hours, cylinders were submitted to shear load until the failure. data were analyzed by one way anova and tukey`s test (a = 0.05). the failure mode was evaluated under optical microscopy and the data were submitted to chi-square test (a = 0.05). result: there was no statistical difference on bond strength obtained between the acid etchants evaluated. there was predominance of adhesive failures, except for etchants of dentsply and dfl that showed similarity between mixed and adhesive failures. conclusion: different brands of acid etchants did not influence on the bond strength of composite resin to dentin.