The purpose of the present study was to evaluate the cytotoxicity of two different dentin-bonding agents on cell cultures. NIH-3T3 fibroblasts were plated in Petri dishes. After 48 hours, when the cells were in confluence, "primers" and adhesives of two dentin bonding systems (Scotchbond Multipurpose Plus and Clearfil Liner Bond 2) were applied on glass slides, which were placed in the dishes. Composite resin and calcium hydroxide were also used. Polymerization, when required, was performed with a XL 1500 light unit. No material was used in the control group. All materials remained in contact with the cells for 24 hours, except for phosphoric acid, which was maintained for 20 seconds. After that, cells were counted in a hemocytometer and cell viability was obtained by tripan blue dye exclusion. The data were submitted to statistical analysis (ANOVA and Tukey's test). It was possible to conclude that all materials tested presented lower cell viability than the control group, except calcium hydroxide. Composite resin and phosphoric acid application caused similar viability rates as calcium hydroxide. "Primers" plus adhesive application of both adhesive systems produced similar cytotoxicicity, both causing smaller cell viability than that of calcium hydroxide group. No differences were found in relation to the cytotoxic effects of the components in both adhesive systems.
Dentin-bonding agents; Biocompatibility; Cell culture; Cytotoxicity; Composite resins
