RESUMO
PURPOSE: To compare the influence of in vivo and in vitro conditions on marginal and internal adaptation of composite restorations using three adhesive systems. METHODS: 60 human teeth were distributed among three material groups. In each root, three Class V cavities were prepared and filled with the same material, one in vivo and, after extraction, one in perfused and one in not-perfused dentin specimens. RESULTS: Evaluation of gap formation at the composite/dentin interface with SEM revealed no significant differences between marginal and internal adaptation. Adaptation data were different according to the materials used (P = 0.002), and to experimental conditions (P = 0.04). According to the gap frequency concerning experimental conditions, it was concluded that in vivo adaptation of composite restorations to dentin seemed to be better compared to in vitro results achieved with perfused dentin, and worse compared to in vitro results achieved without perfused dentin. Additionally, it was noted that the impact of the experimental conditions on the performance of different adhesive materials was dependent on the composition of the materials. Least adaptation was found for the perfused specimens in most groups, and least gap formation for the non-perfused in vitro specimens. A material dependent influence of experimental conditions on the study influenced the results. In vitro adaptation to perfused dentin seems to be undervalued compared to the clinical situation in certain circumstances.
