Inverse relationship between tensile bond strength and dimensions of bonded area.

It is a known fact that there is a relationship between magnitude of bonded area and laboratory tensile test results. This relationship has been described for a range of areas between 1 and 10 mm(2), in extracted, nonperfused teeth. The aim of this study is to test this relationship in perfused teeth, with bonded areas ranging from 0.7 to 110.9 mm(2). Dentin of 92 sound third human molars was exposed and perfused, and three groups of bonded areas (BA) were delimited: small (0.69-1.89 mm(2)), medium (8.66-19.54 mm(2)), and large (58.91-110.86 mm(2)). Tensile bond strength (TBS) of three adhesive restorative systems was found. The best nonlinear curve estimation was searched (SPSS 9.0) between TBS and BA, for each and all materials. The best estimation was, for all materials, TBS = 4.17 + 10.35/BA (p < 0.0001).