Flexural strength of provisional restorative materials

A provisional restorative material must be strong enough to resist fracture during function. This study tested five autopolymerizing provisional resin materials under conditions that related the stresses acting on them to those acting on a fixed partial denture. The highest values for fracture resistance were displayed by Snap poly(ethyl methacrylate) material. However, two of the 11 samples of this material displayed markedly lower values for fracture resistance. This finding warrants further investigation, because inconsistency had clinical implications. In decreasing order, the fracture resistance of the other materials was as follows: the poly(methyl methacrylate) materials, Caulk temporary bridge resin and G-C Unifast temporary resin; the composite material, Protemp; and the epimine material, Scutan.