Distortions in Indexing as affected by two types of Self-polymerizing Acrylic Resin and Bar

The purpose of this study was to measure linear distortions (the vertical direction) and rotational distortions in indexing a three-unit fixed partial denture. The three-unit was assembled with the second premolar and molar as abutments and the first molar as a pontic on the left mandible. The two types of self-polymerizing acrylic resin (the Unifast, the Pattern Resin) and bar for reinforcing were used, and four types specimens (1. only the Unifast, 2. only the Pattern Resin, 3. the Unifast and bar, 4. the Pattern Resin and bar) were prepared. The following results were obtained. 1. The linear distortions and rotational distortions of specimens fixed with only the Unifast were smallest. 2. The standard deviation of the linear and rotational distortions of the specimens fixed with the Pattern Resin and bar was the smallest.