Accuracy of the acrylic resin pattern for the implant-retained prosthesis

An in vitro study was conducted to determine the accuracy of fit of the acrylic resin pattern for the implant-supported prosthesis to the implant abutments. A master model containing five Nobelpharma titanium implants was fabricated using Ivocap acrylic resin. Using this model, five standardized acrylic resin patterns were fabricated from the three test dental acrylic resins. The fabricated patterns remained on the master model for 24 hours before removal and subsequent measurement. To compute the accuracy of each pattern, three special measuring points were firmly attached to each gold cylinder prior to pattern fabrication and the x, y, and z coordinates of these measuring points were determined. Measurements were made prior to pattern fabrication, with the cylinders on their respective abutments and after pattern fabrication, when the pattern had been removed from the master model. The results of this study showed that there was a significant difference in accuracy between the test acrylic resins and that none of these materials was completely accurate.