Effects of Cooling Shrimkage and Reheating of Impressions -Reproducibility of Stone Models Simulated Full Crown Preparation with Adjacent Teeth-

Abstract

The effect of cooling shrinkage and reheating of rubber impressions on the reproducibility of stone models were evaluated. The models were prepared using an epoxy resin mold to simulate a full crown preparation with adjacent teeth. The models were measured using a three-dimensional measuring system. Impressions made at oral temperature during setting were reheated in water at oral temperature, and the effects of reheating on the reproducibility of models were investigated. 1. Models obtained from rubber impressions set at oral temperature showed dimensional change and deformation due to cooling shrinkage of the impression. 2. Reheating of the impression improved the reproducibility of models. 3. An immersion time of 5 to 30 minutes was acceptable for reheating the impression in water at oral temperature.