Acrylic resins had been used to manufacture the removable complete dentures bases for many years. However there are many disadvantages connected to the use of this material as a denture base, the reason that makes the researches use metal bases as replacement, there are many ways to make patterns for metal casting in partial and complete dentures,
Purpose: The purpose of this study is to compare the fit accuracy of Co-Cr metal denture bases casted from conventionally waxed patterns to other Co-Cr metal denture bases casted from CAD-CAM milled wax patterns.
Materials and Methods: Using 20 replicated master casts obtained by duplicating a metal die representing a fully edentulous maxillary arch, 10 Co-Cr metal plates were casted from conventionally waxed up patterns, and another 10 Co-Cr metal plates were casted from CAD-CAM milled wax patterns, after artificial teeth setting, acrylic resin had been processed, to simulate an ordinary denture base. After applying injectable addition silicone super light body impression material between each denture base and metal die was performed and let it set under 5kg weight designed to be used in this experiment, weighing process of the elastomeric silicone layer was performed to compare adaptation of the two groups of dentures.
Results: The values of the silicone layer weight (in grams) in the conventional waxing group was smaller than the values of the silicone layer weight in the Co-Cr metal plates were casted from CAD-CAM milled wax patterns.
Conclusions: Dentures with Co-Cr metal plates casted from conventionally waxed up patterns fits more accurately than the dentures with Co-Cr metal plates casted from CAD-CAM milled wax patterns.