The Effect of using Iraqi Plaster with Type III Dental Stone as Investing Materials on the Vertical Dimension of Occlusion in Acrylic Resin Complete Dentures (A comparative Study)

Abstract

Aim of study: The aim of this study was to evaluate the Iraqi plaster when used as investing material and studies its effect on the changes of vertical dimension of occlusion of heat cured acrylic resin complete dentures using four different investing methods in compression molding technique.Materials and methods: Forty acrylic resin complete dentures were prepared from heat-cure acrylic resin denture base. The study include 4 groups depending on the type of investing method, Group 1: plaster- stone- mixed, Group 2: plaster- stone- plaster, Group 3: plaster- mixed- mixed, Group 4: plaster- mixed - stone. Each group of them contains 10 dentures. Changes in occlusal vertical dimension were measured before and after denture processing. Collected data were analyzed with analysis of variance and Tukey's test at 95% level of confidence (p=0.05).Results: The mean of changes in dimension of occlusion in different groups were: group1: (0.6337mm), group2: (0.6253mm group3: (1.0171mm), and group4: (0.9837mm).Conclusion: Less dimensional changes was observed in the group of dentures that invested with plaster-stone- plaster when compare with other investing methods.

Keywords: Iraqi plaster, stone, flasking, vertical dimension of occlusion.