A Comparative Study on the Effect of Two Different Investing Mediums on the Movement of Artificial Teeth during the Fabrication of Complete Denture: An in vitro Study

Abstract

Acrylic processing of waxed-up dentures is considered to be a crucial and technique-sensitive procedure. Even after investing a lot of time and clinical skill a definitive movement of teeth during and after processing has long been observed which lead to occlusal discrepancies and disturb the harmonious occlusal scheme achieved earlier. Shifting of the teeth can occur as a result of the investing procedures and investing materials. The objective of this study was to evaluate and compare the movement of artificial teeth in two-dimensions of space (anteroposterior and mediolateral) during processing of the waxed-up dentures using two different gypsum materials for investing. Methods: Two groups of 15 waxed-up maxillary dentures were processed using two different investing mediums (a) dental plaster and (b) combination of dental stone core and plaster mold. The artificial teeth movement was measured in the mediolateral and the anteroposterior directions between predetermined reference points before and after processing with the aid of a traveling microscope. The findings were statistically analyzed using parametric t-tests and ANOVA F-test. Results: Artificial teeth movement in both the anteroposterior and mediolateral direction was less with the use of investment combination of dental stone core and plaster mold when compared to the conventional method of investing with dental plaster. Conclusion: The dental stone core method is superior in view of the fact that it produces significantly less artificial teeth movement than the conventional method. However, neither of the investing methods is successful in completely preventing artificial teeth movement.

Effect of using teeth positioning guides on the accuracy of CAD/CAM complete dentures: an in-vitro study

“…Studies found that there is still no certain technique whether a conventional or CAD/CAM that can entirely eliminate denture teeth movement. (9,10) Materials and methods -This in-vitro study was applied on an educational maxillary edentulous model made of dental stone.…”