Investigation of The Effects of The Ozonated Water and Sodium Hypochlorite on Dimensional Stability of Heat Cure Acrylic Resins Denture Base

Dimensional stability of removable dentures in various disinfecting agents is considered an important and necessary property. The purpose of this study is to evaluate the dimensional stability of two types of heat-cured acrylic after immersion in distilled water, ozonated water and sodium hypochlorite solution.

In this in-vitro study, 60 disk-shaped samples were made, including 30 samples of Acropars heat cure acrylic resin and 30 samples of Pro Base heat cure acrylic resin. 30 samples of each acrylic were divided into three subgroups (n=10): 1) Immersion for 8 hours in distilled water (control group). 2) immersion for 8 hours in 1% sodium hypochlorite and 3) immersion for 8 hours in ozonized water. After every 8 hours, the solutions were changed and all samples were placed in disinfectant solutions for 16 weeks. Before and after immersion in each of the environments, the diameter of the samples was measured with an accurate micrometer with an accuracy of 1 micron. Finally, the obtained data were analyzed through appropriate statistical tests.

Results showed that the dimensional changes of Pro Base heat cure acrylic resin by immersion in any of the 1% sodium hypochlorite solutions, ozonated water and, distilled water are not significant, and the dimensional changes of Acropars (Iranian) acrylic resin are not also significant in each of these solutions. Therefore, both disinfectant solutions are suitable for disinfection of dentures.

After 16 weeks of immersion, the change in dimensions of heat cure acrylic resins in ozonated water is clinically acceptable, and according to the confirmation of the appropriate disinfection property of ozonated water in previous research and further studies, it can be suggested to the patients as a suitable disinfectant for disinfection of dentures.