Effect of Alkaline peroxide denture cleansers on surface roughness and hardness of Conventional heat cured and CAD/CAM denture base resins.

Abstract

Objectives: This study aimed to evaluate the changes of surface roughness and hardness of conventional heat-cured (CHC) and CAD/CAM PMMA after immersion in alkaline peroxide chemical denture cleansers (DC), simulating one -year of use.Materials and Methods: 30 specimens of CHC, and another 30 specimens of CAD/CAM PMMA were divided into three groups (n= 10), each were immersed in two commercially available alkaline peroxide DC (Corega tablets and Polident tablets) as well as distilled water (control group). The mean surface roughness (R a ) of the specimens was recorded using contact stylus surface analyzer device. The surface hardness (VHN) was recorded using Vickers micro-hardness tester. Ttest for paired observation and independent samples T-test were used to indicate and compare any changes in R a and hardness between the baseline and after simulated daily immersion in DC for one-year. Results:The tested DC had no significant effect on the R a and hardness of CAD/CAM PMMA specimens. But both types of DC produced significant increase in R a and significant decrease in VHN of the CHC PMMA specimens (P < 0.05). The R a of the CAD/CAM PMMA specimens was significantly lower and the VHN was significantly higher than that of the CHC PMMA after treatment with DC. Conclusions:Alkaline peroxide DC appears not to affect the R a and hardness of CAD/CAM PMMA. Alkaline peroxide DC produced negative effect on the R a and hardness of CHC PMMA. CAD/CAM denture base resins might be considered the material of choice to produce more durable dentures.