Influence of Organic and Synthetic hydroxyapatite on Selected Properties of Denture Base Materials

Background and Objectives The common prosthetic resin material, polymethylmethacrylate (PMMA), has the disadvantages of surface roughness. Heat-cured PMMA resin has the added disadvantage of lacking strength. The aims of the study were to investigate the difference between the addition of 5% natural micro-hydroxyapatite procured from eggshells, compared to the addition of the same amount of synthetic micro-hydroxyapatite particles sized at 52 Materials and Methods Thirty disc-shaped samples were divided into three groups as follows: control (Group A), 5% synthetic HA (Group B), and 5% natural HA (Group C). We fabricated the samples by standard methods. We measured Ra and hardness values by a surface profilometer and a Shore D hardness tester, respectively. statistical analysis were performed by one-way ANOVA and post-ANOVA tests. Results The result showed agnatically smoother surface (Ra = 0.706 µm) and return Value higher hardness (81.1 Shore D) for organic HA when compared to the control group (Ra = 1.050 µm and hardness of 76.3 Shore D). In the synthetic HA group, hardness (79.5 Shore D) was higher whereas roughness (Ra = 1.106 µm) was not significantly different when compared to the control group. Conclusions Natural HA from eggshell surfaces significantly enhances the smoothness and hardness of PMMA compared to synthetic HA. The present material appears to be a promising green additive for improving the denture base.