Pengaruh Penambahan Silika Kulit Edamame (Glycine max (L.) Merr.) terhadap Kekuatan Tarik Resin Akrilik Heat Cured

Abstract

Introduction: Heat-cured acrylic resin is widely used as a denture base material because of its favorable esthetics, biocompatibility, ease of manipulation, and affordability. However, its relatively low tensile strength remains a major limitation, increasing the risk of fracture during clinical use. The addition of reinforcing fillers such as silica has been reported to improve the mechanical properties of acrylic resin. Edamame peel (Glycine max (L.) Merr.), an abundant agricultural waste in Indonesia, contains natural silica and has potential as an environmentally friendly reinforcing material. Objective: This study aimed to evaluate the effect of edamame peel silica addition on the tensile strength of heat- cured acrylic resin and to determine the most effective concentration. Methods: This experimental laboratory study employed a post-test only control group design. Twenty-four specimens were divided into four groups (n = 6): a control group without silica addition and three treatment groups with 3%, 5%, and 7% edamame peel silica added to the acrylic resin powder. Silica was extracted from edamame peel through combustion, alkalinization, precipitation, drying, and sieving processes. Tensile strength was measured using a Universal Testing Machine. Data were analyzed using the Shapiro–Wilk test, Levene’s test, One-Way ANOVA, and Least Significant Difference (LSD) test. Results: The results showed a tendency toward increased tensile strength in the groups with silica addition compared to the control group, particularly at concentrations of 3% and 5%. However, statistical analysis revealed no significant differences among the groups (p > 0.05). Conclusion: The addition of edamame peel silica to heat-cured acrylic resin tends to increase tensile strength, although the improvement was not statistically significant. Edamame peel silica has potential as a natural reinforcing filler; however, further studies are needed to optimize particle size, dispersion homogeneity, and surface modification to achieve a significant enhancement in mechanical properties. Keywords: heat-cured acrylic resin, tensile strength, silica, edamame peel, denture base.