Pengaruh Penambahan Nanosilika Abu Cangkang Kelapa Sawit pada Basis Gigi Tiruan Resin Akrilik Polimerisasi Panas terhadap Kekerasan Permukaan dan Kekuatan Impak

Abstract

The denture base is the part of the denture that rests on the soft tissues of the oral cavity and where the tooth elements are attached. Heat-cured Acrylic Resin is often used to make denture bases, but heat-cured Acrylic Resin has disadvantages, especially in terms of strength and hardness. This can be overcome by adding palm kernel shell ash nanosilica reinforcement, where nanosilica has a smaller particle size and has better homogeneity than silica when mixed with acrylic polymers and monomers. This study aims to determine the effect of the addition of nanosilica palm kernel shell ash with a concentration of 5% and 6% in heat-cured acrylic resin denture bases on surface hardness and impact strength. The design of this research is laboratory experimental. This research was conducted by dividing the samples into three groups, namely A, B, and C with samples measuring 65×10×2.5±0.5 mm as many as 60 samples. Each group amounted to 10 samples with 30 samples tested using Vickers Hardness Tester and 30 samples tested using Charpy Impact Tester. The results were analyzed using the univariate test, One-way Anova test, and LSD test. The surface hardness test in group A is 15,36 ± 0,39 VHN, group B is 16,85 ± 0,27 VHN, and group C is 18,45 ± 0,41 VHN. The impact strength test in group A is 11,36 ± 1,64 J/mm2, group B is 5,61 ± 1,50 J/mm2, and group C is 4,82 ± 1,44 J/mm2. The results of the Kruskal-Wallis and one-way Anova test there was a significant effect in groups B and C on surface hardness and impact strength with a value of p = 0,0001 (p<0.05). Based on the Mann-Whitney test results, there is a significant difference in surface hardness between group A with group B and C have value of p =0,0001 (p<0.05), and group B and group C with p =0,0001 (p < 0.05). Based on the LSD test results, there is a significant difference in impact strength between group A with group B and C have value of p =0,0001 (p<0.05), and group B and group C with p =0,0001 (p < 0.05). In this study, it can be concluded that there is an effect of adding palm kernel shell ash nanosilica to RAPP denture bases that can increase surface hardness, but decrease impact strength. Therefore, palm kernel shell ash nanosilica can be used as a reinforcing material used for RAPP denture bases to make them more resistant to scratches and abrasion that occur in heat-cured, but less able to withstand sudden impacts, but the impact strength values obtained are still within ISO standards.