Evaluation of the Effect of Titanium Dioxide and Silicon Dioxide Nanoparticles on Impact Strength of Two Commercially Available Heat Cure Acrylic Resins

Abstract

Introduction: Poor mechanical properties are among the main limitations of denture base resin. There has been a continuous attempt to improve the mechanical properties of denture base resins. Nanotechnology has evolved health care industry to a large scale and its applications are a boon to modern medicine and dental science. Nanoparticles are nowadays, extensively used in prosthodontics as they are incorporated in Polymethyl Methacrylate denture bases to alter the properties such as impact strength. Aim: To evaluate and compare the effect of titanium dioxide and silicon dioxide nanoparticles on impact strength of two commercially available heat cure acrylic resins. Materials and Methods: The in-vitro study was conducted in Department of Prosthodontics and Crown and Bridge, School of Dental Sciences, Sharda University Faridabad, Haryana, India between April 2019 to May 2021, that involved 120 samples. Materials compared were Dental Products of India (DPI) heat cure acrylic and Trevalon heat cure acrylic. Each group was further categorized into four groups to measure the impact strength i.e, without incorporation of nanoparticles and with incorporation of nanoparticles SiO2 and TiO2 and a combination of both. Samples obtained were tested for impact strength using Izod method. Statistical analysis was done using a one-way Analysis of Variance (ANOVA), Student’s t-test and Post-hoc Bonferroni test. Results: In the two types of materials studied, the mean impact strength of Trevalon was statistically significantly higher (p-value= 0.045) than DPI. After the addition of nanoparticles, i.e; SiO2 and TiO2 the mean impact strength was higher in Trevalon (8.66 kJ/m2 without the addition of nanoparticles, 5.79 kJ/m2 addition of 1% TiO2 nanoparticles, 5.77 kJ/m2 addition of 1% SiO2 nanoparticles and 5.75 kJ/m2 when a 1% combination of both the above was added) than DPI (7.19 kJ/m2 without the addition of nanoparticles, 5.86 kJ/m2 - addition of 1% TiO2 nanoparticles, 5.77 kJ/m2 addition of 1% SiO2 nanoparticles and 5.66 kJ/m2 when a 1% combination of both the above was incorporated). Conclusion: Mean Impact strength of Trevalon was higher than mean impact strength of DPI. Incorporation of TiO2 , SiO2 Nanoparticles or in combination decreases impact strength of both the commercially available heat cure denture base resin with statistically no significant difference.