Evaluation of Hardness, Impact, and Transverse Strength Tests of Heat-Cured Acrylic Denture Base Material Following the Addition of Watercress, Tea Tree, and Clove Oils: An In Vitro Study

Introduction: This study evaluated the hardness, impact, and transverse strength of heat-cured acrylic resin modified with natural oils, including watercress, tea tree, and clove oils, at different concentrations. Methods : Specimens for surface hardness transverse, and impact strength tests were fabricated using the acrylic resin with or without adding natural oils, including watercress, tea tree, and clove oils, at concentrations of 2.5%, 5%, and 7.5% by volume of monomer. Mechanical tests were conducted using an impact testing device and a universal Instron testing machine. Results : The addition of watercress oil could not significantly increase or decrease hardness, impact, and transverse strength ( P > 0.05). The addition of tea tree oil decreased hardness and transverse strength significantly at a concentration of 0.075 ( P < 0.001). The addition of clove oil significantly increases impact ( P = 0.012) and transverse strength ( P < 0.001) at a concentration of 0.075. Conclusion : The addition of clove oil at a concentration of 7.5% by volume of monomer can enhance the impact and transverse strength of heat-cured acrylic resin.