Evaluation of the Effect of Incorporation of Nano-fluorohydroxyapatite on Tensile Strength and Modulus of Elasticity of an Essix Plate

Abstract

Background: Nano-fluorohydroxyapatite (nano-FHA) is a caries preventive agent that is applied in many fields of dentistry and has the potential of being added to Essix retainers to create antibacterial properties. Objectives: The purpose of this study was to investigate the effect of nano-fluorohydroxyapatite addition on the tensile strength and modulus of elasticity of an Essix plate. Methods: The nano-fluorohydroxyapatite was synthesized and added to an Essix plate in various weight percentages: 0% (group1), 0.1% (group2) and 0.5% (group 3). We performed the measuring of flexural strength and modulus of elasticity for the experimented three groups using a universal testing machine. The data were analyzed through one-way ANOVA and Tukey’s test at the significance level of 0.05. Results: Accordingly, the obtained results were indicative of significant differences between the groups (P-value = 0.003); however, the difference between group 2 and control group was not statistically notable (P-value = 0.427). Furthermore, the tensile strength of group 3 significantly decreased (P-value = 0.04). In regards to the modulus of elasticity, the data were suggestive of significant differences between the groups (P-value = 0.002). Apparently, the modulus of elasticity of group 2 and group 3 decreased significantly compared to that of the control group (group 1). Conclusions: We can conclude that nano-FHA can be incorporated into Essix plates in concentrations of up to 0.1 wt% in order to create some caries preventing effects with no negative effects on tensile strength; however, adding nano-FHA to Essix plate will decrease modulus of elasticity.