Evaluation of Elastic Modulus of Different Resins for Bone Simulation

Objectives: The aim of this study was to measure the elastic modulus of a polystyrene resin and two acrylic resins for bone simulation during mechanical tests. Methods: Ten cylindrical specimens with 15mm in height and 1mm in diameter were fabricated for each group: Group P – polystyrene resin (Piraglass, Piracicaba, SP, Brazil), Group C – acrylic resin Classico (Classico, Sao Paulo, SP, Brazil), and group V – acrylic resin Vipi (Vipi, Pirassununga, SP, Brazil). The materials were manipulated according to the manufacturers` instructions. Each specimen was submitted to a compression test in the universal testing machine EMIC DL3000 (EMIC, Sao Jose dos Pinhais, PR, Brazil) with a 5000-kgf load cell at crosshead speed of 2000mm/min. The elastic modulus was defined as the ratio of the applied stress to the resulting deformation within the elastic limit of each material. Data were submitted to one-way ANOVA and Fisher's test at 5% level of significance. Results: The group C presented the highest mean of elastic modulus (1.066±0.127GPa) followed by the groups V (1.030±0.1GPa) and P (0.026±0.009GPa). ANOVA revealed statistically significant difference among the groups (P<0.0001). Fisher's test showed significant difference between the group P and the groups C (P<0.0001) and V (P<0.0001). However, there was no significant difference between the groups C and V (P=0.3988). Conclusion: The polystyrene resin was not suitable to simulate bone tissue for mechanical tests. The acrylic resins presented elastic modulus values similar to the trabecular bone type III.