Test de mecánicas comparativas para 3 diferentes materiales de alineadores ortodóncicos en diferentes tiempos; estudio in vitro

Abstract

OBJECTIVES: To evaluate the physical and mechanical properties of 3 different thermoplastic materials based on polyethylene terephthalate glycol (PET-G), for the manufacture of orthodontic aligners; Track A, Memory Track and Claris, in delivery status, thermoformed, thermoformed and thermocycled at 7 and 14 days. METHODS: In this experimental study, 432 samples of thermoplastic materials (PET-G) were prepared, they were divided into 4 groups: Supply state (C), Thermoformed (T), Thermoformed and thermocycled at 7 days (TT7), Thermoformed and thermocycled at 14 days (TT7). Thermoforming was done through 3D printed molds and thermocycling was done through 100 cycles and 200 cycles. The mechanical and physical properties were evaluated. Shapiro-Wilk, Anova with Welch correction, Games-Howell tests were performed for statistical analysis and the significance level was set at 0.05. RESULTS: In the 3 thermoplastic materials based on (PET-G) there was a reduction in the bending and tensile elasticity modulus after thermoforming; Track A (1,96-0,95Gpa), Memory Track (2,48-1,02Gpa), Claris (1,90-1,07Gpa), after thermoforming and thermocycling at 7 days; Track A (1,72-0,96Gpa), Memory Track (0,57-0,84Gpa), Claris (0,77-0,82Gpa), after thermoforming and thermocycling at 14 days; Track A (1,97-1,03Gpa), Memory Track (0,72-1,11Gpa), Claris (0,82-0,92Gpa). CONCLUSIONS: Thermoforming and thermocycling had an important role in reducing the mechanical and physical properties of the 3 materials based on polyethylene terephthalate glycol (PET-G), where the thermoplastic material Track A stood out, followed by Claris and then the Memory Track.