Effect of acid challenge on the surface properties of external and internal layers of cross-linked acrylic teeth

Abstract Introduction Artificial acrylic teeth must be resistant to acids for ensure the maintenance of their properties throughout their useful life. However, there are no studies available in the literature about the surface properties of hardness and roughness of the different layers of acrylic resin that make up the artificial teeth submitted to simulated erosion tests. Objective To evaluate the surface hardness and roughness of external and internal layers of artificial cross-linked acrylic teeth submitted to acid challenge. Methodology First molars (SR Postaris and Trilux) transversely sectioned had its Vickers hardness and roughness initially evaluated. These tests were repeated after half of the tooth samples (n=10) be immersed into distilled water (control) and half in vinegar during 15 min/day for 28 days. Data were analyzed using 2-way ANOVA and Tukey's test (α=0.05). Result The initial external layers hardness of both was not significantly altered by acid challenge (p> 0.05) and the immersion in vinegar caused no deleterious effect on the initial internal layers hardness of the two tested teeth (p>0.05). After 28 days, the initial roughness of both teeth evaluated for the two layers was not affected by water or vinegar (p>0.05). Conclusion The reinforced acrylic teeth were resistant to acid challenge since its internal and external layers showed no significant change in hardness and surface roughness.