Flexural strength and superficial roughness of acrylic resins used for confection of occlusal splints

Abstract

The purpose of this work was to evaluate in vitro the addition effect of glass fibers in the flexural strength and surface roughness of resins used to make occlusal splints. For this study the flowing resins were used with different polymerization type: acrylic resin self-curing Vipi FlashTM (SR), conventional heat-cured Vipi CrilTM (HR) and microwave-cured Vipi WaveTM (MR), with and without addition of glass fibers (GF). Assumptions under study: the addition of fiber glass increases the flexural strength and the surface roughness of the specimens of evidence. Twelve samples were made (n = 12) for each group, from a metallic die with 67 mm long x 12.60 mm wide x 3.00 mm thickness. The samples were subjected to the test of flexural resistance in universal test machine (EMIC DL 2000TM) with speed of 5 mm/min and to the test of RS in roughness (MitutoyoTM). The data were subjected to the analysis of variance and Tukey’s test (p < 0,01). Regarding flexural strength (MPa), difference was statistically significant for the polymerization type factor of resins only (SR = 81.54 ± 4.94, HR = 92.86 ± 16.85, MR = 86.24 ± 8.89). Regarding the surface roughness (RA-mm), there was a difference for the two factors evaluated: the polymerization type (SR = 0.10 ± 0.02, HR = 0.13 ± 0.03, MR = 0.11 ± 0, 13) and the addition of glass fibers (WF = 0.13 ± 0.02, NF = 0.10 ± 0.11). We can conclude that the addition of the glass fiber into the acrylic resin did not change the values of flexural strength. On the other hand, increased the value of surface roughness of the samples tested.