The effect of composite resin contamination by latex gloves with and without powder on the shear bond strength to dentine in bovine tooth

Abstract

Latex glove contamination of composite resin is a usual clinical problem during restorative dental treatment that may affect the shear bond strength of adhesives to dentin. Purpose: The aim of this study was to investigate the effect of composite resin contamination by powdered and non-powdered latex gloves on the shear bond strength of Clearfil SE Bond (sixth generation) and Single Bond (fifth generation) to composite resin. Materials & Methods: In this study 120 bovine incisor teeth were selected. The facial surface of teeth were ground until the superficial dentin was exposed and then samples were embedded in self cure acrylic molds, and surface of samples were smoothened with 400 & 600 grit silicon carbide paper. Specimens were randomly divided into two groups of 60 teeth based on type of adhesive agent (Single Bond, Clearfil SE Bond) and each group randomly divided into three subgroups of 20 teeth based on composite contamination. Specimens in subgroups were prepared as follows: 1) Control-without contamination 2) Contamination with powdered latex glove 3) Contamination with non-powdered latex glove. Then composite were bonded on specimens via plastic mold. Subsequent to thermocycling (500 cycles between 5C2C and 55C2C), shear bond strength was measured by Hounsfield Test Equipment H5K-S model using knife edge crosshead. The surface area was 0/5cm?? and the speed of exerted force was 0/5 mm/min. Two-way ANOVA test was used to compare shear bond strength of different groups regarding to bonding agent type and contamination type, and Tukey test was used for two by two comparisons of the groups. One-way ANOVA test was used to compare shear bond strength in each bonding agent group. Result: The mean of shear bond strength was not statistically significant regarding to bonding agent type F (1,114) =0/64 (P=0/42); however, contamination significantly affect the shear bond strength (P=0/001) .On the other hand, interaction between bonding agent type and contamination was not significant. Conclusion: Latex glove contamination may decrease shear bond strength of composite to dentin. In this study in Clearfil SE Bond system contamination with powdered latex glove significantly decreased shear bond strength to dentin. In Single Bond group there was no significant difference between subgroups.