Comparison of shear bond strengths with different bevel preparations for the reattachment of fractured fragments of maxillary central incisors

Abstract

Fractures of anterior teeth are a highly prevalent form of dental trauma. Among the various treatment options, reattachment of the fractured part to the remaining tooth has a lot of advantages. The aim of this study was to compare different bevel preparation techniques when reattaching fractured fragments to maxillary central incisors. This study was performed on 52 maxillary central incisors that were randomly divided into 3 experimental groups and 1 control group. In the control group, the repair was done by attaching the fractured fragment using bonding and composite resin without any bevel preparation. In the second and third groups, the bevel preparation was done to a depth of 0.5mm before attachment of the fragment on the palatal side of the fracture and on the labial and palatal sides, respectively. In the fourth group, after tooth preparation, a 0.5mm composite veneer was placed on the labial surface. The amount of force needed to refracture the tooth was measured with a universal testing machine, and shear bond strength was calculated in MPa. The mean and standard deviation (mean±SD) of shear bond strengths in the control group were 81.48±8.18MPa. In the palatal bevel group, they were 97.74±11.41MPa; in the labial and palatal bevel group, 131.56±9.25MPa; and in the composite veneer group, 104.36±5.50MPa. Significant differences were observed between the groups, but there was no significant difference between the palatal bevel and composite veneer groups. Reattachment of the fractured fragments by all three methods increased the shear bond strength. The highest shear bond strength was obtained when both labial and palatal bevels were used.