Evaluation of the fracture resistance of reattached incisal fragments using different materials and techniques

Objectives: When coronal fracture occurs in anterior teeth, fragment reattachment can be a valid alternative to a direct restoration. The aim of this study was to evaluate the influence of the material and the technique used to reattach the fragment. Materials and methods: Eighty sound maxillary and mandibular incisors were selected and randomly divided into eight groups (n = 10). The incisal third of each tooth was removed using a saw machine. The fragments in groups 1-4 were reattached using resin-based materials: group 1 adhesive, group 2 flow, group 3 composite, group 4 cement; in groups 5-8, the same materials mentioned before were used but a bevel was also performed on both labial and lingual surfaces. Shear bond strength (SBS) was calculated by applying a load incisal to the reattachment line. A two-way Anova was used to evaluate the influence of materials and techniques on the SBS. Results: The technique used was statistically significant (P < 0.001), while the material was not (P = 0.793). Conclusions: The choice of material seems to have no influence on the SBS, whereas a bevel performed on the labial and lingual surfaces can significantly improve the SBS of the reattached fragment.