Indexed on: 30 Jul '20Published on: 30 Jul '20Published in: Journal of Endodontics
The aim of this study was to evaluate the fracture resistance and fracture patterns of endodontically-treated maxillary premolars with wedge-shaped cervical lesions restored with resin composite core with/without a fiber post under non-axial loading. Sixty extracted human maxillary premolars with two root canals were randomly allocated into 4 groups (n=15). Forty five teeth were prepared a wedge-shaped lesion at the buccal cervical area and root canal treatment. There were three restoration groups: no restoration (EB), restoration with resin composite core (EBC), and restoration with resin composite core and a fiber post (EBP). Intact teeth served as the control group. All teeth were subjected to thermocycling and cyclic loading. A 45 compressive load was applied to the palatal plane of buccal cusp until tooth fracture. The fracture resistance and facture patterns were analyzed using one-way ANOVA and Chi-square test (α=0.05), respectively. The EB group demonstrated the lowest fracture resistance and was significantly different from other groups (P<0.001). The intact teeth presented the highest fracture resistance, which was not significantly different from the EBP group (P>0.05). The failure patterns were significantly different between groups (P<0.001). Most intact teeth fractured coronal to the CEJ level, while most teeth in other groups fractured at the gingival margin of cervical lesion. Endodontically-treated maxillary premolars, with wedge-shaped cervical lesions, restored with fiber posts and resin composite cores had a fracture resistance equivalent to intact teeth. However, their fracture patterns were not improved by the fiber post and resin composite core. Copyright © 2020. Published by Elsevier Inc.