Restorative strategies and fracture resistance in simulated immature endodontically treated teeth: An ex vivo study

Abstract Background: Immature teeth with necrotic pulps present clinical challenges for both endodontic and restorative management, particularly due to thin dentinal walls and incomplete root formation. Effective treatment should maintain tooth integrity and reduce fracture risk, especially in the cervical region. Aim and Objectives: This study evaluated the effect of different restorative protocols on the fracture strength of immature teeth. Material and Methods: Simulated immature permanent teeth were randomly allocated into four groups: control, fiber post, gutta-percha terminating 3 mm apical to the cementoenamel junction (CEJ), and gutta-percha terminating at the CEJ. Specimens were standardized to Cvek stage 3 root development. Fracture strength was assessed using an Instron universal testing machine. Results: Statistical analysis revealed no significant differences in fracture resistance between groups (Kruskal–Wallis; p = .179). However, fracture pattern differed significantly (Fisher-Freeman-Halton exact test; p = .014). Post-hoc analysis showed the control group had a greater proportion of fractures confined to the crown (58%; p = .0031), whereas the gutta-percha–at-CEJ group showed a higher incidence of root fractures (50%; p = .0264). Conclusions: Within the limitations of this study, the restorative protocol did not significantly alter fracture strength in endodontically treated immature teeth. Nevertheless, terminating gutta-percha 3 mm apical to the CEJ and restoring the remaining canal space and pulp chamber with composite may offer a cost-effective strategy to help reduce the risk of non-restorable fractures. Fiber posts performed similarly but did not appear to provide additional benefit.