Comparative Evaluation of Fracture Resistance of Teeth With Internal Resorption Cavities Repaired With Three Different Materials.

Introduction Internal root resorption is a relatively uncommon pathological condition characterized by progressive loss of intraradicular dentin due to clastic cell activity. If left untreated, continued resorption weakens the remaining tooth structure, predisposing the tooth to perforation and fracture. Following endodontic management, repair of the resorptive defect using a material that provides both an effective seal and reinforcement of the weakened root is essential. Although mineral trioxide aggregate (MTA) is widely regarded as the material of choice because of its excellent biocompatibility and bioactivity, short fiber-reinforced composite (SFRC) has recently emerged as a promising alternative owing to its superior mechanical properties and crack-arresting ability. Aim To evaluate and compare the fracture resistance of simulated internal resorption defects repaired with SFRC, MTA, and gutta-percha (GP) (control). Materials and methods Thirty extracted human single-rooted teeth were instrumented, and standardized internal resorption defects were prepared. The specimens were randomly divided into three groups (n = 10): Group I, GP (control); Group II, МТА; and Group III, SFRC. Following repair of the defects, specimens were subjected to compressive loading in a universal testing machine until fracture. Fracture resistance values were recorded in Newtons and analyzed using one-way ANOVA and Tukey's HSD post hoc test (α = 0.05). Results The SFRC group exhibited the highest mean fracture resistance (1,476.29 ± 100.49 N), followed by the MTA group (1,021.78 ± 65.67 N), while the GP group demonstrated the lowest fracture resistance (829.78 ± 72.74 N). One-way ANOVA revealed a highly significant difference among the groups (F = 167.84, p < 0.001). Pairwise comparisons showed statistically significant differences between all groups. Conclusion Within the limitations of this in vitro study, repair of internal resorption defects using SFRC significantly improved fracture resistance compared with MTA and GP. SFRC may therefore represent a promising material for reinforcing teeth weakened by internal resorption.