Reinforcing the lost margins with different approaches: An in vitro study

This study aimed to evaluate the fracture resistance of different restorative techniques in endodontically treated teeth with Mesial Occlusal Distal (MOD) cavities.

Sixty mandibular molars that were extracted were prepared with standardized MOD cavities and received root canal treatment. Samples were allocated randomly across four groups: Group 1 - preimpregnated glass fiber reinforced-composite (Interlig, Angelus, Brazil); Group 2 - invasive horizontal glass fiber posts (Waldent radiopaque fiber post, Waldent, India); Group 3 - noninvasive horizontal glass fiber posts (Waldent radiopaque fiber post, Waldent, India), and Group 4 - prepolymerized composite resin inserts. Fracture resistance was assessed using a universal testing machine, and the resulting data were subjected to statistical analysis using the analysis of variance (ANOVA) and Tukey's post hoc test.

The preimpregnated braided glass fiber reinforced-composite group showed the highest mean fracture resistance (2811.80 ± 227.83 N), followed by the noninvasive horizontal post group (2652.67 ± 191.59 N). The prepolymerized composite resin inserts group (1853.87 ± 210.59 N) had moderate resistance, while the invasive horizontal post group (1338.00 ± 187.05 N) exhibited the lowest values. Significant differences among groups were confirmed by ANOVA and post hoc tests (P < 0.05).

Within the study's limitations, preimpregnated glass fiber reinforced-composite provided the highest fracture resistance in endodontically treated MOD cavities, with noninvasive horizontal posts outperforming invasive posts. Preserving tooth structure through conservative glass fiber reinforcement yields superior clinical outcomes.