Biomechanical Evaluation of Maxillary Central Incisors After Regenerative Endodontic Treatment: An Extended Finite Element Analysis.

INTRODUCTION

To undertake an in-silico analysis of two maxillary central incisors treated with regenerative endodontic treatment (RET) where the right incisor did not undergo further root maturation and compare it to the left central incisor where further root maturation occurred.

METHODS

This study employed eXtended Finite Element Analysis to evaluate the fracture resistance of maxillary central incisors treated with RET. Post-treatment cone beam computed tomography data were used to reconstruct two 3D tooth models. Both models were subjected to two physiologically relevant loading conditions: biting (300 N at a 60° angle to the tooth's long axis) and trauma (300 N perpendicular to the labial surface). The mechanical behaviour was assessed by extracting stress distributions, force-displacement curves, and crack propagation behaviour.

RESULTS

Biting generated lower peak tensile stress (∼30 MPa) than trauma (∼45 MPa, ∼50% higher), with trauma causing stronger cervical stress concentrations. The mature root showed greater stiffness (4.5 kN/mm vs 3.9 kN/mm, ∼15% higher). Crack initiation occurred at 100 N under biting and 60 N under trauma (∼40% lower threshold). Biting produced more stable crack growth, whereas trauma caused earlier initiation and faster propagation. Overall, root maturation improved stiffness and fracture resistance, particularly under lateral trauma.

CONCLUSIONS

The mature root exhibited higher stiffness and more stable crack progression, likely due to thicker dentine walls and enhanced structural support. These findings suggest that RET-treated teeth with less mature roots may not experience higher stress under load, but their reduced resistance to crack growth poses a higher fracture risk.