Influence of Restorative Material Properties on Dentin Stress Distribution: A 3D Finite Element Analysis of Bioflx and Zirconia Crowns

Aim: The aim of this study is to evaluate the effect of restorative crown materials with different elastic moduli on stress distribution in dentin and supporting tissues of pulpotomized primary anterior teeth under multi-directional loading conditions using the three-dimensional finite element analysis method. Materials and Methods: A three-dimensional model of a maxillary primary central incisor was created based on anatomical data. A clinical pulpotomy scenario was simulated using mineral trioxide aggregate (MTA) and resin-modified glass ionomer cement. Three models were analyzed: healthy tooth (control), Bioflx crown, and prefabricated zirconia crown. Frontal, oblique, and vertical loads were applied to represent functional and traumatic conditions. von Mises and principal stress distributions in the crown, dentin, and supporting tissues were evaluated. Results: In the prefabricated zirconia crown group, higher von Mises stress values were observed under all loading conditions, with significant stress concentrations particularly in the cervical region. In contrast, the Bioflx crown group exhibited lower stress values and a more homogeneous stress distribution. While the stress patterns in the Bioflx group were found to be closer to those of the control group, more localized stress accumulation was observed in the zirconia crowns. No significant differences were observed between the groups in the bone tissue. Conclusions: The elastic modulus of restorative materials plays a decisive role in the stress transfer mechanism. It is believed that materials with dentin-like mechanical properties may provide a more balanced and physiological stress distribution. Multi-directional loading analysis highlights the importance of evaluating the biomechanical behavior of restorative materials under more realistic conditions. Further advanced experimental and clinical studies are needed to clinically validate these findings.