Is zirconium or stainless steel the most suitable crown material for less dentin stress in endodontically treated teeth?

BACKGROUND: Stainless steel crowns (SSCs), which have been used frequently in the treatment of first permanent molars in children until now, has become less applicable due to its poor aesthetic appearance. Zirconia crowns (ZCs) have become more popular due to their aesthetic advantage. However, stress transmission of ZCs to dental tissues under occlusal forces in endodontically treated teeth has not been described. OBJECTIVE: The aim of this study was to compare the stress distribution of different crown materials (ZCS, SSCs) and adhesive materials on dentin in endodontically treated permanent teeth and to specify the crown-adhesive model with lower stress. METHODS: Finite element analysis (FEA) was used to apply a force of 300 N from the inner part of the buccal tubercles (vertical loading) and a lingo-buccal at an angle of 30 degrees (oblique loading) of the first permanent molars (FPM) with different crown (ZCS, SSCs) and adhesive (Glass ionomer cement, Resin modified glass ionomer cement, Resin cement) materials in twelve separate models. The von Mises values obtained from the models were compared and the optimal stress values were determined by FEA. RESULTS: The lowest stress values of dentin were found in zirconia crown model with glass ionomer cement (GIC) adhesive under vertical loading (26,793 Mpa). In the zircon crown and GIC adhesive model, less von Mises stress occurred on the dentin under all conditions. CONCLUSIONS: ZCs and GIC adhesive may be recommended for teeth with a high probability of dentin fracture.