SUMMARYThis study evaluated the stress distribution on an endodontically treated maxillary central incisor restored with different post-and-core systems by using a three-dimensional finite element analysis model. Seven three-dimensional finite element models were created. Each model contained cortical bone, cancelous bone, periodontal ligament, 3 mm apical root canal filling, post-andcore and all-ceramic crowns. Two different prefabricated zirconia ceramic post systems, a glass fiber-reinforced post system and a titanium post system were modeled. As a control, an all-ceramic crown on an endodontically treated maxillary central incisor without a post-and-core was modeled. Each model received a 45°oblique occlusal load at a constant intensity of 100 N. In each model, the ratio of Von Mises stress distribution was compared. The greatest stresses were observed in the coronal third of the roots on facial surfaces. The ratio of Von Mises stress distribution in dentin for the zirconia ceramic post According to FEA analysis, under a simulated occlusal load, the cervical area of endodontically treated and crowned maxillary central incisors was the most stress concentrated area. Zirconia ceramic posts create slightly less dentinal stress concentration than titanium and glass-fiber posts. 90Operative Dentistry stress concentrations in dentin created by two different zirconia ceramic post systems were nearly the same. The zirconia ceramic post systems created slightly less stress concentration in dentin than the glass fiber-reinforced and titanium posts.