Objective To investigate the stress distributions under load in an all-ceramic crown of the upper central incisor in differential thickness. Methods The 3-dimensional finite element model of all-ceramic crown of the upper central incisor in differential thickness was applied with differential loads（100, 150, 200 N）. The stress values and distributions of all-ceramic crown were calculated and expressed. Results The tendency of stress distributions in all-ceramic crown of differential thickness and loads was similar. The maximal stress intensity value was located in the loading site and the cervical region. As the thickness of all-ceramic crown increased, the stress concentration reduced. When the load increased, the stress values increased, especially in the loading site and the cervical region.
Conclusion The increasing of the thickness of all-ceramic crown will decrease stress concentration. Because stress concentration is mainly in cervical region and loading site, these regions should be cared in fabrication of all-ceramic crown.
