Document Type: Original Article

Author

Assistant Professor of Orthodontic Department, School of Dentistry, Shiraz University of Medical Sciences

Abstract

The main goal of this research was to evaluate the stress produced in tooth, PDM, spongy bone, and cortical bone consequent to force application (1 N) to the crown of anupper central incisor, while the alveolar bone resorbs gradually. Four 3-dimensional FEM models were designed (ARGue392-5) with the same form except for their alveolarbone support that represented 1, 2.5,5, and 6.5 mm of reduction. All the output data were compared with a normal model (ARGue391). Normal stress in palato-labial   yz,  yx) were evaluated. A progressive increase in all stress forms were found in all of the involved tissues in gradual steps of alveolar bone loss. Based upon this study, 2.5 mm of alveolar bone loss can be considered as the limit beyond which the normal stress changes accelerate. This limit is 5 mm for theshearing stresses. There were some clinical suggestions on the manner of force application and the appliance selection, based on the findings of this study, in the article.Key words: Finite Element Analysis, Alveolar Bone Resorption, Stress Tensor