The comparison of angular and curvilinear marginal mandibulectomy on force distribution with three dimensional finite element analysis

The purpose of this study is to analyse and compare right angled and curved osteotomy design on stress distribution and to determine an osteotomy design which decreases the risk of pathologic fracture.Solid mathematical model of the mandible was created by three dimensional finite element analysis and two different osteotomy was performed on model, right angled and curvilinear osteotomy lines.150 N incisor force vertically and 250 N molar force to the angulus area oblically was applied. The effects of osteotomy types to the stress formation and risk of fracture between models were evaluated.Right angled osteotomy causes much more stress in the posteroinferior quadrant and mainly localized on the horizontal and vertical osteotomy intersection area. On the other hand, the distribution of the stress on curvilinear formed osteotomy shows posteroinferior localization and stress spreads wider area. Furthermore the amount of stress was less than right-angled one.In this study, curved osteotomy denominated less stress distribution. The shape of osteotomy might be a factor to decrease the risk of postoperative atrophic mandible fracture.Key Words: Curved osteotomy, Marginal mandibulectomy