Abstract:

Abstract:Objective To explore the effect of different arch forms of maxillary models on stress distribution of peri-implant of All-on-4 implants with 3-dimensional finite element,and to provide evidence for the improvement of implant achievement ratio in clinic. Methods 3-dimensional finite element analysis models of Tapered,Square and Ovoid arch form maxillary based on the MBTTM Arch Form Templates were constructed by using Solidworks software.The cortical bone thickness was defined as 2 mm at all points.The implants with 13 mm in length were inserted between the mental foramina.The 2 posterior implants were set at 4 inclination angle,from 0°to 45°.All implants were splinted with superstructure.A 100 N pressure was applied to 2 kinds of loading positions on the superstructure models.The maximum Von-Mises stress on cortical bone around the implants was measured by using Abaqus software.Results The maximum Von-Mises value in maxillary cortical bone with All-on-4 implants in 3 arch forms showed significant differences.In Square model the concentration of stress was advanced with the increasing of implant inclination angle;In Ovoid model,the maximum Von-Mises value was observed at 15°in posterior region,and was increased significantly by pasted 15° in anterior region;In Tapered model,the Maximum Von-Mises value was increased greatly at 45°.Conclusion Arch forms have appreciable impact on stress distribution of peri-implant.In Square arch form,the inclination of implant should be avoided;in Ovoid arch form,the inclination angle should be under 15°;in Tapered arch form,the inclination should be under 30°.

Key words: All-on-4, arch form, dental implant, 3-dimensional finite element analysis