Axial symmetrical finite element models provide less accuracy in the results as they are not able to interpret completely the real three dimensional response with regard to the geometric characteristics, material anisotropy and general loading conditions. In spite of this limit they can be used for an easy and immediate preliminary information about the biomechanical response of dental implants.
In Fig. 1 a simple axial symmetrical model of a threaded implant is reported.
Different values of the Young's modulus are assumed for the different regions of bone. These values are set according to an orthotropic scheme. Average elastic values for human mandible bone, reported in table 4 of "Mechanical properties of bone" section, are adopted. A distinction is made between cortical and trabecular bone with regard to the periimplant region, as healing and functional adaptation processes mostly take place in this zone and strongly affect the biomechanical efficiency of the dental implant. Loads are assumed according to average data reported in literature and representing physiological conditions.