Biomechanics effect of two implant system with different bone height under axial and non–axial loading conditions

The objective of this current in silico study was to evaluate the influence of axial and non-axial loads on unitary implant-supported implants, with external hexagon or Morse-taper connection in two different bone level, using finite element analysis. Two implant models with the same length (13 x 3.75 mm) were analyzed according to the prosthetic connection (external hexagon or morse Taper) and bone height (bone level or 5 mm of bone loss). Both implant systems received screw-retained metallic crowns in chromium-cobalt. The peri-implant tissue was simulated as an isotropic material (polyurethane resin). The polyurethane block has been fixed and a load of 300 N was applied on the occlusal surface in two different directions (Axial or Non-axial) for each implant model and bone condition. The results were analyzed in terms of von-Mises stress and bone microstrain. The materials were considered isotropic, homogeneous, linear and elastic. The results showed that there is no difference regarding the prosthetic connection for the generated stress and strain under the same load incidence. However, bone loss and non-axial loadings increased the stress and strain magnitude regardless the prosthetic connections. In conclusion, the load incidence is more prone to modify the implant stress and bone microstrain than the prosthethic connection. In addition, the higher the bone loss the higher the stress and strain magnitude generated, regardless the loading condition.