Comparison of stress distribution around vertical and angled implants with finite-element analysis

The distribution of stress around implants placed in the first molar region of the mandible was biomechanically analyzed in a two-dimensional mathematical model. Two types of implants, vertical and angled, were subjected to a vertical load of 100 N and a horizontal load of 50 N in turn. The magnitudes and contours of compressive and tensile stress within the surrounding bone were determined. For the sake of comparison, maximal compressive stress and maximal tensile stress at the surrounding bone were calculated. There were no measurable differences in stress values and contours when a horizontal load was applied to the vertical and angled implants. However, with the vertical loading, the compressive stress values were five times higher around the cervical region of the angled implant than around the same area in the vertical implant.