The present research was conducted to determine the optimum implant diameter that achieves the most favorable stress distribution pattern along the implant in various bone width cases under various forces to guarantee the desired implant prognosis

This study was directed to use the Three Dimensional Finite Element Method (ABAQUS software) to analyze the stress distribution pattern of several implant diameters (3.4, 3.9, 4.4 mm). The tested implant was housed in different bone thickness sections (8, 12, 16 mm) modeled as a trabecular core surrounded by a 1.5 mm layer of cortical bone with the mesial and distal section planes not covered by cortical bone

The implant was subjected to variable load magnitudes of axial compressive load equal to 173 N, tensile load equal to 63 N and horizontal load equal to 57 N along different directions

Several forms of results had been obtained as a parametric values which were, contour pattern tables, limits, curves of stresses along paths with statistical tables and proposed equations

It was noticed clearly that all the stresses were mainly concentrated in the trabecular and cortical bone at the implant collar area

The study showed that, the optimum implant diameter necessary for long term success depends on the bone width supporting the implant as well as the loading condition