Abstract: The implant-to-bone contact stress following magnitudes of interference, which indicated the differences of the diameter between the implant and the receipting bone cavity at the interface, are calculated with the contact element method (CEM). The model of cubiform bone and columniform implant is developed based on clinic. The results indicat that the stress distribution is asymmetric with axis of implant. Stress magnitudes correlate strongly to those of interference. The maximum occurrs in direction of the medial-distal aspect in cortical bone layer and the minimum the buccal-lingual area on the bottom line in the cancellous bone. Along the radius, stresses decrease with the distance from the central point. Cortical bone contribute more to implant retention than cancellous bone. Coating has little effect on the contact pressure at the interface.

Key words: Contact element stress, Contact stress, Femur, Implant-bone interface, Magnitude of interference