Effect of a thin HA coating on the stress/strain distribution in bone around dental implants using three-dimensional finite element analysis

Three-dimensional finite element analysis was performed for thin hydroxyapatite (HA) coated and titanium dental implants to study the effects on stress/strain distribution in the mandible with application of axial and oblique loads. The implants were of screw and cylinder types. With an axial load, the maximum equivalent bone stresses in the titanium implants were 21.5 and 29.0 MPa for the cylinder and screw types respectively, and the stress and strain distributions differed. For the cylinder type, the highest stress was located at the implant base, and for the screw type, it was located at the top edge of the first thread within the cortical bone. For the HA-coated cylinder and screw implants, the maximum equivalent bone stresses were 7.1 and 7.2 MPa respectively. The stress and strain distributions were similar, and the highest stress was located on the upper side of the cortical bone around the implant neck for both implants. Of the implants examined, the screw type HA-coated implant had the most uniform stress distribution in bone.