3D-FEA of osseointegration percentages and patterns on implant-bone interfacial stresses

Objectives: The degree of osseointegration and its patterns are important for the success of implants. 3D-FEA was used to determine interfacial stresses on a single tooth implant (IMZ) for four degrees of osseointegration (100, 75, 50 and 25%), and five patterns at 50% osseointegration (locally alternating, coronal only, apical only, facial only and lingual only). Methods: The implant was restored with a metal-ceramic crown and subjected to 10 MPa axial or oblique applied stress. Resolved stresses were examined at four heights along the implant-bone interface. Results: The degree of osseointegration did not affect resolved stress levels or distributions. Oblique loads elevated interfacial stresses 5 to 20 times. Stresses were always higher at the bone crest. Conclusions: Osseointegration patterns with crestal bone reduced both crestal and apical stresses. Apical only osseointegration produced much higher apical stresses. Crestal osseointegration and axial loads minimized overall stress.