Evaluation of Stresses Occurring on Three Different Zirconia Dental Implants: Three-Dimensional Finite Element Analysis

Purpose: The aim of this study was to evaluate the von Mises, compressive, and tensile stresses occurring on three different zirconia dental implants and surrounding bone with three-dimensional finite element analysis. Materials and Methods: Three different zirconia implants (Z-Systems, Ziterion, and White-Sky), 10 mm in length and 4 mm in diameter, and anterior maxillary bone were modeled using three-dimensional finite element analyses. Zirconia implants were placed into the maxillary left central incisor region. Loading was applied in horizontal and oblique axes (at angles of 90 and 30 degrees with respect to the implant long axes). Oblique loading was 178 N and horizontal loading was 25.5 N. Results: Under oblique loading, von Mises stresses for all implants were similar, and under horizontal loading conditions, the highest von Mises stress was found at the buccal and palatal neck region of the Ziterion implant (46.57 MPa). In cortical bone, the highest von Mises stresses were observed at the buccal region of the Z-Systems implant under oblique and horizontal loading conditions (26.65 MPa and 10.74 MPa, respectively). The highest compressive stresses were observed at the implant buccal neck region and cortical bone interface of the Z-Systems implant under oblique and horizontal loading conditions. For both loading conditions, the highest tensile stress values were observed at the implant palatal region and cortical bone interface of the Z-Systems implant. Conclusion: The von Mises, compressive, and tensile stresses that occurred in cortical bone were higher than those observed in trabecular bone. Generally, the stresses in the Z-Systems implant were higher than in the other zirconia implants. The differences between the stress values occurring on the zirconia implants may be related to the different body and thread designs of these implants. Keywords: compressive stress, dental implants, finite element stress analysis, tensile stress, von Mises stress, zirconia