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Three-dimensional finite element analysis of titanium and yttrium-stabilized zirconium dioxide abutments and implants.

PURPOSE
The purpose of this study was to compare the von Mises (vM), compressive, and tensile stresses occurring on implants, abutments, and surrounding bone using three-dimensional finite element analysis (FEA) in three simulations in the anterior maxilla: a single titanium implant with a titanium abutment, a single titanium implant with a zirconia abutment, and a single one-piece zirconia implant.


MATERIALS AND METHODS
Three types of implants (all were 4 x 12 mm) were modeled using FEA: Astra OsseoSpeed implant with titanium abutment (ATt), Astra OsseoSpeed with zirconia abutment (ATz), and White-SKY (WS) one-piece zirconia dental implant. The anterior maxillary bone was also simulated with FEA. The implants were placed into the maxillary left central incisor region. Loading was applied horizontally and obliquely and the stresses were examined.


RESULTS
The vM and compressive stresses that occurred on the implant and cortical bone in the ATz model were lower than those seen in the ATt model. The tensile stress values observed in the abutment and cortical bone in the ATz and ATt models and all the stress values occurring in trabecular bone were similar. The stresses that occurred in the WS implant were lower than the stresses exerted on the ATt and ATz implants, except for tensile stresses under oblique loading.


CONCLUSION
Lower stresses occurred on the zirconia implant (WS), except for tensile stress under oblique loading. The zirconia implant generated the lowest stresses in cortical bone, and the zirconia abutment resulted in lower vM and compressive stresses than the titanium abutment in implant and cortical bone.