Influence of superstructure geometry on the mechanical behavior of zirconia implant abutments: a finite element analysis

Abstract

To predict the clinical performance of zirconia abutments, it is crucial to examine the mechanical behavior of different dental implant-abutment connection configurations. The international standard protocol for dynamic fatigue tests of dental implants (ISO 14801) allows comparing these configurations using standardized superstructure geometries. However, from a mechanical point of view, the geometry of clinical crowns causes modified boundary conditions. The purpose of this finite element (FE) study was to evaluate the influence of the superstructure geometry on the maximum stress values of zirconia abutments with a conical implant-abutment connection. Geometry models of the experimental setup described in ISO 14801 were generated using CAD software following the reconstruction of computerized tomography scans from all relevant components. These models served as a basis for an FE simulation. To reduce the numerical complexity of the FE model, the interaction between loading stamp and superstructure geometry was taken into account by defining the boundary conditions with regard to the frictional force. The results of the FE simulations performed on standardized superstructure geometry and anatomically shaped crowns showed a strong influence of the superstructure geometry and related surface orientations on the mechanical behavior of the underlying zirconia abutments. In conclusion, ISO testing of zirconia abutments should be accompanied by load-bearing capacity testing under simulated clinical conditions to predict clinical performance.

Influence of Luting Materials on the Retention of Cemented Implant-Supported Crowns: An In Vitro Study

“…However, cobalt–chromium crowns exhibit lower detail accuracy and higher shrinkage after casting than gold alloys [ 30 ]. The superstructure geometry and related surface peculiarities influenced the mechanical behavior of the various abutment–prosthesis (crown) connections [ 38 , 39 ]. A conical connection between abutment and crown was performed because in vivo studies revealed significantly lower bacterial counts in the peri-implant sulci and inside the connections in the internal hexagons of the external collar connection and conical connection groups [ 4 , 40 ].…”

Evaluation of Stresses on Implant, Bone, and Restorative Materials Caused by Different Opposing Arch Materials in Hybrid Prosthetic Restorations Using the All-on-4 Technique

“…One of the key factors for long-term clinical success is correct planning of the substructure and superstructure materials that support the implant prosthesis. The properties of the material and spatial geometric configuration model of each component have a significant impact on the transference of functional loads and stress distribution in a bone–implant–prosthesis assembly [ 2 ]. In the oral environment, these components act in unison with each other, and thus the combination of the materials used is important.…”

The compressive strength of implant-abutment complex with different connection designs

“…This International Standard is most useful for comparing endosseous dental implants of different designs or sizes 18 , 19 . Several previous studies compared different implant designs applying this protocol in terms of stress and strain distribution, 20 , 21 torque evaluation, 13 , 22 and bending moment 23, 24, 25. By using the same protocol, comparing between different studies could be possible.…”