Related Experiment Video
Updated: May 22, 2026

Quasistatic Mechanical Testing for Computer-Aided Design and Manufacturing Occlusal Veneers Cemented to Milled Dentin Analog Material
Published on: December 20, 2024
Influence of crown-to-implant ratio, retention system, restorative material, and occlusal loading on stress
Bruno Salles Sotto-Maior1, Plinio Mendes Senna, Wander Jose da Silva
1Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas-UNICAMP, Piracicaba, São Paulo, Brazil.
Purpose:
The aim of this study was to assess the contributions of some prosthetic parameters such as crown-to-implant (C/I) ratio, retention system, restorative material, and occlusal loading on stress concentrations within a single posterior crown supported by a short implant.
Materials And Methods:
Computer-aided design software was used to create 32 finite element models of an atrophic posterior partially edentulous mandible with a single external-hexagon implant (5 mm wide x 7 mm long) in the first molar region. Finite element analysis software with a convergence analysis of 5% to mesh refinement was used to evaluate the effects of C/I ratio (1:1; 1.5:1; 2:1, or 2.5:1), prosthetic retention system (cemented or screwed), and restorative material (metal-ceramic or all ceramic). The crowns were loaded with simulated normal or traumatic occlusal forces. The maximum principal stress (stressmax) for cortical and cancellous bone and von Mises stress (stressvM) for the implant and abutment screw were computed and analyzed. The percent contribution of each variable to the stress concentration was calculated from the sum of squares analysis.
Results:
Traumatic occlusion and a high C/I ratio increased stress concentrations. The C/I ratio was responsible for 11.45% of the total stress in the cortical bone, whereas occlusal loading contributed 70.92% to the total stress in the implant. The retention system contributed 0.91% of the total stress in the cortical bone. The restorative material was responsible for only 0.09% of the total stress in the cancellous bone.
Conclusion:
Occlusal loading was the most important stress concentration factor in the finite element model of a single posterior crown supported by a short implant.
Related Concept Videos
Stress Concentrations
Stress Concentrations
The stress concentration...
Stress: General Loading Conditions
The shearing force, possessing potential directionality within the plane of the section, is simplified into two component forces running parallel to the x and y axes.
Stresses under Combined Loadings
The process begins by slicing the tube at critical points and analyzing the internal forces and stress components at these sections, focusing on the centroid. Normal stresses, generated by axial forces and bending moments, are either compressive or tensile and vary across the section from...
Stress Concentrations in Circular Shafts
Components of Stress
Interestingly, the hidden cube faces also experience these stresses, equal and opposite to those on the...
