Stress Distribution Analysis Implant-Supported Fixed Prostheses with Different Fabrication Orientations 3D Printed Monolithic Zirconia:FEA
Ayyüce Nur Tezcan, Reza Mohammadi, Assoc. Prof. Mehmet Gökberkkaan Demirel, Assoc. Prof. Mehmet Esad Güven
Necmettin Erbakan University
Objectives
Advancements in additive manufacturing now permit the creation of intricate structures while reducing material waste and costs, leading to its increased adoption in ceramic production. This study aims to evaluate the stress distribution in 3D printed zirconia crowns with varying manufacturing orientations on different implant abutments through finite element analysis..
Materials and Methods
Three different three-dimensional models were designed for a single-unit implant-supported fixed prosthesis according to the type of abutment (multi-unit, cemented, ti-base) using SolidWorks software. All models were positioned in the mandibular bone at the site of tooth 44. The crown designs were created in the Exocad design program, positioned on the implants in SolidWorks, and the resulting .stp files were used for finite element analysis. The abutment material was specified as titanium, the cement as dual-cure resin cement, and the prosthetic restoration as 3D printed 3Y-TZP zirconia (in both vertical and parallel fabrication orientations). A 150 N load was applied obliquely at a 30-degree angle buccolingually across the entire occlusal surface, and stress distribution was examined. The obtained stress distribution values were reported as von Mises Stress Values (vMS).
Results
Among all models, the lowest von Mises stress values for the restorations were observed in models produced with the parallel method, whereas the lowest stress values for implant components were recorded in models fabricated vertically. Furthermore, across the three different abutment designs for implant components and restoration materials, the highest stress values appeared in ti-base models, while the lowest stress values were found in multi-unit models.
Conclusions
In implant-supported fixed prostheses, excessive stress in implant components has been observed, which could lead to catastrophic failure. This FEA study demonstrates that models with parallel orientations exhibited lower stress in restorations, whereas higher stress was observed in implant components. These results should be re-evaluated with in-vitro models.