Three-dimensional Finite Element Analysis of Quad Zygomatic, Transnasal and Pterygoid Implants for Rehabilitation of Patients with a Severely Atrophic Maxilla.

Abstract

Purpose: The aim of this study is to compare the effects of different occlusal forces on quad zygoma, transnasal and pterygoid implants in patients with severely atrophic maxilla using finite element analysis.

Materials and methods: Using cone beam computed tomography data from a patient with a severely atrophic maxilla, a three-dimensional finite element analysis model was created. Three models were developed: Model 1, a quad zygoma model with four zygomatic implants placed using the extrasinus technique; Model 2, a combination of one zygomatic implant placed using the extrasinus technique and one transnasal implant; and Model 3, with transnasal, zygomatic and pterygoid implants. Two different forces were applied: a 150 N vertical force at the first, second premolar and the first molar region and functional force consisting of a 100 N vertical force combined with a 50 N horizontal force at the same locations. Stress values in the bone, implants, abutments and prosthetic framework were evaluated.

Results: The quad zygoma model (Model 1) demonstrated the highest stress values on the implant, abutment, and prosthetic framework under both vertical and functional forces. Model 2, which included transnasal and zygomatic implants, showed lower stress values compared to Model 1. Model 3, supported by pterygoid implants, exhibited lower stress levels on the bone, implants, abutments and prostheses compared to the other models.

Conclusions: According to the results of our study, the use of transnasal implants with zygomatic implants presents a method as an alternative to quad zygoma protocol. Additionally, in the model supported by pterygoid implants, the absence of cantilevers resulted in reduced stresses on the bone, implant, abutment, and prosthetic framework. We recommend the application of pterygoid implants alongside zygomatic and transnasal implants for long-term success and the prevention of biomechanical complications in the rehabilitation of severely atrophic maxilla.