Nurullah Türker1, Ulviye S Büyükkaplan1, Steven J Sadowsky2, Mehmet M Özarslan1. 1. Department of Prosthodontics, Akdeniz University Faculty of Dentistry, Antalya, Türkiye. 2. Preventive and Restorative Department, University of the Pacific Arthur A. Dugoni School of Dentistry, San Francisco, CA.
Abstract
PURPOSE: The aim of this study was to evaluate stress distributions on implants and alveolar bone due to occlusal load produced during chewing by prostheses prepared according to the All-on-Four concept with different occlusal schemes using a finite element analysis method. MATERIALS AND METHODS: On standard jaw models, teeth were set in accordance with the basic standards of canine-guided occlusion, group function occlusion, bilateral balanced occlusion (BBO), lingualized occlusion, and monoplane occlusion schemes. Three-dimensional (3D) images of these models were obtained using a surface scanner. Implants, superstructures, the maxilla, and mandible were modeled in the All-on-Four concept with 3D modeling software. Forces were defined on contacts formed in maximum intercuspation, lateral, and protrusive movement position for all 5 occlusion types. Stress outputs were recorded as maximum and minimum principal stresses (Pmax , Pmin ) and von Mises stress values for the implants. RESULTS: The highest Pmax value for the maxilla was observed in cortical bone in the group function occlusion during lateral movement (15.56 MPa). For the mandible, the highest Pmax value was observed on the cortical bone in maximum intercuspation of lingualized occlusion (72.75 MPa). The highest Pmin value for the maxilla was observed during the lateral movement in group function and for the mandible in BBO (-29.23 and -86.31 MPa, respectively). The lowest stress values were observed with canine-guided occlusion in all related conditions and on all structures. CONCLUSIONS: With the limitations of this simulation study, considering stresses on alveolar bone and implants in All-on-Four applications, the use of canine-guided occlusion may be suggested.
PURPOSE: The aim of this study was to evaluate stress distributions on implants and alveolar bone due to occlusal load produced during chewing by prostheses prepared according to the All-on-Four concept with different occlusal schemes using a finite element analysis method. MATERIALS AND METHODS: On standard jaw models, teeth were set in accordance with the basic standards of canine-guided occlusion, group function occlusion, bilateral balanced occlusion (BBO), lingualized occlusion, and monoplane occlusion schemes. Three-dimensional (3D) images of these models were obtained using a surface scanner. Implants, superstructures, the maxilla, and mandible were modeled in the All-on-Four concept with 3D modeling software. Forces were defined on contacts formed in maximum intercuspation, lateral, and protrusive movement position for all 5 occlusion types. Stress outputs were recorded as maximum and minimum principal stresses (Pmax , Pmin ) and von Mises stress values for the implants. RESULTS: The highest Pmax value for the maxilla was observed in cortical bone in the group function occlusion during lateral movement (15.56 MPa). For the mandible, the highest Pmax value was observed on the cortical bone in maximum intercuspation of lingualized occlusion (72.75 MPa). The highest Pmin value for the maxilla was observed during the lateral movement in group function and for the mandible in BBO (-29.23 and -86.31 MPa, respectively). The lowest stress values were observed with canine-guided occlusion in all related conditions and on all structures. CONCLUSIONS: With the limitations of this simulation study, considering stresses on alveolar bone and implants in All-on-Four applications, the use of canine-guided occlusion may be suggested.
Authors: João Paulo Mendes Tribst; Dayana Campanelli de Morais; Jefferson David Melo de Matos; Guilherme da Rocha Scalzer Lopes; Amanda Maria de Oliveira Dal Piva; Alexandre Luiz Souto Borges; Marco Antonio Bottino; Antonio Lanzotti; Massimo Martorelli; Pietro Ausiello Journal: Dent J (Basel) Date: 2022-01-14