Comparison of Four Implant-Supported Fixed Rehabilitation Options of the Edentulous Mandible: A 3D Finite Element Analysis

Abstract

Aim: This study aims to compare four implant-supported rehabilitation concepts of an edentulous mandible and determines the most biomechanically advantageous technique. Materials and Methods: Five models with four implants in different configurations were formed: four axial interforaminal implants, All-on-4 concept (two anterior axial and two posterior distally tilted implants), All-on-4v4 concept (four distally tilted interforaminal implants), All-on-4W (two anterior mesially tilted and two posterior distally tilted implants), and two axial interforaminal implants and two posterior extra-short implants. Straumann bone-level (4.1 x 12 mm) and tissue-level (4.1 x 4 mm) extra-short implants were used for this study. Spherical loadings from canine and molar regions were applied to evaluate tension, compression, and von Mises stresses by implementing 3D finite element analysis. Results: Among the alternative concepts, the classic All-on-4 and the All-on-4v4 techniques were the most successful treatment option in biomechanical terms. On the other hand, the use of extra-short implants in the posterior region was found to be the last method of choice. This was because of the high stresses on bones in most conditions, even though it balances the forces from the molar region on the implants. Conclusion: The results of the present study indicate that the classic All-on-4 and the All-on-4v4 techniques were the most successful treatment options in biomechanical terms for the rehabilitation of an edentulous mandible with four implant-supported fixed full-arch prostheses.