Effect of different framework materials on stresses induced at the implant/bone interface in all-on-four implant treatment concept: three-dimensional finite element analysis

Abstract

Background and aim Treatment of mandibular edentulous ridge with all-on-four treatment concept is a reliable choice. However, the framework material may affect the stresses transmitted to the implant and bone. The aim of the study was to compare stresses transferred to implant–bone interface on using glass fiber-reinforced composite (GFRC), zirconia (Zr), titanium (Ti) and poly-ether-ether-ketone (PEEK) as framework materials. Patients and methods Three-dimensional finite element model of completely edentulous mandible restored with four implants (two axial anterior implants and two posterior implants 30° distally tilted) connected with a framework of different materials (Zr, Ti, GFRC, and PEEK) was constructed. A unilateral axial load of 250 N was applied at the distal end of the cantilever and the resultant von Mises stresses at implant–bone interface were calculated. Results The lowest von Mises stresses at implant/crestal bone area was recorded with Zr framework followed by Ti then GFRC while the highest von Mises stresses were recorded with PEEK framework. Conclusions Within the limitations of this study, it could be concluded that the stiffer framework material transmits more stresses to the implants. The stress distribution of GFRC, as a framework material, is better than PEEK.