# Impact of framework material, cantilever design, and wing configuration on stress distribution in patient specific additively manufactured subperiosteal jaw implants: a 3D finite element analysis

## TL;DR

This study uses 3D modeling to analyze how different designs and materials affect stress in custom jaw implants, finding that certain configurations reduce stress and improve performance.

## Contribution

The study introduces a 3D finite element analysis to evaluate stress distribution in patient-specific jaw implants based on material, wing design, and cantilever use.

## Key findings

- Co-Cr implants with I-shaped design and no cantilever showed the lowest stress (444.5 MPa).
- Cantilevered designs increased prosthetic displacement, with PEEK showing more displacement than Co-Cr.
- Stress levels were significantly influenced by framework material, wing shape, and cantilever presence.

## Abstract

Recent advancements in digital technology have revolutionized implant dentistry, particularly with additively manufactured subperiosteal jaw implants (AMSJIs). These implants allow patient-specific designs that adapt to anatomical requirements. However, optimizing stress distribution remains a challenge.

This study evaluated the stress distribution in AMSJIs and surrounding bone by analyzing different framework materials (PEEK and Co-Cr), anterior wing designs (I- and Y-shaped), and cantilever extensions using three-dimensional finite element analysis.

A model was created from a patient with an atrophic, edentulous maxilla. Biomechanical evaluation of eight maxillary implant scenarios was performed under a 200 N force applied at a 45° oblique angle. Stress distribution in the bone, implants, screws, and prosthetic frameworks, as well as prosthetic displacement, was analyzed.

The lowest implant stress (444.5 MPa) was observed in the Co-Cr group without a cantilever using an I-shaped design, whereas the highest stress (623.0 MPa) occurred in the Co-Cr group with a cantilever using a Y-shaped design. Prosthetic displacement was greater in cantilevered groups, with PEEK exhibiting more displacement than Co-Cr.

The optimal stress distribution was achieved with the I-shaped design without a cantilever, using Co-Cr. Stress levels were significantly influenced by framework material, wing design, and cantilever presence, underscoring the importance of design and material selection.

While stress remained within physiological limits in all cases, avoiding cantilevers and selecting a rigid material can optimize Y-shaped designs. PEEK demonstrated favorable properties in cantilevered designs, but its long-term effects on soft tissue and implants warrant further clinical trials.