MATERIALS AND METHODS FOR EVALUATING ZIRCONIA ALTERNATIVES IN IMPLANT-SUPPORTED PROSTHESES

The demand for metal-free dental restorations has driven the development of materials that emulate natural tooth structure. This study aimed to compare the stress distribution in implant-supported fixed prostheses made from zirconia and polyoxymethylene (POM) using the finite element method. Three- dimensional models represented screw-retained prostheses on cylindrical external hexagon-type implants in the mandibular region. The experimental group used a POM base, and the control group used zirconia, both with the same geometry. Results indicated a significant increase in stress under the zirconia abutment, with higher intensity transmitted to other components. A 41.96 MPa stress variation was observed in the prosthetic screw with a POM base compared to zirconia. No significant differences were noted in bone tissue stress between the two materials. In conclusion, POM demonstrated superior stress dissipation, potentially reducing mechanical failure risks.