Distortion of the Implant-Framework Interface of Screw-Retained CoCr Ceramic Fixed Dental Prostheses Following Ceramic Veneering: An In Vitro Study.

The article focuses on evaluating the effect of ceramic firing cycles on the distortion of the implant-framework interface (IFI) in screw-retained cobalt-chrome (CoCr) metal-ceramic fixed dental prostheses (FDPs). Using a coordinate measuring machine (CMM), the study measured 3D distortions before and after ceramic firing cycles on 22 CAD/CAM-produced CoCr frameworks. Results showed that while ceramic firing induced statistically significant 3D distortions at the IFI, these distortions (approximately 10.5 µm) remained well below clinically relevant thresholds and did not compromise the precision or clinical functionality of the prostheses. The study concludes that CAD/CAM manufacturing provides highly accurate IFIs, and despite measurable distortions from ceramic firing, the process remains a reliable method for producing implant-supported metal-ceramic FDPs.