Stress Distribution in Different Permanent Fixed Restorative Materials with Different Connector Dimensions: A 3D Finite Element Analysis

The aim of this in vitro study is to evaluate the stress distribution of different definitive restorative materials designed with different connector dimensions using finite element analysis. Two adjacent prepared maxillary molars were designed digitally. Two-unit splinted fixed dental prostheses (FDPs) were designed with 4 different triangular connector dimensions (2 × 3, 3 × 3, 3 × 4, and 4 × 4 mm (width × length)). The tested materials are Gold Metal, Base Metal Alloy, Feldspathic Porcelain, Lithium Disilicate, Zirconia, and Zirconia-Reinforced Lithium Silicate. A total of 56 two-unit splinted crowns models were designed and evaluated using finite element analysis (FEA) in Autodesk Fusion 360. FEA demonstrated a non-linear relationship between connector size and performance, with the 3 × 4 mm design exhibiting optimal stress distribution and the highest safety factor. Among different materials, the base metal alloy showed the highest safety factor across all configurations, while zirconia and lithium disilicate performed comparably under static loading. The 3 × 4 mm connector demonstrated optimal performance across all tested materials. Base metal alloy exhibited the highest safety factor among all connector dimensions.