Computer-aided design and transverse strength of screw-retained attachments

Two commercially available, screw-retained attachments and an experimental attachment were modeled and analyzed by computerized finite element method. Mechanical test specimens were then developed. Cast rectangular bars were fabricated with the attachments or were joined by soldering at midspan as a control. These bars were subjected to three-point loading. The soldered connector was stronger than the three attachment designs, and the experimental attachment was stronger than the two commercial products. There was general agreement between the mechanical and finite element testing. The use of computer-aided technology to design dental devices with improved mechanical properties was demonstrated by this study.