Experimental and numerical evaluation of the retention force for metallic matrix attachment systems

Oral implants and attachment systems represent an easy solution for preventing vertical displacement of removable dentures. Retention force is the most important operational parameter for an attachment system. Starting from the design phase it´s possible to test different designs and evaluate mechanical retention with relatively low costs using numerical simulation. In this study, a methodology was proposed for evaluation of retention force using numerical simulation. In order to validate the methodology, simulated results were compared with experimental reference data obtained in the same conditions. The magnitude of the retention force for the spherical blunt - metallic matrix attachment system produced by Straumann was determined using a specially designed experimental setup. Qualitative and quantitative analysis demonstrated that numerical model is stable and predicts correctly the retention force. Uncertainties led to acceptable deviations from experimental values.