Photoelastic stress analysis surrounding different implant designs under simulated static loading.

OBJECTIVE: The proposal of this study was to use a photoelasticity method to analyze the stress dissipation in the bone surrounding an implant under simulated loading. MATERIALS AND METHODS: Four implant systems with different internal connection designs were studied: conical connection (group 1), triangular connection (group 2), Morse taper (group 3), and internal hexagon (group 4). After the models' inclusion in a photoelastic resin, they were subjected to static loads of 100, 150, and 200 N. The lengths of fringes that were generated were measured at the bone crest parallel to the neck of the implant and along the implant body, as well as the dissipation of force across the entire area of extension. RESULTS: Lower stress was observed at the crestal bone in groups 1 and 3 with no significant increase (P < 0.05) in different levels of load, whereas the stress levels in groups 2 and 4 were observed to be higher with loads of all intensities with significant differences from the other groups (P < 0.05). CONCLUSIONS: The type of connection and the implant neck design influenced the dissipation of force. The conical-type connection exhibited better load dissipation in the neck area, regardless of the load applied on the implant.