Background/purpose: A fiber-reinforced composite (FRC) resin system was introduced
as an alternative for implant-retained fixed dental prostheses (FDPs); however, the
stress distribution in the bone around the implants which support the FRC-FDP has so far not
been reported. The aim of this study was to investigate the biomechanical behavior of FRCFDPs
supported by implants with different collar geometries.
Materials and methods: A 3-dimensional finite element analysis method was selected to evaluate
the stress distribution. FRC-FDPs were supported by 2 different dental implant systems with
2 distinct collar geometries: a microthread collar structure (MCS) and a non-MCS (NMCS). In separate
load cases, 300-N vertical, 150-N oblique, and 60-N horizontal forces were simulated. Tensile
and compressive stress values in the cortical and cancellous bone and von Mises stresses in the
fixture-abutment complex, the framework, and veneer material were calculated.
Results: TheMCS model revealed higher compression stresses at the cortical bone than did theNMCS
model under all 3 load conditions. Moreover, higher tensile stresses under the oblique loads at the
cortical bone were shown with the MCS model. In eachmodel, stresses were much higher in the implanteabutment
complex than in the cortical bone, and they were very low in the cancellous bone.
Conclusion: Although additional experimental and clinical studies are needed, FRC-FDPs can be
considered a suitable and alternative treatment choice for an implant-supported prosthesis. The
implant design and geometry affect the load-transmission mechanisms.