Biomechanical behaviour of tooth-supported fixed partial dentures by 3D FEA.

This three-dimensional finite element analysis first described stresses distribution in loaded posterior fixed partial dentures, then compared the influences of bone height, abutment roots number and pontic length on their displacements. Twelve mandibular (three to five unit) FDPs integrating periodontal ligaments were designed. Stresses were localized in connectors and cervical areas of abutments near the edentulous span. The main FDPs' displacements consisted of vertical translation increasing with low bone height. FDPs underwent simultaneously an anteroposterior displacement (about ten times smaller) towards the weakest abutment side. Splinted abutments affected this anteroposterior displacement. Span length was associated with small beam deflection.