XFEM fracture modelling for implant-supported fixed partial dentures

The dental implants have been increasingly used for replacing missing teeth over the past three decades. However, its mechanical strength remains a major concern to dental clinicians and patients. To investigate failure modes and fracture loads of implant-supported fixed partial bridge, eXtended Finite Element Method (XFEM) was employed in this study. The 3D finite element (FE) models simulating full mandibular teeth and implant-supported three-unit fixed partial denture (FPD) were developed to determine the crack initiation and propagation in the dental prostheses. The failure modes and fracture loads are compared for three typical treatment scenarios: namely three-unit FPD supported by two implants at left second premolar and first molar (named as cantilever Model-IIP), second premolar and second molar (bridge Model-IPI), and first and second molars (cantilever Model-PII). The XFEM analyses show that the bridge Model-IPI exhibited considerably high fracture resistance than the other two configurations. Model-IIP displays the worst fracture strength of these three case scenarios. The results provide a basis for clinical assessment of mechanical strength for implant-supported FPD or other restorative devices.