Three-dimensional finite element analysis of two kinds of extracoronal attachments in a new design to restore maxillary edentulous jaw

Objective: To choose a kind of more reasonable attachment by comparing three-dimensional finite element stresses of two kinds of attachments in anterior implant fixed bridge and posterior extracoronal at- tachment denture to restore maxillary edentulous jaw. Materials and Methods: The three-dimensional finite element model of extracoronal resilient attachment model (model I) was reconstructed which had a good similarity. By modifying part model, extracoronal rigid attachment model (model II) was established. Static loading direction was 30 o diagonal and vertical to buccal inclined surface of lingual cusp of the first molar. The load force was 300N and load place was buccal inclined surface of lingual cusp of the first molar. The results of stresses were analysed by MSC software. Results: The stress of model II was significant higher than model I in four implans, anterior teeth and attachments. Otherwise, the stress of model II in palatal bars and posterior teeth was similar to model I. Conclusion: Choosing extracoronal resilient attachment is better in the design of anterior implant fixed bridge and posterior extracoronal attachment denture to restore maxillary edentulous jaw in oral biomechanics.