the effectiveness of adding a supporting implant in stress distribution of long span fixed partial denture (3d finite element analysis)

background and aim of study: long span is seen in many clinical situations, treatment planning options of these cases are difficult and may require: fpd, rpd or isp. each option has its own disadvantages: mechanical, patient relief and cost respectively. this article will evaluate the stress distribution of another treatment option which is adding a single supporting implant to the fpd by using 3d finite element analysis. materials and methods: three models, each consisting of 5units, were created as following: 1.tooth pontic pontic pontic tooth. 2.tooth pontic implant pontic tooth. 3.tooth pontic pontic implant tooth. an axial force was applied to the prostheses by using 3d finite element method and stress was evaluated. results: maximum stress was found in the prostheses in all models, highest stress values in all shared components of the models were close. stress in implants was less in the second model than the third one. conclusions: adding a supporting implant in long span fpd has no advantages while it has the disadvantages of complicating treatment and the complications that may occur to the implant and surrounding bone itself.