The Analysis Of The Finite Element-aid Design Of Fixed Bridge Supported By Implants In Restoring The Single Side Distal Free-end Edentulism

Objective:To develop a new kind of Fixed Bridge Supported by Implants in Restoring the single side distal Free-end Edentulism which could be supported by implants and has more reasonable structure and funtction.By construct a 3-D finite element model for this design,to get more proper design proposal through getting the stress distribution of bone around the implant when bridge length is change and getting the stress distribution of attachment body when areas are changed.Methods:This research is composed by three experiments.1.Experimentâ… :Choose a maxillary bone,take ATOS scanning for it,then scanning the coping crown of promolar and molar.According to different implant place,construct two different models:Modelâ… and Modelâ…¡.Combining ATOS scanning,digital image transfer and a series of computer software to construct the finite element model of the Implants of Fixed Bridge.2.Experimentâ…¡:According to designed three different cross section areas of attachment body,the Modelâ… could be zoomed into thress classification model: Modelâ… -â… (cross section area is 3mm~2),Modelâ… -â…¡(cross section area is 4mm~2), Modelâ… -â…¢(cross section area is 5 mm~2),Modelâ…¡-â… (cross section area is 7mm~2), Modelâ…¡-â…¡(cross section area is 8mm~2),Modelâ…¡-â…¢(cross section area is 9mm~2). Choose same force load mode on long axis of coping crown and implant,and get deflection of attactment body less than or equal to 0.001mm through computer software.3.Experimentâ…¢:According to Modelâ… and Modelâ…¡,get maximum stress value of bone around implant and attachment through same force load mode,analyze the rule of stress variation through comparing the date mentioned above.Results:1.Successfully construct a 3-DFEM which has good geometric similarity.The implant in the model could be observed within the jaw or separately abstracted from the jaw by any angle or any way,and it could be modified for different investigation purpose.2.In the analysis with different bridge length,the maximum stress is concentrate on the attachment body which has maximum deformation.In Modelâ… ,deflections are 0.00106,0.000938 and 0.000563mm.In Modelâ…¡,deflections are 0.00118,0.000958 and 0.000785mm.3.The maximus stress is concentrate on the bone around the implant.Bridge length will have certain impact on stress distribution of bone around the implant,but the cross section areas of attachment body will not have certain impact on stress distribution of bone around the implant.The stress value of the cross section area will diminish with the increase of the cross section area of bridge.Modelâ… and Modelâ…¡,the stress value of mesio-attachment body will higher than disto-attachment body.Conclusion:The method of combining ATOS and a series of computer software to construct a 3-D finite element model of Fixed Bridge Supported by Implant in Restoring in single side distal Free-end Edentulism is feasible and effective.From the view of biomechanics,in the same foece load mode,bridge length will have certain impact on stress distribution of bone around the implant,but the cross section areas will have certain impact on stress distribution of the cross section of attachment body.So it should diminish bridge length and increase cross section area.In Modelâ… and Modelâ…¡,the cross section areas of the attachment body should be more than or equal to 4mm~2 and 8mm~2,and strains are less than or equal to 0.1%.