Mohammed Ghulam Mortada <br/><br/>
Effect of platform switching on stresses transmitted to implant supported fixed partial denture :   In-vitro study /  
 تاثير تغير صفيحة التشكيل على الحمال المنتقلة فى الاستعاضات السنية المثبتة المتكاة على غرسات :   دراسة معملة 
Mohammed Ghulam Mortada ; Supervised Ahmed Hassanien Khalil , Zeinab Nabil Emam 
 - Cairo :   Mohammed Ghulam Mortada ,   2016 
 - 83 P. :   charts , facsimiles , photoghrphs ;   25cm  
<br/><br/>Thesis (M.Sc.) - Cairo University - Faculty of Oral and Dental Medicine - Department of Prosthodontics 
<br/><br/> Statement of problem: Regarding implant placement and its exposure to the oral environment bone usually under-goes resorption and remodeling known as saucerization.The amount of bone resorption is one of the most deciding factors for the success of the dental implant.Stresses transmitted through the implant-abutment complex to the implant surrounding and supporting structures were claimed to the induce bone resorption. Increased transmitted stresses and exceeding the biological tolerance consequently affect the implant longevity and success. purpose: to evaluate the effect of platform switching when using implant supported fixed partial denture on the stresses transmitted to implant supporting structure and the fracture resistance of abutment fixed partial denture assembly material and methods: In vitro study performed using one implant system. Fixture platform diameter 4.7mm and two different abutment sizes, matching platform abutments 4.7mm diameter (group A) and platform switched abutments 3.5mm diameter (group B).Twenty implants were placed in epoxy resin cast, ten for each group and five porcelain fused to metal fixed prosthesis for each group. Both groups were subjected to 100 and 200 N using universal testing machine and strain gauges to measure strain. results: Under 100 & 200 N load; matching plat form abutments showed statistically significantly higher mean stresses induced at all axial surfaces of the implants than platform switched abutments. No significant difference in the fracture resistance of abutments fixed prosthesis assembly between both groups.conclusions: At 100N and 200N platform switching might decrease the amount of stresses transmitted to implant supporting structures and thus, decrease the crestal bone resorption around the fixture neck.The platform switching technique might have no effect on the fracture resistance of abutments and their corresponding fixed partial denture  
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<br/><br/><label>Subjects--Topical Terms: </label><br/>Dental implants
<br/><br/><label>Subjects--Index Terms: </label>Implant supported fixed partial denture  Platform switching  Stresses transmitted