الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Provisional restorations play several roles during the implant integration period. Immediate provisionalization of implants at the time of placement can provide the patient with a tooth-like restoration. The purpose of this study was tostudy marginal adaptation, fracture resistance and cytotoxicityOf implant supported provisional restoration fabricated with different techniques.
Sixty master acrylic models were constructed, 30 of them had implant abutments with rounded shoulder finish line. and the other 30 had abutments prepared with chamfer finish line. Each group was subdivided into three subgroups according to the techniques of temporary crown fabrication. Resinous CAD/ CAM, Dual cure composite, and Conventional heat cure resin, Each sub group was subdivided into two divisions according to their surface finishing methods: Rubber points and Abrasive points.
To study cytotoxicity used. Sixty discs with 1mm thickness and 3mm diameter were fabricated using 3 different techniques, 2 different surface finishing methods.
The results of the study revealed that Resinous CAD/ CAM with chamfer finish line and finished by rubber point recorded significantly higher fracture resistance than other materials used in this study. Using round shoulder finish line significantly increased the marginal adaptation of implant prostheses.
The results revealed that crowns fabricated by CAD/CAM technique and finished with rubber points gave least toxicity to the cells while heat cured and rough surface provisional crown gave highest toxicity.
Within the limitations of this study the following conclusions can be drawn:
• Fabrication techniques and type of materials used for temporary crowns influenced the fracture resistance, marginal adaption and cytotoxicty of implant supported prosthesis.
• CAD/CAM implant supported provisional crown showed the highest fracture resistance and least marginal gap.
• The least marginal gap recorded with shoulder finish line.
• The finishing technique of CAD/CAM has direct effect in survival rate of cell line.
• The heat cure resin greatly interfere with survival of cell line