الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The novel high performance composite polyetheretherketone (PEEK), is a polymer from the main group of PAEK (polyaryletherketone).
Since PEEK has many advantages in its physical, biological and mechanical properties, this composite material is used in general medicine and also in dentistry, which can be used as implant, provisional abutment and implant supported bar or clamp material.[100] It can also be a suitable material for fixed dental prostheses (FDPs), due to its high resiliency.[3] It also has a high strength to weight ratio which make it more favourable for the patients, mechanically it is similar to bone and dentin properties, in addition to its zero-corrosion rate and extremely low water absorption.
Successful long-term bond strength to any indirect prosthetic material is influenced by a variety of factors during the bonding procedures. Contamination inhibits the formation of a stable bond [61, 65] by reducing the adaptation of the restorative material to the bonded surface.[4] Therefore, clean bonding substrates and materials are essential to achieve stable long-term bond strength. Since bonding to ceramics, zirconia and resins can be compromised by contamination during try in procedure or during fabrication in the dental laboratory. Saliva, blood, silicone indicator, and die stone have been identified to reduce bond strength of resins to restorations and dental hard tissue.[5, 66]
Objective. Aim of this study was to evaluate the effect of different contamination on the tensile bond strength of PEEK with resin cement.
Methods. 80 PEEK cylinders were milled having the final dimension of (12x12), these specimens were divided into 4 groups according to the contamination method, temporary cement, artificial saliva, fit checker and a control group with no contamination. Furthermore, the 3 first groups were subsequently subdivided into 3 subgroups according to the cleaning method, ultrasonic cleaner, phosphoric acid and Ivoclean. Bonding of the specimens was done according to the manufacturer instruction. The tensile bond strength of the different groups and subgroups was then measured using the universal testing machine.
Results. No significant difference was found between the control group and the group contaminated using saliva. No significant differences were found between the different contamination methods; however, statistically significant difference was found between temporary cement and fit checker contamination and the control group. As for the cleaning methods, statistically significant difference was found between the three cleaning methods and between them and the control group.
Conclusion
On the basis of the results and conditions of this study, the following conclusions can be drawn:
• Temporary cement and fit checker adversely affected the tensile bond strength of PEEK more than the saliva.
• The ultrasonic cleaner effectively cleans the contaminants from PEEK surface and enhanced the tensile bond strength after contamination.