الفهرس 
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Abstract
Summary
The 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. It can also be a suitable material for fixed dental prosthesis (FDPs), due to its high resiliency. 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 between PEEK frameworks and veneering composite is essential to mask its grey colour. However, PEEK low surface energy and chemical inertness suggests a challenge to such bond.
Several studies proposed that the alteration of the PEEK surface with surface treatments and conditioning with an adhesive system enable a mechanical and chemical interaction between PEEK surface and veneering composite.
Objective: The aim of this study was to evaluate the effect of surface treatments on the surface roughness and shear bond strength of PEEK to veneering resin using two adhesives.
Methods: Sixty PEEK samples were randomly divided into three groups according to the preformed surface treatment modality into group (A): air abrasion, group (L): ER:YAG laser, group (C): control group (no surface treatment). Surface roughness after each surface treatment was then measured. Each group was then subdivided into two subgroups according to the adhesive system into Subgroup (V): visio.link and Subgroup (U): scotchbond universal adhesive. Bonding of the samples was done according to the manufacturer instruction. The shear bond strength was measured using a universal testing machine and failure mode assessed.
Results: for the surface roughness, there was a significant difference between the values of samples treated with different surface treatments with air abrasion samples had the highest value followed by samples treated with laser while the lowest value was found in control samples. As for shear bond, there was significant difference between different surface treatments and adhesives with the highest SBS values in samples bonded with Visio.link in the air abrasion group. For mode of failure analysis, the majority (77%) of all tested samples exhibited adhesive failures while 33% of all tested samples exhibited mixed failures mainly in the air abraded samples bonded with Visio.link.
Conclusion
On the basis of the results and conditions of this study, the following conclusions can be drawn:
1. Surface treatment affected the surface roughness of PEEK and air abrasion achieved the highest mean surface roughness value (Ra).
2. Surface treatment and choice of adhesive are essential for bonding between PEEK and veneering composite where air abrasion and MMA containing adhesives enhanced the shear bond strength between PEEK samples and veneering composite.