Volume 3, Issue 3 (March 2006)
Radio Frequency Plasma Treatment of PEEK Spinal Implants
Recent material developments have enabled metallic vertebral spacers to be redesigned from a biocompatible radiolucent polymer to allow clear X-Ray or MR assessment of bony fusion. Improved visualization response is considered a major clinical advantage during the post-operative recovery period. The use of implant quality polyetheretherketone (PEEK) polymer for the fabrication of radiolucent vertebral spacers poses a new set of material challenges. Traditional manufacturing methods associated with metallic implants are generally not satisfactory for polymeric materials. Polymers are relatively soft when compared to implant alloys and this can create manufacturing problems related to machining, deburring, and cleaning operations. The present study was performed to evaluate the use of radio frequency (RF) plasma treatment as a final surface modification for PEEK spinal implants. A brief description of the radio frequency plasma process is presented in addition to a discussion of the interaction between the gas plasma and substrate. Surface evaluation included goniometry testing to determine water contact angle before and after plasma treatment. X-ray photon spectroscopy analysis was used to characterize the elemental peaks, bond energies, and to define the semi-quantitative composition of the treated implant specimens. The relative advantages of plasma treatment are summarized.