A new biocompatible biomaterial : PEEK / β-TCP / TiO2 composite

Introduction : Polyetheretherketone (PEEK) is an aromatic, rigid semi-crystalline thermoplastic with excellent mechanical properties and bone-like stiffness, and good biocompatibility [1-2]. Moreover for biomedical applications, particularly in the area of load-bearing orthopaedic applications [3] PEEK is able to be repeatedly sterilized, and shaped by machining or injection moulding. Devices utilising PEEK’s unique combination of properties have found considerable success in spine, cardiovascular and dental applications. PEEK composites were developed such as fiber renforced PEEK composites for bone plates [4], or PEEK-HA composites as a possible bone analogue substitute for load-bearing functions [5-6] or as scaffold for bone tissue engineering [7]. An innovant PEEK based composite has been produced consisting of a dispersion of β-tricalcium phosphate (β-TCP) (10 % w/v) and Titanium oxide (anatase) (10 % w/v) throughout a PEEK matrix. The PEEK/β-TCP/TiO2 demonstrated excellent mechanical properties, with elastic modulus comparable to that of natural cortical bone : tensile strength of 98 MPa, flexural modulus of 4.7 GPa and a flexural strength of 16MPa. Moreover based on the recommendations of ISO 10993 “Biological evaluation of medical devices” (2004) cytotoxicity, acute systemic toxicity, irritation, sensitization, mutagenicity (Ames test, chromosome aberrations using human lymphocytes, sister chromatid exchange) were performed and demonstrated composite biocompatibility. In this study we have investigated the cytocompatibility and bioactive nature of the material using human osteoblasts.