Polydopamine-functionalized PEEK/PTFE composites with enhanced tribological, photothermal antibacterial, and mechanical properties for TMJ disc repair

The temporomandibular joint disc (TMJD) lacks intrinsic regenerative capacity, and to date, no effective or durable clinical treatments exist for its repair, presenting a major challenge in medical practice. In this study, a facile strategy has been developed to fabricate poly(ether-ether-ketone) (PEEK)/polytetrafluoroethylene (PTFE)@ polydopamine (PDA) composites with good biocompatibility and wear-resistant properties for TMJD replacement and repair. Biocompatible PDA molecules are introduced to improve interfacial affinity between PEEK and PTFE molecules. The results show that the mechanical properties of as-prepared PEEK/PTFE@PDA composite are adjusted to be close to those of TMJD. The tensile strength, compressive strength, and flexural strength of PEEK/PTFE@PDA composite are 73.63 ± 0.69 MPa, 63.28 ± 15.83 MPa, and 81.10 ± 3.80 MPa, respectively. Furthermore, the friction coefficient and wear rate of PEEK/PTFE@PDA composite are 0.041 and 3.54 × 10 -7 mm³/Nm, which are reduced by 81.4% and 42.7% than those of PEEK, respectively. The antibacterial rates of PEEK/PTFE@PDA composite against Gram-positive bacteria ( Staphylococcus aureus ) and Gram-negative bacteria ( Escherichia coli ) is 99.6 ± 0.1% and 92.5 ± 0.2% under near-infrared laser irradiation, respectively. This study paves the way for the application of PEEK-based composites in maxillofacial implants and provides a new strategy for solving temporomandibular joint disorder.