In this review, we discuss the parameters of fused deposition modeling (FDM) technology used in finished parts made from polyether ether ketone (PEEK) and also the possibility of printing small PEEK parts. The published articles reporting on 3D printed PEEK implants were obtained using PubMed and search engines such as Google Scholar including references cited therein. The results indicate that although many have been experiments conducted on PEEK 3D printing, the consensus on a suitable printing parameter combination has not been reached and optimized parameters for printing worth pursuing. The printing of reproducible tiny-sized PEEK parts with high accuracy has proved to be possible in our experiments. Understanding the relationships among material properties, design parameters, and the ultimate performance of finished objects will be the basis for further improvement of the quality of 3D printed medical devices based on PEEK and to expand the polymers applications.

Achieving a strong bond between Polyetheretherketone (PEEK) and veneering composites is challenging due to PEEKs low surface energy. This study examined the effects of sandblasting and bonding on the shear bond strength (SBS) between veneering composite and pigmented PEEK, considering artificial aging. Of three pigmented PEEK compounds (DC4420R, DC4450R, DC4470R; Evonic Operations GmbH, Marl, Germany), 40 specimens each were milled and polished up to 2500 grit. Prior to veneering, specimens were divided into 4 subgroups: Subgroup 1: Polishing; 2: Polishing + bonding; 3: Sandblasting; 4: Sandblasting + bonding. Sandblasting was performed using Al₂O₃. Adhesive was an agent containing MMA (Signum Universal Bond, Kulzer GmbH, Hanau, Germany). After veneering (Composite, Kulzer GmbH) the subgroups were divided into 2 subgroups. One subgroup was immersed in 37 °C warm distilled water for 24 h. The second subgroup was artificially aged by thermocycling (TCL) with 5000 cycles in distilled water (5 °C / 55 °C; 30 s). Surface roughness, water contact angles and failure modes were recorded. SBS was measured using a universal testing machine. Results demonstrated that the combination of sandblasting and bonding significantly improved the SBS compared to polishing alone. PEEK color did not significantly influence the SBS. Aging by TCL had a negative effect on the SBS. Sandblasting and the use of an adhesive containing MMA were found to be effective in achieving satisfactory SBS between veneering composite and pigmented PEEK surfaces. These pretreatment methods demonstrate their potential for establishing durable and reliable bonding in clinical applications.