3D-Printed Antibacterial Prostheses.

INTRODUCTION Previous investigations (Godymchuk, et al., 2015; Palza, 2015) have shown that copper compounds have a high potential for the development of medical devices with powerful antibacterial properties at a very low cost. The addition of copper nanoparticles to polymers has shown strong antimicrobial properties producing novel biocide materials and allowing for the development of a broad range of polymer nanocomposites with a high release of metal ions facilitating the antimicrobial properties (Palza, 2015). It has been suggested (Palza, 2015) that the addition of copper nanoparticles to polymers and the resulting antimicrobial properties have promising applications in the development of medical devices associated with bacterial development, such as socket-based prostheses. Therefore, the purpose of the present investigation was twofold: (1) describe the development of 3D-printed prostheses using antibacterial filament, and (2) verify the antibacterial properties of the 3D-printed prostheses. Based on previous investigations (Godymchuk, et al.; 2015; Palza, 2015), we hypothesized that (1) antibacterial 3D-printed filament can be used for the development of functional upper-limb prostheses, and (2) the antibacterial properties of the 3D-printing filament after extrusion and development of the prosthesis will not affect the antibacterial properties of the filament. METHOD Two adult males (65 and 40 years of age) with left index finger amputations at the proximal phalanx were fitted with a customized 3D-printed finger prosthesis manufactured with antibacterial filament. Using a desktop fused deposition modeling 3D printer, partial finger prostheses were manufactured using PLACTIVE 3D-printing filament. PLACTIVE is a polylactic acid polymer containing copper nanoparticles. Bacterial analysis of the 3D-printed prostheses was performed by an independent laboratory against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) (ISO 22196). Manual gross dexterity was assessed using the Box and Block Test. Patient satisfaction was assessed using the Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST 2.0). RESULTS Two customized 3D-printed partial-finger prostheses were manufactured using 3D-printed antibacterial filament. The bacterial analysis showed that PLACTIVE with 1% antibacterial nanoparticles additives was 98.91% effective against S. aureus and 95.03% effective against E. coli after a 24-hour incubation period. Manual gross dexterity improved for both patients after using the 3D-printed partial-finger prosthesis (subject 1 without prosthesis: 17.7 ± 0.6; subject with prosthesis: 22.3 ± 1.5 blocks per minute; subject 2 without prosthesis: 21.0 ± 1.0; subject 2 with prosthesis: 32.3 ± 2.5 blocks per minute). The research subjects rated their satisfaction with the 3D-printed partial-finger prostheses as “quite satisfied” to “very satisfied” (subject 1 = 4.8 ± 0.28 and subject 2 = 4.6 ± 0.3). DISCUSSION The main findings of the current investigation were that the antibacterial 3D-printed filament, PLACTIVE, can be effectively used for the development of functional 3D-printed finger prostheses. Furthermore, the antibacterial properties of the 3D-printing filament after extrusion were not affected. The thermoforming properties of polylactic acid were not affected by the addition of copper nanoparticles and allowed for post-processing modifications necessary for the final fitting of the 3D-printed antibacterial finger prostheses. CONCLUSION The unprecedented accessibility of 3D-printing technology and the development of 3D-printing filament with antibacterial properties has several medical applications and has the potential to revolutionize the manufacturing of medical devices. [ABSTRACT FROM AUTHOR]