Abstract
Objective The interest in using 3D printing in the healthcare field has grown over the years,
given its advantages and potential in the rapid manufacturing of personalized devices
and implants with complex geometries. Thus, the aim of the present study was to compare
the mechanical fixation behavior of a 3D-printed interference screw, produced by fused
deposition modeling of polylactic acid (PLA) filament, with that of a titanium interference
screw.
Methods Eight deep flexor porcine tendons, approximately 8 mm wide and 9 cm long, were used
as graft and fixed to a 40 pounds-per-cubic-foot (PCF) polyurethane block at each
of its extremities. One group was fixed only with titanium interference screws (group
1) and the other only with 3D-printed PLA screws (BR 20 2021 018283-6 U2) (group 2).
The tests were conducted using an EMIC DL 10000 electromechanical universal testing
machine in axial traction mode.
Results Group 1 (titanium) obtained peak force of 200 ± 7 N, with mean graft deformation
of 8 ± 2 mm, and group 2 (PLA) obtained peak force of 300 ± 30 N, and mean graft deformation
of 7 ± 3 mm. Both the titanium and PLA screws provided good graft fixation in the
polyurethane block, with no slippage or apparent deformation. In all the samples,
the test culminated in graft rupture, with around 20 mm of deformation in relation
to the initial length.
Conclusion The 3D-printed PLA screw provided good fixation, similar to that of its titanium
counterpart, producing satisfactory and promising results.
Keywords bone screws - lactic acid - printing, three-dimensional
