Assessment of Recycled PETG as a Support Material for PLA-Based 3D Printed Anatomical Models

Three-dimensional (3D) printing technology provides the opportunity to reconstruct complex anatomical models with high accuracy. In the literature, it has been emphasized that the selection of support materials applied to three-dimensional models and the method of their removal after printing are decisive factors affecting both the production time and the integrity of the model. This study aimed to comparatively evaluate the effects of these two combinations on the printing process, support separation behavior and surface integrity by applying support structures from both the same material (PLA+PLA) and different material (PLA+recycled PETG) on model produced with polylactic acid (PLA) filament. In this study, five bone models (atlas, scapula, humerus, lumbar vertebrae, and ossa coxae) obtained from the same dog were produced in two different combinations to evaluate the compatibility of PLA and recycled PETG filaments: (1) PLA+PLA and (2) PLA+PETG. After printing, the support structures were manually removed, and comparative evaluations were performed in terms of surface deformation, ease of support removal, and printing time. Although the printing time was extended in the PLA+PETG combination due to filament transitions, it was observed that the supports were easily detached from the model surface, no surface deformation occurred, and the overall print quality was maintained. In contrast, in the PLA+PLA combination, detail loss and surface defects were detected during manual removal of the supports. As a result, it was concluded that the use of recycled PETG as a support material for the PLA main filament preserved the surface quality by reducing the risk of deformation on the model surface and could also be considered as an alternative support material.