Determination of bacterial load on real bone and 3D printing bone models used in veterinary anatomy education

In veterinary anatomy education, real bones used for instructional purposes often develop problems over time, including wear, odor, and mold. In recent years, educational materials have been produced using 3D printing technologies with different filaments such as PLA, PETG, ABS, and TPU. No information in the literature addresses the hygiene-related advantages or disadvantages of real bone compared with produced prints in the laboratory. The aim of this study was to demonstrate the health suitability of 3D bone models produced using standard PLA and antibacterial PLA, and of educational models consisting of real bone. In this study, a total of 15 models (five of each) were examined and sterilized using formaldehyde fumigation. All models were used in the student laboratory for three months. At the end of this period, subsamples were taken from each sample to determine aerobic mesophilic bacterial loads. Among the real bones, the highest bacterial loads were found in the axis and the cranium. Bacterial loads were similar in the scapula, humerus, and femur and in models of these bones fabricated from standard PLA. No bacteria were isolated from any of the antibacterial PLA models. As a result, it was observed that antibacterial PLA was the most hygienic model under laboratory conditions, that sterilization by formaldehyde fumigation effectively eliminated bacteria, and that it did not cause any visible deformation or discoloration of the filaments.