Optimization of Material and Printing Parameter Selection for FDM 3D-Printed Bone Models for Osteotomy Training: A Biomechanical and User-Based Evaluation

Although additive manufacturing enables cost-effective surgical training models, variation in materials and printing parameters limits standardization. This study combined biomechanical testing and user evaluation to identify fused deposition modeling (FDM) settings for osteotomy simulation. Porcine ribs and three-dimensional (3D)-printed models were compared using three-point bending tests. Subsequently, 32 participants performed osteotomies using an ultrasonic device, a Lindemann bur, and a reciprocating saw. Haptic feedback was assessed by questionnaire, while surface artifacts were evaluated by two blinded evaluators. With 25% gyroid infill and two outer layers, maximum bending forces ranged from 322.9 to 552.1 N across the printed materials, compared with 604.9 N for the porcine ribs, with polylactic acid (PLA) showing the closest approximation. Polycarbonate (PC) achieved the highest haptic rating (6.7 ± 1.8), followed by acrylonitrile styrene acrylate (ASA), polyethylene terephthalate glycol (PETG), and PLA, with a significant difference between PC and PLA (p = 0.029). The reciprocating saw received the highest ratings across all criteria. Surface artifacts differed between materials (p < 0.001), with PETG and PLA showing more melting and fraying, and ASA and PC more stringing. No significant differences were observed between students and doctors. Overall, PLA most closely approximated the reference maximum bending force, whereas PC and ASA achieved the highest perceived tactile realism.