Fabrication of Rigid Polyurethane Foam Lumbar Spine Model for Surgical Training using Indirect Additive Manufacturing

Lumbar model is an artificial bone that commonly used in surgical training to simulate working with the human-like for trainer. The common lumbar made of rigid polyurethane (PU) foam and produced using casting. However, current expensive has limitations representing real human lumbar, especially geometry, visuals, haptics. Therefore, alternative method fabricating models indirect additive manufacturing will be investigated this paper. proposed a combination 3D printing casting methods. main process started by mold polyvinyl alcohol (PVA) fused deposition modeling (FDM) subsequently PU material into printed PVA mold. Accordingly, aim study find optimized parameters, injecting mold, achieve better quality model. was conducted Design Experiment (DoE) Taguchi Orthogonal Array optimize process. geometrical measurements middle end-plate depth, upper width, spinal canal lower pedicle length show error ranged from 0.14% 0.85%. average porosity, measured body, lamina, spinous, found non-uniform. It 19.58% 21.94% on part 39.78% 45.41% subsurface density increased 64.89% compared reference open molded foam.