Polylactic acid (PLA) composite filaments with varying concentrations of bismuth oxide microparticle additives were fabricated for use with commercially available fused filament fabrication (FFF) printing systems for the production of spine phantoms that mimic the radiopacity of bone. Thermal analysis showed that the additives had limited impact on the glass transition temperature and melting point of the filaments, allowing for their use in commercial FFF systems with standard printer settings. The ultimate strength of the printed test specimens was found to reduce slightly when bismuth oxide was added in high concentrations, with a moderate reduction of 12% compared to PLA at the highest concentration of 30 wt%. The modulus of the specimens increased by up to 24% with the addition of the additive. The radiopacity of specimens printed with the composite filaments were measured by X‐ray microcomputed tomography (micro‐CT) and clinical computed tomography (CT). The CT number was found to increase by approximately 196 HU per wt% of bismuth oxide added to the filaments. A phantom model of a cervical spine deformity was successfully printed by FFF with a composite filament which was calibrated to mimic the radiopacity of cervical and cortical bone. The results indicate that the composite filaments have direct applicability for the production of phantoms used for education and preoperative planning.

中文翻译：

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用于放射模拟计算机断层扫描脊柱模型的 3D 打印氧化铋-聚乳酸复合材料

制造了具有不同浓度氧化铋微粒添加剂的聚乳酸 (PLA) 复合长丝，用于与市售的熔丝制造 (FFF) 打印系统一起使用，以生产模拟骨骼不透射线的脊柱模型。热分析表明，添加剂对长丝的玻璃化转变温度和熔点的影响有限，允许它们在具有标准打印机设置的商业 FFF 系统中使用。发现当添加高浓度氧化铋时，印刷试样的极限强度略有降低，与最高浓度 30 wt% 的 PLA 相比，适度降低了 12%。加入添加剂后，试样的模量增加了 24%。通过 X 射线微计算机断层扫描 (micro-CT) 和临床计算机断层扫描 (CT) 测量印有复合细丝的标本的射线不透性。发现每添加到长丝中的氧化铋 wt%，CT 值增加约 196 HU。FFF 成功打印了颈椎畸形的体模模型，该模型使用复合材料丝进行了校准，以模拟颈椎和皮质骨的射线不透性。结果表明，复合长丝可直接用于生产用于教育和术前计划的体模。FFF 成功打印了颈椎畸形的体模模型，该模型使用复合材料丝进行了校准，以模拟颈椎和皮质骨的射线不透性。结果表明，复合长丝可直接用于生产用于教育和术前计划的体模。FFF 成功打印了颈椎畸形的体模模型，该模型使用复合材料丝进行了校准，以模拟颈椎和皮质骨的射线不透性。结果表明，复合长丝可直接用于生产用于教育和术前计划的体模。