Uwe Y. Schwarze^1,2,*; Valentin Herber^1,2; Muammer Ücal³; David Hahn²; Omer Suljevic¹; Michael Payer²; Annelie Weinberg¹; Nicole G. Sommer¹

¹Department of Orthopaedics and Trauma; ²Division of Oral Surgery and Orthodontics; ³Department of Neurosurgery, Medical University of Graz, Graz, Austria

Background: In implant dentistry and orthopaedics availability and regeneration of bone are crucial topics. Therefore, a major focus is to maximize healing and reduction of complications by guiding scaffolds. Challenges can be for example compromised healing by underlying pathologies and age. 3D printing customized biomaterials can counteract these challenges with increased time efficiency, decreased complication risks, and enhanced healing capabilities.

Aim/Hypothesis: In this study we evaluated biocompatibility and osteoconductivity of a novel biodegradable 3D printed β-TCP (LithaBone TCP 380 D, Lithoz GmbH, Austria, Vienna) scaffold in proximal tibia and calvaria of rats, for its possible use in guided bone regeneration in oral surgery and orthopaedics.

Material and Methods: In 36 (n = 12 for each group) adult male Sprague Dawley rats bilateral calvaria defects (Ø 5 mm) together with mono cortical proximal tibia defects (Ø 1.5 mm, depth: 6 mm) were applied. Defects on the left side were left untreated as sham control, whilst the right side were filled with one of the following bone substitutes: 1) a novel biodegradable 3D printed β-TCP (LithaBone TCP 380 D) by Lithoz, 2) a proven 3D printed β-TCP (LithaBone TCP 300) by Lithoz, and 3) Bio-Oss®Block by Geistlich Pharma AG (Wilusan, Switzerland). To evaluate dynamic bone formation, the fluorochromes Calcein and Xylenol orange were administered via intraperitoneal injection at week 2 and 3. In vivo micro-CT scans at week 2 and 4 and an ex vivo scans post-mortem were used to analyze bone volume in the defect area and scaffold volume. Histological undecalcified thin ground sections will be used to assess biocompatibility, newly formed bone area, penetration depth, vessel number, vessel area and bone apposition rate.

Results: Preliminary results of qualitative analyses showed a remarkable biocompatibility and osteoconductive properties with almost full calvaria scaffold penetration after 4 weeks compared to the sham side. Quantitative results are pending and are expected to be ready for the congress.

Conclusion and Clinical implications: In case of confirmation of the qualitative results biodegradable 3D printed β-TCP scaffold could be a candidate for guided bone regeneration in alveolar regions to facilitate implant placement and in orthopaedics, traumatology and neuro surgery to promote bone regeneration in flat and long bone defects.

Disclosure of Interest: None Declared

Keywords: all-ceramic, bioprinting, bone regeneration

乌维 Y.施瓦兹^1,2,* ; 瓦伦丁·赫伯^1,2 ; Muammer Ücal ³ ; 大卫·哈恩² ; 奥马尔·苏列维奇¹ ; 迈克尔·佩耶² ; 安妮莉温伯格¹ ; 妮可 G. 萨默¹

¹骨科和创伤科；²口腔外科正畸科；³神经外科，格拉茨医科大学，奥地利格拉茨

背景：在种植牙和骨科中，骨骼的可用性和再生是至关重要的主题。因此，主要关注点是通过引导支架最大限度地愈合和减少并发症。例如，潜在的病理和年龄可能会影响愈合。3D 打印定制生物材料可以通过提高时间效率、降低并发症风险和增强愈合能力来应对这些挑战。

目的/假设：在这项研究中，我们评估了一种新型可生物降解 3D 打印 β-TCP（LithaBone TCP 380 D，Lithoz GmbH，Austria，Vienna）支架在大鼠胫骨和颅骨近端的生物相容性和骨传导性，因为它可能用于引导骨口腔外科和骨科再生。

材料和方法：在 36 只（每组n = 12）成年雄性 Sprague Dawley 大鼠中应用双侧颅骨缺损（Ø 5 mm）和单皮质近端胫骨缺损（Ø 1.5 mm，深度：6 mm）。左侧的缺陷未经处理作为假对照，而右侧则填充了以下骨替代品之一：1) Lithoz 的新型可生物降解 3D 打印 β-TCP (LithaBone TCP 380 D)，2) 经验证的 3D Lithoz 印刷的 β-TCP（LithaBone TCP 300），和 3）Geistlich Pharma AG（瑞士威卢桑）的 Bio-Oss®Block。为了评估动态骨形成，在第 2 周和第 3 周通过腹膜内注射施用荧光色素钙黄绿素和二甲酚橙。在第 2周和第 4 周进行体内显微 CT 扫描以及离体死后扫描用于分析缺损区域的骨量和支架体积。组织学未脱钙的薄地面切片将用于评估生物相容性、新形成的骨面积、穿透深度、血管数量、血管面积和骨并列率。

结果：定性分析的初步结果显示，与假侧相比，4 周后具有显着的生物相容性和骨传导特性，几乎完全穿透颅骨支架。定量结果正在等待中，预计将为大会做好准备。

结论和临床意义：在确认定性结果的情况下，可生物降解的 3D 打印 β-TCP 支架可能是牙槽区引导骨再生的候选者，以促进植入物的放置，以及在骨科、创伤学和神经外科手术中促进扁平和骨再生。长骨缺损。

利益披露：无申报

关键词: 全瓷, 生物打印, 骨再生