Department of Small Animal Emergency and Critical Care, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
Department of Clinical Science, Intervention and Technology, Division of Imaging and Technology, Karolinska Institute, Huddinge, Sweden.
Biomed Mater. 2023 Mar 28;18(3). doi: 10.1088/1748-605X/acc55e.
In this proof-of-concept, bone neoformation beyond the skeletal envelope is explored by using a collagen pouch (= 6) packed with calcium phosphate (CaP) granules placed over the frontal bone in sheep (= 3). At 13 weeks, macroscopic examination showed specimens covered by an adherent fibrinous envelope with slight vascularization. Histology revealed colonization of the implant by newly formed woven bone and fibrous connective tissue. Surface osteoblasts as well as material-filled macrophages, lymphocytes, polymorphonuclear cells and giant cells were also found in large quantities surrounding the newly formed bone tissue inside the collagen pouch. On the side facing the recipient bone, the collagen membrane had to a large extent been resorbed and bridging bone formation was clearly visible between the test article and recipient bone. On the other side facing soft tissue, the collagen pouch remained intact with a visible fibrous capsule. This study demonstrated that the use of a collagen sleeve as a container for CaP granules allows for good neoformation beyond the skeletal envelope with bridging bone formation clearly visible between the test article and recipient bone. Additionally, in this model, macrophages rather than osteoclasts appear to modulate CaP granule resorption and remodeling into new bone. This construct opens new perspectives for treatment methods that could be used for bone augmentation and restoration of cranio-maxillofacial defects and malformations.
在本概念验证研究中，通过使用胶原套（= 6）填充钙磷（CaP）颗粒，将其放置在绵羊（= 3）额骨上，探索了骨骼包膜外的新骨形成。在 13 周时，宏观检查显示标本被附着的纤维性包膜覆盖，有轻微的血管化。组织学显示植入物被新形成的编织骨和纤维结缔组织所殖民。在胶原套内部新形成的骨组织周围，还发现了大量的表面成骨细胞以及充满材料的巨噬细胞、淋巴细胞、多形核细胞和巨细胞。在朝向受体骨的一侧，胶原膜已在很大程度上被吸收，并且在测试物和受体骨之间可以清楚地看到桥接骨形成。在另一侧面向软组织，胶原套保持完整，有可见的纤维囊。这项研究表明，使用胶原套管作为 CaP 颗粒的容器，允许在骨骼包膜外进行良好的新骨形成，并且在测试物和受体骨之间可以清楚地看到桥接骨形成。此外，在该模型中，似乎是巨噬细胞而不是破骨细胞调节 CaP 颗粒的吸收和重塑为新骨。这种构建体为治疗方法开辟了新的前景，可用于骨增强和修复颅面缺损和畸形。
