Antimicrobial Biodegradable Bone Graft for Craniofacial/Maxillofacial Application

描述（由申请人提供）：与以前的军事冲突相比，在伊拉克和阿富汗的战斗行动中，创伤性面部损伤相对于其他解剖部位损伤的发生率急剧上升。即使在平民人群中，创伤性颅面骨损伤也常伴有周围软组织的损伤或丢失。有报告称，面部遭受枪伤的平民的局部并发症和伤口感染率高达100%。在涉及骨缺损的开放性骨折的情况下，外科医生必须找到一种方法来快速修复伤口，同时降低慢性感染或骨髓炎的风险。在I期项目中，我们建议开发一种上级局部抗生素递送系统（以珠粒形式），该系统还具有可吸收性和骨诱导性。这些珠子将由可生物降解的镁制成。微珠将被羟基磷灰石（HA）和庆大霉素包被。HA涂层将使用Spire的商业TPA工艺进行涂覆，该工艺在低温下产生薄（5-10 μ m）层，从而保留HA源材料的原始化学成分和相。众所周知，HA可以启动和加速骨生长。我们提出了一个系统，其中HA将启动骨生长;随着HA开始缓慢溶解，Mg也将降解，从而使抗生素局部分布，防止感染。最重要的是，不需要进行后续手术来从该部位移除任何植入物或珠。

DESCRIPTION (provided by applicant): The incidence of traumatic facial injuries relative to injuries at the other anatomic locations has risen sharply during combat operations in Iraq and Afghanistan compared to previous military conflicts. Evan in the civilian population, traumatic craniofacial bone injury is often accompanied by injury or loss of surrounding soft tissues. There are reports of local complications and wound infection rates as high as 100% in civilians suffering gunshot wounds to the face. In the cases of open fractures that involve bone defects, the surgeon must find a way to quickly repair the wound while reducing the risk of chronic infection or osteomyelitis. In the Phase I program, we propose to develop a superior local antibiotic delivery system (in the form of beads) that also possesses resorbable and osteoinductive properties. The beads would be made of biodegradable magnesium. The beads will be coated with hydroxyapatite (HA) incorporated with gentamycin. The HA coating will be applied using Spire's commercial TPA process which produces a thin (5-10¿m) layer at a low temperature, thereby retaining the original chemical composition and phase of the HA source material. HA is well-known to initiate and expedite bone growth. We propose a system in which the HA will initiate bone growth; as the HA starts to dissolute slowly, the Mg will also degrade allowing the antibiotic to be distributed locally, preventing infection. Most importantly, there wil be no need for a subsequent operation to remove any implant or bead from the site.