Antimicrobial Biodegradable Bone Graft for Craniofacial/Maxillofacial Application

项目摘要 镁（Mg）及其合金已经吸引了越来越多的兴趣用作可生物降解的植入物，例如 骨科和颅颌面外科手术的固定器械，由于其有前途的机械和 生物学特性，以及它们在体内降解和再吸收的能力。第二阶段的总体目标 计划是延长令人鼓舞的第一阶段的结果，其中可生物降解的镁珠，涂有 羟基磷灰石（HA）与掺入抗生素，显示出显着降低细菌生长速度， 在模拟体液中长时间浸泡期间保持其机械性能。未包被对照品丢失 在浸泡测试期间，它们的机械强度大部分降低。第二阶段将通过以下方式扩大有希望的成果： 优化羟基磷灰石涂层，这是应用N2生物医学的专有工艺，以产生一个 在低温下形成薄的、耐用的层，从而保持HA源材料的性质和 温度敏感材料，如抗生素。我们会继续研制一种涂层， 不仅有助于启动骨生长，而且还调节镁基质的溶解速率， 释放抗生素，从而防止感染。体内研究将使用优化的HA涂层Mg植入物， 一种研究骨生长启动、植入物溶解和抗生素抗菌功效的大鼠模型， 被结合到涂层中。这项计划的成功可能会减少或消除目前的 需要后续手术从患者体内取出植入物或珠。总体成功，通过 第三阶段商业化可能会引发植入物行业的革命，并使临床 通过降低与翻修手术相关的成本和疼痛， 取出植入物

Project Summary Magnesium (Mg) and its alloys have attracted increasing interest for use as biodegradable implants, such as fixation devices for orthopedic and cranio-maxillofacial surgeries, due to their promising mechanical and biological properties, as well as their ability to degrade and resorb in the body. The overall aim of the Phase II program is to extend encouraging Phase I results in which biodegradable magnesium beads, coated with hydroxyapatite (HA) with an incorporated antibiotic, showed significant reduction of bacterial growth-rate and retained their mechanical properties during extended immersion in simulated body fluid. Uncoated controls lost much of their mechanical strength during the immersion tests. Phase II will extend the promising results by optimizing the hydroxyapatite coating, which is applied by N2 Biomedical's proprietary process to produce a thin, durable layer at low temperature, thereby retaining the properties of the HA source material and viability of temperature-sensitive material, such as an antibiotic. We will continue to develop a coating in which the HA will not only help initiate bone growth but also regulate the dissolution rate of the magnesium substrate and the release of the antibiotic, thus preventing infection. In vivo studies will use optimized HA-coated Mg implants in a rat model to study initiation of bone-growth, implant dissolution, and antibacterial efficacy of the antibiotic that is incorporated in the coating. Success of this program could lead to reduction or elimination of the present need for a subsequent operation to remove an implant or beads from the patient. Overall success through Phase III commercialization could start a revolution in the implant industry and a significant shift of the clinical paradigm in craniofacial and orthopedic surgery by reducing cost and pain associated with revision surgeries for implant removal.