Antimicrobial Biodegradable Bone Graft for Craniofacial/Maxillofacial Application

项目摘要 镁及其合金作为可生物降解的植入物引起了越来越多的兴趣，例如 矫形外科和颅颌面外科的固定装置，由于其良好的机械和 生物特性，以及它们在体内降解和吸收的能力。第二阶段的总体目标 计划是扩大令人鼓舞的第一阶段结果，在这些结果中，生物可降解镁珠，涂层 羟基磷灰石(HA)与抗生素结合后，细菌生长速度显著降低， 在长时间浸泡在模拟体液中时，保持了它们的机械性能。未涂覆的控件丢失 在浸泡测试中，它们的机械强度很大。第二阶段将把有希望的成果扩大到 优化羟基磷灰石涂层，应用于氮气生物医学的专利工艺，以生产 薄层，在低温下耐用，从而保留了HA来源材料的特性和 对温度敏感的材料，如抗生素。我们将继续开发一种涂层，在这种涂层中，医管局将 不仅有助于启动骨骼的生长，而且还可以调节镁基质的溶解速度和 释放抗生素，从而防止感染。体内研究将使用优化的HA涂层镁植入物 一种研究骨生长启动、种植体溶解和抗生素抗菌效果的大鼠模型 被结合在涂层中。这一计划的成功可能导致现在的减少或消除 需要进行后续手术才能从患者体内取出植入物或珠子。通过以下途径获得全面成功 第三阶段的商业化可能会引发植入物行业的一场革命，并使临床 通过减少与翻修手术相关的成本和痛苦，在颅面和矫形外科手术中的范例 用于取出植入物。

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.