Ex vivo and in vitro synchrotron-based micro-imaging of biocompatible materials applied in dental surgery
Ex vivo and in vitro synchrotron-based micro-imaging of biocompatible materials applied in dental surgery
复制标题
牙科手术中应用的生物相容性材料的基于同步加速器的离体和体外显微成像
DOI：
10.1117/12.858435
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
Goebbels J
中科院分区：
文献类型：
--
作者：
Rack A;Stiller M;Nelson K;Knabe C;Rack T;Zabler S;Dalügge O;Riesemeier H;Cecilia A;Goebbels J
多孔生物活性磷酸钙陶瓷或钛等生物相容性材料经常应用于牙科手术：陶瓷用于支持给定缺陷的局部骨再生，然后钛植入物代替失去的牙齿。目前种植牙科骨重建的金标准是自体骨移植物的使用。但是，引导骨再生（GBR）的概念已经成为一种可预测的、有充分记录的手术方法，使用生物材料（生物活性磷酸钙陶瓷）作为骨替代品也适用于这种应用。我们应用高分辨率同步加速器微断层扫描和随后的三维图像分析，以三维方式研究骨形成和骨替代材料的降解，将知识扩展到经典组织学的限制之外。在骨再生之后，钛基种植体对机械精度要求很高，特别是在采用两件式概念以保证密闭性的情况下。在这里，基于同步加速器的射线照相与传统的实验室射线照相相比，即使在这些高度衰减的物体中利用微尺寸特征时，也能产生高空间分辨率和高对比度。因此，我们可以用不同力学载荷下的标本研究两片式种植体界面微间隙的形成。我们可以证明具有锥形连接的种植体存在微间隙，并研究锥形种植体在加载过程中配合区的微观力学行为。微间隙是失败的潜在问题，即细菌渗漏，可诱导炎症过程。
Biocompatible materials such as porous bioactive calcium phosphate ceramics or titanium are regularly applied in dental surgery: ceramics are used to support the local bone regeneration in a given defect, afterwards titanium implants replace lost teeth. The current gold standard for bone reconstruction in implant dentistry is the use of autogenous bone grafts. But the concept of guided bone regeneration (GBR) has become a predictable and well documented surgical approach using biomaterials (bioactive calcium phosphate ceramics) which qualify as bone substitutes for this kind of application as well. We applied high resolution synchrotron microtomography and subsequent 3d image analysis in order to investigate bone formation and degradation of the bone substitute material in a three-dimensional manner, extending the knowledge beyond the limits of classical histology. Following the bone regeneration, titanium-based implants to replace lost teeth call for high mechanical precision, especially when two-piece concepts are used in order to guaranty leak tightness. Here, synchrotron-based radiography in comparison with classical laboratory radiography yields high spatial resolution in combination with high contrast even when exploiting micro-sized features in these kind of highly attenuating objects. Therefore, we could study micro-gap formation at interfaces in two-piece dental implants with the specimen under different mechanical load. We could prove the existence of micro-gaps for implants with conical connections as well as to study the micromechanical behavior of the mating zone of conical implants during loading. The micro-gap is a potential issue of failure, i. e. bacterial leakage which can induce an inflammatory process.