Sui Tan, Sandholzer Michael A, Lunt Alexander J G, Baimpas Nikolaos, Smith Andrew, Landini Gabriel, Korsunsky Alexander M
Department of Engineering Science, University of Oxford, , Parks Road, Oxford OX1 3PJ, UK.
J R Soc Interface. 2014 Apr 9;11(95):20130928. doi: 10.1098/rsif.2013.0928. Print 2014 Jun 6.
Human dental tissues consist of inorganic constituents (mainly crystallites of hydroxyapatite, HAp) and organic matrix. In addition, synthetic HAp powders are frequently used in medical and chemical applications. Insights into the ultrastructural alterations of skeletal hard tissues exposed to thermal treatment are crucial for the estimation of temperature of exposure in forensic and archaeological studies. However, at present, only limited data exist on the heat-induced structural alterations of human dental tissues. In this paper, advanced non-destructive small- and wide angle X-ray scattering (SAXS/WAXS) synchrotron techniques were used to investigate the in situ ultrastructural alterations in thermally treated human dental tissues and synthetic HAp powders. The crystallographic properties were probed by WAXS, whereas HAp grain size distribution changes were evaluated by SAXS. The results demonstrate the important role of the organic matrix that binds together the HAp crystallites in responding to heat exposure. This is highlighted by the difference in the thermal behaviour between human dental tissues and synthetic HAp powders. The X-ray analysis results are supported by thermogravimetric analysis. The results concerning the HAp crystalline architecture in natural and synthetic HAp powders provide a reliable basis for deducing the heating history for dental tissues in the forensic and archaeological context, and the foundation for further development and optimization of biomimetic material design.
人类牙齿组织由无机成分（主要是羟基磷灰石微晶，HAp）和有机基质组成。此外，合成HAp粉末常用于医学和化学应用中。了解骨骼硬组织经热处理后的超微结构变化对于法医和考古研究中暴露温度的估计至关重要。然而，目前关于人类牙齿组织热诱导结构变化的数据有限。在本文中，采用先进的非破坏性小角和广角X射线散射（SAXS/WAXS）同步辐射技术来研究热处理后的人类牙齿组织和合成HAp粉末的原位超微结构变化。通过WAXS探测晶体学性质，而通过SAXS评估HAp晶粒尺寸分布变化。结果表明，在响应热暴露时，将HAp微晶结合在一起的有机基质起着重要作用。这通过人类牙齿组织和合成HAp粉末热行为的差异得到了突出体现。X射线分析结果得到了热重分析的支持。关于天然和合成HAp粉末中HAp晶体结构的结果为推断法医和考古背景下牙齿组织的加热历史提供了可靠依据，并为仿生材料设计的进一步发展和优化奠定了基础。
