Samples of enamel and dentin from human molar teeth were heated in air from room temperature (25°C) up to 1200°C and the phase transition from hydroxyapatite (HAP) to tricalcium phosphate (β‐TCP) was recorded. The changes produced in morphology and chemical composition in the tooth during heating were analysed by light microscopy, scanning electron microscopy (SEM), characteristic x‐ray energy dispersion spectroscopy (EDS), x‐ray diffraction (XRD), electron diffraction, transmission electron microscopy (TEM) and high‐resolution electron microscopy (HRTEM). The results indicated a high correlation relationship among Ca content, P content, O content and Na content, and the existence of the Kirkendall effect during the HAP‐ β‐TCP phase transition.

中文翻译：

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在人类牙齿中观察到的从羟基磷灰石到 β-TCP 的热相变的电子显微镜分析

人类磨牙的牙釉质和牙本质样品在空气中从室温 (25°C) 加热到 1200°C，并记录了从羟基磷灰石 (HAP) 到磷酸三钙 (β-TCP) 的相变。通过光学显微镜、扫描电子显微镜 (SEM)、特征 X 射线能量色散谱 (EDS)、X 射线衍射 (XRD)、电子衍射、透射电子显微镜分析加热过程中牙齿形态和化学成分的变化。显微镜 (TEM) 和高分辨率电子显微镜 (HRTEM)。结果表明，Ca含量、P含量、O含量和Na含量与HAP-β-TCP相变过程中存在柯肯德尔效应之间存在高度相关性。