Institute of Physiology, Medical Faculty, University of Ljubljana, Slovenia.
NMR Biomed. 2012 Sep;25(9):1056-62. doi: 10.1002/nbm.2770. Epub 2012 Jan 16.
The prognostic potential of apparent diffusion coefficient (ADC) mapping was studied as complemented by high-resolution 3D T(1)-weighted MRI in the assessment of dentin-pulp complex response to caries. Twenty-six extracted human teeth, with or without caries lesions of different grades in accord with the International Caries Detection and Assessment System (ICDAS), were analyzed by high-resolution MRI at 2.35 T. A signal rise in demineralized hard dental tissues in high-resolution T(1)-weighted MR images enabled assessment of the demineralization depth over the whole range of ICDAS scores. ADC maps of the teeth were calculated from corresponding diffusion-weighted images of four different b values: 0, 132, 317, 635 s/mm(2). These maps enabled reliable differentiation between intact (ADC > 1.0·10(-9) m(2)/s) and affected (ADC < 1.0·10(-9) m(2)/s) regions of dental pulp. Linear regression analyses of demineralization depth in relation to ICDAS score and then also to average ADC of dental pulp showed that a demineralization depth increase of one millimeter corresponds to an ICDAS score increase of 1.2 and an average ADC decrease of 0.07·10(-9) m(2)/s. Results of the study indicate that the average ADC value of dental pulp could be used as a potential marker to assess tissue response to caries comparable to that of ICDAS scoring.
研究了表观扩散系数 (ADC) 图在评估龋齿对牙本质牙髓复合体反应中的预测潜力，并补充了高分辨率 3D T1 加权 MRI。在 2.35 T 下，对 26 颗提取的人类牙齿进行了高分辨率 MRI 分析，这些牙齿有或没有不同等级的龋齿病变，符合国际龋齿检测和评估系统 (ICDAS)。高分辨率 T1 加权 MR 图像中脱矿硬质牙组织的信号升高使我们能够评估 ICDAS 评分范围内的整个脱矿深度。从四个不同 b 值（0、132、317、635 s/mm2）的相应扩散加权图像中计算了牙齿的 ADC 图。这些图谱能够可靠地区分完整（ADC > 1.0·10(-9) m2/s）和受影响（ADC < 1.0·10(-9) m2/s）的牙髓区域。脱矿深度与 ICDAS 评分的线性回归分析，以及随后与牙髓平均 ADC 的线性回归分析表明，脱矿深度增加 1 毫米对应 ICDAS 评分增加 1.2 和牙髓平均 ADC 降低 0.07·10(-9) m2/s。研究结果表明，牙髓的平均 ADC 值可作为评估组织对龋齿反应的潜在标志物，与 ICDAS 评分相当。
