Schmidlin P R, Tepper S A, Scriba H, Lutz F
Clinic for Preventive Dentistry, Periodontology and Cariology, Dental Institute, University of Zurich, Plattenstrasse 11, 8028 Zürich, Switzerland.
J Dent. 2002 Sep-Nov;30(7-8):305-11. doi: 10.1016/s0300-5712(02)00043-x.
To investigate the use of computer-assisted densitometric image analysis (CADIA) to detect incipient approximal carious lesions in vitro and to compare areas of demineralization and mechanically induced lesions by radiographic visual inspection.
Thirty-six extracted non-carious human molars were demineralized in a defined approximal area of interest (AOI) using a gel system (pH 4.8) applied over 15 weeks. Standardized digital radiographs were taken before and after creation of caries-like lesions and grayscale values were measured within the AOI. For another group of eight teeth, artificial defects were mechanically induced by a diamond bur and densitometric analysis was performed. Statistical significance was tested using the Wilcoxon test and set at p < or = 0.05. In addition, radiographs were interpreted by visual examination by six experienced dentists. The sensitivity and specificity for both study groups were determined in comparison to a baseline group of untreated teeth. Polarized light microscopy and SEM analysis were used to evaluate changes in the subsurface mineralization pattern and surface micromorphology.
Densitometric comparison of images from identical regions in control teeth revealed no significant grayscale value differences within the AOI, whereas a significant decrease (p < or = 0.05) was observed in the demineralized group. Mechanically induced lesions also showed a significant densitometric decrease (p < or = 0.05). The sensitivity of visual inspection of radiographs of demineralized areas was 0%. In contrast, the sensitivity for the detection of a mechanical defect of 0.1mm, which was the same subsurface extension as the histologically determined demineralization, increased to 52%. Specificity was 100% for all groups.
CADIA is able to detect very small changes in mineralization of incipient carious approximal lesions in vitro. The findings presented in this investigation may improve the subtraction method used for diagnosis and monitoring of approximal caries, as well as prophylactic measures.
研究计算机辅助密度测量图像分析（CADIA）在体外检测早期邻面龋损的应用，并通过X线视觉检查比较脱矿区域和机械诱导损伤区域。
36颗拔除的无龋人类磨牙在特定的邻面感兴趣区域（AOI）使用凝胶系统（pH 4.8）进行15周的脱矿处理。在创建类龋损前后拍摄标准化数字X线片，并在AOI内测量灰度值。对于另一组8颗牙齿，用金刚砂车针机械诱导人工缺损并进行密度测量分析。采用Wilcoxon检验进行统计学显著性检验，设定p≤0.05。此外，由6名经验丰富的牙医通过视觉检查解读X线片。与未处理牙齿的基线组相比，确定两个研究组的敏感性和特异性。使用偏光显微镜和扫描电镜分析评估表面下矿化模式和表面微观形态的变化。
对照牙齿相同区域图像的密度测量比较显示，AOI内灰度值无显著差异，而脱矿组观察到显著降低（p≤0.05）。机械诱导损伤也显示出显著的密度测量降低（p≤0.05）。脱矿区域X线片视觉检查的敏感性为0%。相比之下，检测0.1mm机械缺损（与组织学确定的脱矿具有相同的表面下延伸）的敏感性提高到52%。所有组的特异性均为100%。
CADIA能够在体外检测早期邻面龋损矿化的非常小的变化。本研究结果可能会改进用于邻面龋诊断和监测的减法方法以及预防措施。
