Gröndahl K, Kullendorff B, Strid K G, Gröndahl H G, Henrikson C O
Department of Oral Radiology, School of Dentistry, University of Göteborg, Sweden.
J Clin Periodontol. 1988 Mar;15(3):156-62. doi: 10.1111/j.1600-051x.1988.tb01562.x.
Subtraction of serially obtained standardized radiographs of the marginal periodontal bone offers possibilities for an increased detectability of small bony changes compared to conventional radiography. In this study, the depth of artificially induced bone lesions in the alveolar crest was assessed by means of 125I absorptiometry. The results served as reference values when a series of radiographs containing lesions of various depths was interpreted by 10 examiners. Both conventional radiographs and subtraction images made from the conventional radiographs after digitization were interpreted. The ROC-curve technique was used to evaluate the two techniques. A close to perfect accuracy was found at a lesion depth corresponding to 0.49 mm of compact bone using the subtraction technique. A similar degree of accuracy was not reached for the conventional technique until the lesions were approximately 3 times deeper.
与传统放射照相术相比，连续获取边缘牙周骨的标准化X线片进行减法运算，有可能提高对微小骨变化的检测能力。在本研究中，通过¹²⁵I吸收测定法评估牙槽嵴人工诱导骨病变的深度。当10名检查者解读一系列包含不同深度病变的X线片时，这些结果用作参考值。对传统X线片以及数字化后的传统X线片制作的减法图像均进行了解读。采用ROC曲线技术评估这两种技术。使用减法技术时，在对应于0.49 mm密质骨的病变深度处发现了近乎完美的准确性。直到病变深度约为原来的3倍时，传统技术才达到类似的准确度。
