Ghazizadeh Maryam, Sheikhi Mahnaz, Aminian Maedeh, Ghazizadeh Mohammad Moein
Department of Oral and Maxillofacial Radiology, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran.
Dental Research Center, Department of Maxillofacial Radiology, Dental Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran.
Dent Res J (Isfahan). 2020 Aug 14;17(4):266-272. eCollection 2020 Jul-Aug.
Two-dimensional intraoral radiography is the most common tool for recognizing root fractures. Improving the quality of images by means of enhancement tools can increase the recognition power of them. The aim of this study is to evaluate the effect of digital image enhancement on vertical and horizontal root fractures (HRFs) diagnostic accuracy.
In this study, 100 human extracted teeth, involving 50 mandibular premolars and 50 maxillary incisors, were investigated. In total, 25 premolar teeth were vertically fractured and other 25 sound teeth served as testing group. According to the verified methods, 25 incisor teeth were fractured and other 25 teeth of this group served as testing ones. Following, by using the charge-coupled device sensor, preapical digital images were recorded. The original images were altered using reverse-contrast and colorization enhancement tools. Two different observers independently investigated all of the images. Receiver operating characteristic analysis was used to calculate the area under the curve (AUC) and sensitivity and specificity of all images. Data analyzde using receiver operating characteristic (ROC) analysis. Two-ways variance analysis was used to assess differences in the values ( = 0.05 ).
AUC and sensitivity and specificity related to the original, reverse-contrast, and colorized images were calculated (0.84, 0.64, 0.99), (0.84, 0.64, 0.96), and (0.82, 0.64, 0.92) respectively, for vertically root fractured images. AUC and sensitivity and specificity related to the original, reverse-contrast, and colorized images were calculated (0.49, 0.44, 0.56), (0.50, 0.44, 0.60), and (0.48, 0.48, 0.48), respectively, for horizontally root-fractured images.
The results of the present study revealed that reverse-contrast and colorized enhancement filters cannot be used as critical methods in detecting vertical and HRF.
二维口腔内放射摄影是识别牙根折断最常用的工具。通过增强工具提高图像质量可以增强对牙根折断的识别能力。本研究的目的是评估数字图像增强对垂直和水平牙根折断（HRF）诊断准确性的影响。
在本研究中，对100颗拔除的人类牙齿进行了研究，其中包括50颗下颌前磨牙和50颗上颌切牙。总共25颗前磨牙垂直折断，另外25颗完好牙齿作为测试组。按照验证方法，25颗切牙折断，该组另外25颗牙齿作为测试对象。随后，使用电荷耦合器件传感器记录根尖周数字图像。使用反转对比度和彩色增强工具对原始图像进行处理。两名不同的观察者独立观察所有图像。采用受试者操作特征分析来计算曲线下面积（AUC）以及所有图像的敏感性和特异性。使用受试者操作特征（ROC）分析进行数据分析。采用双向方差分析评估数值差异（α = 0.05）。
对于垂直牙根折断的图像，与原始图像、反转对比度图像和彩色图像相关的AUC、敏感性和特异性分别计算为（0.84, 0.64, 0.99）、（0.84, 0.64, 0.96）和（0.82, 0.64, 0.92）。对于水平牙根折断的图像，与原始图像、反转对比度图像和彩色图像相关的AUC、敏感性和特异性分别计算为（0.49, 0.44, 0.56）、（0.50, 0.44, 0.60）和（0.48, 0.48, 0.48）。
本研究结果表明，反转对比度和彩色增强滤镜不能作为检测垂直和水平牙根折断的关键方法。
