Department of Orthodontics, Faculty of Medicine, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Leuven, Belgium.
Am J Orthod Dentofacial Orthop. 2011 Sep;140(3):e129-39. doi: 10.1016/j.ajodo.2011.03.021.
The most frequent adverse effect of canine impaction is resorption of the adjacent incisors. The subjective image quality and the radiographic diagnostic accuracy for detection of simulated canine-induced external root resorption lesions in maxillary lateral incisors were compared among 6 cone-beam computed tomography (CBCT) systems in vitro.
A child cadaver skull in the early mixed dentition was obtained. This skull had an impacted maxillary left canine and allowed a reliable simulation. Simulated root resorption cavities were created in 8 extracted maxillary left lateral incisors by the sequential use of 0.16-mm diameter round burs in the distopalatal root surface. Cavities of varying depths were drilled in the middle or apical thirds of each tooth root according to 3 setups: slight (0.15, 0.20, and 0.30 mm), moderate (0.60 and 1.00 mm), and severe (1.50, 2.00, and 3.00 mm) resorption. The lateral incisors, including 2 intact teeth, were repositioned individually in the alveolus with approximal contacts to the impacted maxillary left canine. Six sets of radiographic images were obtained with 3D Accuitomo-XYZ Slice View Tomograph (J. Morita, Kyoto, Japan), Scanora 3D CBCT (Soredex, Tuusula, Finland), Galileos 3D Comfort (Sirona Dental Systems, Bensheim, Germany), Picasso Trio (E-WOO Technology, Giheung-gu, Republic of Korea), ProMax 3D (Planmeca OY, Helsinki, Finland), and Kodak 9000 3D (Trophy, Croissy-Beaubourg, France) for each tooth setup. The CBCT images were acquired and subsequently analyzed by 12 observers. Linear models for repeated measures were used to compare the CBCT systems for the image quality and the degree of agreement between the diagnosed severity of root resorption and the true severity.
The differences in the image quality between CBCT systems were statistically significant (P <0.001). The root resorption scores between CBCT systems showed a significantly higher score for the ProMax when compared with the Galileos and the Kodak. However, the differences in agreement between the diagnosed severity of root resorption and the true severity for all resorption sizes were not significantly different (P >0.05) among the different CBCT systems.
High image quality is important when detecting root resorption. The CBCT systems used in this study had high accuracy with no significant differences between them in the detection of the severity of root resorption.
犬齿阻生最常见的不良反应是邻接切牙的吸收。本研究旨在比较 6 种锥形束 CT（CBCT）系统体外检测上颌侧切牙犬齿诱导的外吸收根面病变的主观图像质量和放射诊断准确性。
从一名处于早期混合牙列的儿童尸体头颅中获取一个左侧上颌埋伏犬牙，并可靠地模拟了 8 颗离体上颌左侧侧切牙的根吸收腔。通过在远中腭根表面依次使用 0.16mm 直径的圆形车针，在每颗牙齿的根中或根尖三分之一处钻取不同深度的吸收腔，根据 3 种设置，制备出轻度（0.15、0.20 和 0.30mm）、中度（0.60 和 1.00mm）和重度（1.50、2.00 和 3.00mm）吸收的腔。将侧切牙，包括 2 颗完整的牙齿，分别重新定位在牙槽骨中，与左侧上颌埋伏犬牙邻接。对于每个牙齿设置，使用 3D Accuitomo-XYZ Slice View Tomograph（J.Morita，京都，日本）、Scanora 3D CBCT（Soredex，图苏拉，芬兰）、Galileos 3D Comfort（Sirona Dental Systems，本希姆，德国）、Picasso Trio（E-WOO Technology，Giheung-gu，大韩民国）、ProMax 3D（Planmeca OY，赫尔辛基，芬兰）和 Kodak 9000 3D（Trophy，Croissy-Beaubourg，法国）分别获得 6 组放射图像。使用线性重复测量模型比较 CBCT 系统的图像质量和诊断的根吸收严重程度与真实严重程度之间的一致性程度。
CBCT 系统之间的图像质量差异具有统计学意义（P<0.001）。CBCT 系统之间的根吸收评分显示，ProMax 系统的评分明显高于 Galileos 和 Kodak 系统。然而，对于所有吸收尺寸，诊断的根吸收严重程度与真实严重程度之间的一致性差异在不同的 CBCT 系统之间没有统计学意义（P>0.05）。
在检测根吸收时，高图像质量很重要。本研究中使用的 CBCT 系统具有较高的准确性，在检测根吸收严重程度方面没有显著差异。
