Department of Orthodontics, Riga Stradinš University, Riga, Latvia.
Department of Orthodontics, Riga Stradinš University, Riga, Latvia.
Am J Orthod Dentofacial Orthop. 2020 May;157(5):719-727. doi: 10.1016/j.ajodo.2019.12.012.
The objective of this research was to compare the predictive value of panoramic radiographs (PRs) and cone-beam computed tomography (CBCT) scans for the estimation of root resorption, spontaneous eruption of a canine, and time for orthodontic traction.
CBCT scans and PR images of 88 patients (27 male and 61 female; aged between 11 and 44 years) with 106 palatally displaced maxillary canines were retrieved from a database. Predictive values of several radiographic parameters, including the 3-dimensional angle of the canine, were analyzed using the area under the curve and multiple regression analysis.
The angle to the midline and canine position category had a discriminative ability for root resorption of the central incisors with area under the curve values of 0.63 (95% confidence interval, 0.56-0.79) and 0.83 (95% confidence interval, 0.75-0.91), respectively. PR measurements were not reliable predictors of resorptions, except severe resorptions, of the lateral incisors and the premolars. The measurements describing the position of the canine in relation to the midline could predict spontaneous eruption of the canine, regardless of the imaging method. The canine angle to the midline assessed on CBCT was significantly associated with traction time of the canine, producing the following equation: canine traction time = 49.6 - 0.24 × canine angle to the midline (r = 0.360).
Only severe resorptions of roots can be predicted with PRs. The use of CBCT is indicated in cases of impacted canines.
本研究的目的是比较全景片(PR)和锥形束 CT(CBCT)扫描对预测牙根吸收、恒尖牙自行萌出和正畸牵引时间的价值。
从数据库中检索了 88 名患者(27 名男性和 61 名女性;年龄在 11 至 44 岁之间)的 106 例上颌腭侧错位恒尖牙的 CBCT 扫描和 PR 图像。使用曲线下面积和多元回归分析分析了几个放射学参数的预测值,包括恒尖牙的三维角度。
角度到中线和尖牙位置类别对中切牙牙根吸收具有鉴别能力,曲线下面积值分别为 0.63(95%置信区间,0.56-0.79)和 0.83(95%置信区间,0.75-0.91)。PR 测量值除了对侧切牙和前磨牙的严重吸收外,不是牙根吸收的可靠预测指标。描述尖牙与中线相对位置的测量值可以预测尖牙的自行萌出,而与成像方法无关。CBCT 评估的尖牙与中线的角度与尖牙的牵引时间显著相关,产生以下方程:尖牙牵引时间=49.6-0.24×尖牙与中线的角度(r=0.360)。
PR 仅可预测严重的牙根吸收。在埋伏尖牙的情况下,应使用 CBCT。