Tovar-Calderón Marcela-María, Barrera-Mora José-María, Espinar-Escalona Eduardo, Puigdollers-Pérez Andreu, Herrera-Martínez Manuela, Llamas-Carreras José-María
PhD in Health Science. University of Seville.
Associate Professor of Orthodontics. University of Seville.
J Clin Exp Dent. 2021 Aug 1;13(8):e817-e825. doi: 10.4317/jced.58383. eCollection 2021 Aug.
To estimate whether there is skeletal and/or dental asymmetry in class II subdivision patients, between the Class II side and the Class I side using of cone beam computed tomography (CBCT).
A sample of 30 patients, from a private clinic, retrospectively selected; with a class II subdivision diagnosis requiring treatment, who underwent wide-field CBCT that met the inclusion criteria. The data was processed with Dolphin 3D version 11.95 Premium software. The craniometric points, as well as the spatial orientation scheme of the three-dimensional model were proposed by Craig Minich, (1).
The Class II subdivision side and the Class I side of each patient were compared through intramaxillary, intramandibular, and intermaxillary measurements, evaluating each one in three dimensions (sagittal, frontal, and axial). Also, the measurements made from the three-dimensional volume, were contrasted with those generated in the biplane views. The level of significance used was 0.05. Statistical analysis was performed using the R program (R Development Core Team), version 3.4.4. The intraoperative variability was previously verified using the Dahlberg formula. This error is 0.35 -1.10, so the spatial orientation and placement of craniometric points are repeatable and reliable.
Statistically significant differences have been found with respect to skeletal values and dentoalveolar position. Regarding the skeletal findings, the class II subdivision side is narrower and there is a shortening of the condylar branch. In the dentoalveolar position on this side, the upper molar and canine are in an advanced position, the lower molar is posterior and lower than the contralateral and the lower canine is in a delayed position. Furthermore, measurements made from a two-dimensional image cannot be extrapolated with those made directly from a three-dimensional volume. The problem is generated by a deviation in dental position as well as an underlying asymmetry. Class II subdivision, cone beam computed tomography, skeletal asymmetry, dentoalveolar position.
使用锥形束计算机断层扫描（CBCT）评估II类亚类患者II类侧与I类侧之间是否存在骨骼和/或牙齿不对称。
回顾性选取30例来自私人诊所的患者样本；诊断为需要治疗的II类亚类，且接受了符合纳入标准的广角CBCT检查。数据使用Dolphin 3D 11.95高级版软件进行处理。颅骨测量点以及三维模型的空间定向方案由克雷格·米尼奇提出，（1）。
通过上颌内、下颌内和颌间测量对每位患者的II类亚类侧和I类侧进行比较，在三个维度（矢状面、额面和轴面）上对每个部位进行评估。此外，从三维体积进行的测量与在双平面视图中生成的测量结果进行对比。使用的显著性水平为0.05。使用R程序（R开发核心团队）3.4.4版进行统计分析。术中变异性先前已使用达尔伯格公式进行验证。该误差为0.35 - 1.10，因此颅骨测量点的空间定向和定位是可重复且可靠的。
在骨骼值和牙槽位置方面发现了具有统计学意义的差异。关于骨骼检查结果，II类亚类侧更窄，髁突支有缩短。在该侧的牙槽位置，上颌磨牙和尖牙处于靠前位置，下颌磨牙靠后且低于对侧，下颌尖牙位置滞后。此外，从二维图像进行的测量不能直接外推到从三维体积进行的测量。该问题是由牙齿位置偏差以及潜在的不对称性引起的。II类亚类、锥形束计算机断层扫描、骨骼不对称、牙槽位置。
