Section of Dentistry, Department of Surgery, The Aga Khan University Hospital, Karachi, Pakistan.
Section of Dentistry, Department of Surgery, The Aga Khan University Hospital, Karachi, Pakistan.
Am J Orthod Dentofacial Orthop. 2022 Jul;162(1):58-65. doi: 10.1016/j.ajodo.2021.02.023. Epub 2022 Feb 10.
Class II malocclusion is most commonly treated using maxillary premolar extractions. The objective of this study was to predict cephalometric parameters associated with favorable facial soft-tissue profiles in adult Asian subjects with Class II malocclusion treated via maxillary premolar extractions.
A cross-sectional study was performed with 46 patients equally divided into favorable (FG) and unfavorable groups. The sample was divided on the basis of subjective and objective criteria. Subjectively, pretreatment and posttreatment facial silhouettes were shown to the panel of orthodontists to rate via the visual analog scale. Objectively, posttreatment soft-tissue cephalometric variables were taken. The sample receiving 60% visual analog scale and ideal posttreatment soft-tissue measurements were included in FG. Paired t test and independent t test were applied to determine the significant changes within and between both groups. To predict the cephalometric and occlusal variables associated with FG outcome, the Cox regression analysis was applied.
On the evaluation of pretreatment cephalometric variables, the independent t test showed statistically significant differences for UI-NA (P = 0.42), Wits appraisal plane (0.010), upper lip to E-line (0.047), and interincisal angle (P = 0.049). Evaluation of the pretreatment occlusal variables the independent t test and chi-square test showed overjet (P = 0.018) and molar relationship (P = 0.045) to be statistically significant. The Cox regression analysis showed no cephalometric or occlusal variables to be statistically significant to predict the soft-tissue outcomes. A statistically significant strong correlation was also observed between the subjective and objective evaluation methods.
Cephalometric analysis may be more valuable as a diagnostic rather than a predictive tool for favorable soft-tissue outcomes.
II 类错颌畸形最常采用上颌第一前磨牙拔除进行治疗。本研究的目的是预测经上颌第一前磨牙拔除治疗的 II 类错颌成年亚洲患者中，与有利的面型软组织侧貌相关的头影测量参数。
采用回顾性研究，46 名患者平均分为两组，即有利组（FG）和不利组。样本根据主观和客观标准进行分组。主观上，向正畸医师小组展示治疗前后的面型轮廓，并通过视觉模拟量表进行评分。客观上，测量治疗后面部软组织的头影测量学变量。将视觉模拟量表评分达到 60%和理想的治疗后面部软组织测量结果的患者纳入 FG 组。采用配对 t 检验和独立 t 检验比较两组间和组内的显著变化。为了预测与 FG 结果相关的头影测量和咬合变量，应用 Cox 回归分析。
在评价治疗前面部软组织头影测量学变量时，独立 t 检验显示，UI-NA（P=0.42）、Wits 审美平面（0.010）、上唇至 E 线（0.047）和切牙间角（P=0.049）有统计学意义。在评价治疗前面部软组织咬合变量时，独立 t 检验和卡方检验显示，覆盖（P=0.018）和磨牙关系（P=0.045）有统计学意义。Cox 回归分析显示，头影测量和咬合变量均不能作为预测软组织结果的统计学显著因素。主观和客观评价方法之间也观察到了统计学上显著的强相关性。
头影测量分析可能更适合作为诊断工具，而不是预测有利软组织结果的工具。
