成人顏面不對稱治療計畫之判定:單純矯正治療或合併正顎手術

Treatment Decision in Adult Patients with Facial Asymmetry： Orthodontic Therapy or Orthognathic Surgery

歐凱捷(Kai-Chieh Ou)

指導教授 ： 張宏博

共同指導教授 ： 曾于娟(Yu-Chuan Tseng)

高雄醫學大學/口腔醫學院/牙醫學研究所/碩士(2010年)

摘要

研究目的：
顏面不對稱 ( facial asymmetry ) 是一項異常咬合患者常見的臨床特徵之ㄧ，掩飾性齒顎矯正治療能夠有效地矯治輕度甚至中度骨性顏面偏斜情形，至於嚴重的顏面不對稱可能需要正顎手術合併齒顎矯正治療才能予以改正。傳統測顱片雖為二維影像系統，但在診斷不對稱上仍是具有參考意義與價值的重要工具。本研究目的在於探討顏面不對稱成人病患採用單純矯正治療和矯正合併手術治療兩種不同治療計畫，在治療前齒顎顱顏結構的特徵與差異，進而幫助顏面不對稱患者臨床診斷與治療。

研究方法：
選取顏面不對稱患者，分單純矯正治療組 30 人，以及矯正合併手術治療組 30 人，共 60 人。分別描繪其治療前之正面測顱 X 光片，利用傳統測顱分析方法，共採用 11 個標記點及 51 個測量項目，利用電腦軟體 ( Winceph ) 測量，將測量項目結果進行雙樣本 t 檢定分析及 two-way ANOVA，更進一步利用 ROC 分析，找出判定兩種治療計畫的鑑別因子。

研究結果：
顏面不對稱矯正合併手術治療組，下顎骨左右不對稱性，不論在角度、與寬度比例上，差異性都比較大，也就是下臉部三分之ㄧ偏斜情形較為嚴重，上顎骨體左右寬度比例差異較大，左右牙弓寬度比例差異較大。經 ROC 分析，在判定手術或非手術治療之間，最具臨床意義的測量項目與數據，依序為：下顎骨與臉部中線偏移角度 ( mandible shift angle ) ≧ 4.1 度，Ramus 與下臉部中線夾角差 ( ∠Ra-Me-ANS ) ≧ 3.40 度，顴骨與下臉部中線夾角差 ( ∠Zy-Me-ANS ) ≧ 5.30 度，外側眼眶骨與下臉部中線夾角差 ( ∠GWSO-Me-ANS ) ≧ 4.90 度，上顎骨與下臉部中線夾角差 ( ∠J-Me-ANS ) ≧ 2.10 度，下顎骨角最外側寬度比例 ( Go(ver.)-M-ANS ratio ) ≧ 1.11，牙弓寬度比例 ( Mx6(ver.)-M-ANS ratio ) ≧ 1.12，下顎骨前角切跡寬度比例 ( Ag(ver.)-M-ANS ratio ) ≧ 1.11，下顎骨前角切跡與下臉部中線夾角差 ( ∠Ag-Me-ANS ) ≧ 4.90 度，下顎骨前角切跡到下頦點長度比例 ( Ag-Me ratio ) ≧ 1.11。

結論：
顏面不對稱患者，單純矯正治療組與矯正合併手術治療組，在齒顎顱顏上的確存在許多差異，這些顯著差異可提供臨床治療計畫擬定
的參考。若符合上述具臨床意義的十項條件，是屬於須尋求正顎手術治療的病患，其中前六項，便具有良好的臨床診斷價值，需以手術治療之可能性達七成。

關鍵字

顏面不對稱 ； 正顎手術 ； 矯正治療 ； 受試者工作特徵分析

並列摘要

Objective：
Facial asymmetry is a common feature in orthodontic patients. Mild skeletal facial asymmetry can be treated effectively by camouflaged orthodontic technique. Orthodontic treatment combined with orthognathic surgery would be suggested in some extreme cases. Although traditional posteroanterior cephalogram was 2D image, it was still full of reference meaning and value for diagnosing the asymmetric component in craniofacial area. The objectives of this research was to investigate the differences in morphological characteristics of facial asymmetry patient who can treated by orthodontic treatment only or orthognathic surgery. To find the most important morphological factors that influence the treatment planning and predict probability of orthognathic surgery.

Material and Method：
The pre-treatment lateral cephalograms of two groups of 60 subjects ( 30 orthodontic treatments and 30 surgical treatments) with facial asymmetry were analyzed. Eleven landmarks and fifty-one angular and proportional measurements were made. Two sample t test and receiver operating curve ( ROC ) analysis were applied to identify the dentoskeletal variables that best separate the two groups.

Result：
The findings of the study indicated that facial asymmetry patients with orthognathic surgery present with significantly mandibular asymmetric morphology in aspect of angles and linear proportions, larger linear dimensional proportion of the maxillae and arch width. The following terms and digits were extracted by ROC curves in sequence : Mandible shift angle ≧ 4.1°, included angle difference between ramus to lower facial midline ( ∠Ra-Me-ANS ) ≧ 3.40°, included angle difference between zygion to lower facial midline ( ∠Zy-Me-ANS ) ≧ 5.30°, included angle difference between latero-orbitale to lower facial midline ( ∠GWSO-Me-ANS ) ≧ 4.90°, included angle difference between jugal process to lower facial midline ( ∠J-Me-ANS ) ≧ 2.10°, right/left vertical line ratio between gonion and facial midline ( Go(ver.)-M-ANS ratio ) ≧ 1.11, right/left arch width ratio ( Mx6(ver.)-M-ANS ratio ) ≧ 1.12, right/left vertical line ratio between antegonion and facial midline ( Ag(ver.)-M-ANS ratio ) ≧ 1.11, included angle difference between antegonion to lower facial midline ( ∠Ag-Me-ANS ) ≧ 4.90°, right/left line ratio between antegonion and menton ( Ag-Me ratio ) ≧ 1.11.

Conclusion:
The ten measurements and cut-off points can be the guidelines in determining the treatment modalities for facial asymmetry patients. But the patient’s opinions and functional factors should also be considered.

並列關鍵字

facial asymmetry ； orthognathic surgery ； orthodontic therapy ； receiver operating characteristic ( ROC ) analysis

參考文獻

參考文獻

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