雙軸式快速上顎擴張之牙齒移動效益

The Effects of Two-Hinged Rapid Palatal Expansion on Dental Structures

蔡文卿(Wen-Ching Tsai) ； 林紀廷(Chi-Ting Lin) ； 劉人文(Eric Jein-Wein Liou)

《中華民國齒顎矯正學雜誌》 17卷1期 (2005/03) Pp. 15-23

https://doi.org/10.30036/TJO.200503.0002

摘要

本研究的目的在於評估雙軸式快速上顎擴張器用於臨床治療的效果。20位唇顎裂患者，14位男性，6位女性，平均年齡12歲，均有上顎前側牙弓塌陷（V形牙弓），前牙錯咬的臨床特徵，治療目標在於將上顎前側牙弓擴張，上顎往前移動，改善牙齒咬合及顏面外觀。每位接受治療的患者，於上顎擴張前(T1)及擴張後(T2)，均取得上顎石膏模型，將模型影像輸入電腦加以平面化，應用電腦軟體詳加分析測量，以評估擴張前後牙齒位置之改變。結果顯示，橫向測量上，intercanine width增加量明顯比intermolar width增加量多，整體而言，同名牙齒間距離之增加量，是由上顎牙弓後方往前遞增，符合治療上的需求量。前後向測量上，牙齒均往前方移動，前牙區前移量最多，後牙區則移動較少，整體而言，牙齒前移量由後牙區往前牙區遞增，可改善水平覆咬的差距，亦符合治療上的需求。

關鍵字

快速上顎擴張 ； 雙軸式快速上顎擴張 ； 電腦計量 ； 橫向測量 ； 前後向測量

並列摘要

Anew type of two-hinged rapid palatal expander was developed to treat those cleft palate patients with Class Ill malocclusion and severely crowded maxillary dentition. The clinical characteristics of these patients were all present with collapsed and narrow V-shape arch form in the anterior segment of their maxillary dentition. The treatment aim was to expand the maxillary arch, protract the maxilla, and normalize occlusion as well as improve patient& facial profile.
The treatment effect of two-hinged rapid palatal expansion was assessed on 20 cleft palate adolescent patients (14 males, 6 females) with mean age of 12 years old. Pre-treatment (T1) and post-expansion (T2) study models of maxillary arch were collected, and the total sample were 40. The defined landmarks of the models were identified and digitized. The X and Y coordinates of the landmarks were loaded in the computer. Computerized calculation was performed according to the positional changes of the X and Y coordinates of the identical landmark before and after the expansion treatment.
The results indicated that, in terms of transverse parameter, inter-canine width increased more than that of inter-molar width. Generally, the changes of transverse arch width after expansion were progressively greater from molars to canine regions. This specific feature of expansion can actually normalize the narrow V-shape arch form. In terms of postero-anterior changes of maxillary dentition, all teeth were directed forwards by expansion. The anterior segment tended to moved forwards more than that of posterior segment. The progressive increment of forward movement of dentition from posterior to anterior teeth could also be revealed. This unique movement effectively enables clinicians to improve the overjet in the Class Ill cleft palate patients.

並列關鍵字

Rapid palatal expansion ； Two-hinged rapid palatal expansion ； Computerized calculation ； Transverse dimension change ； Anteroposterior dimension change