年輕成人安氏I類錯牙合亞型的X線頭影測量分析

[摘要]目的：分析年輕成人安氏Ⅰ類錯牙合亞型特征。方法：選取101例安氏Ⅰ類錯牙合年輕成年患者，拍攝顱頜定位X線片。用頭影測量“優選法”的17項測量指標，按水平方向和垂直方向進行聚類分析，并與正常人群進行比較。結果：測量指標按水平方向可聚類為3個亞類，即水平Ⅰ類、Ⅱ類和Ⅲ類，所占比例分別為17.8%、12.9%和65.3%。水平Ⅰ類特征：上頜略偏縮、下頜后縮，Ⅱ類錯牙合趨勢，上下中切牙唇傾；水平Ⅱ類特征：上頜前凸、下頜后縮，上下中切牙舌傾，上下唇相對于上下切牙突度大；水平Ⅲ類特征：上頜前凸、下頜后縮，上下中切牙唇傾，上下唇相對于上下切牙突度大。按垂直方向聚為Ⅰ類，特征是垂直方向發育不足，尤其是面下1/3為著，下頜呈后旋趨勢，上下唇突。結論：年輕成人安氏I類錯牙合水平方向分為3個亞類、垂直方向為Ⅰ類。總體趨勢是下頜后縮、面下1/3發育不足，但上頜骨、上下前牙和唇位等方面仍有一定的差異，臨床應針對性診治。

[關鍵詞]安氏I類錯牙合；牙頜面特征；頭影測量優選法；亞型

[中圖分類號]R783.5 [文獻標識碼]A [文章編號]1008-6455（2012）03-0462-03

Cephalometric analysis of the subdivision characteristic of Angle's ClassⅠmalocclusion in the young adults

CAI Liu-yi1，LIU lin-bo1，DING Yin2

(1.Department of Plastic Surgery，The First Affiliated Hospital，Zhengzhou University，Zhengzhou 450052，Henan，China;2.Department of Orthodontics，Stomatological Hospital，the Fourth Military Medical University)

Abstract: Objective To analyse the subdivision characteristic of Angle's ClassⅠmalocclusion in the young adults. Methods 101 samples with Angle's ClassⅠmalocclusion were selected from university students. X ray cephalometric films were photographed and analysed by \"well-selected method\" from the measurement software of stomatological hospital，the Fourth Military Medical University.And the seventeen quotas measurement results were accumulated into subdivisions at horizontal and vertical directions and compared with that of the normal occlusion. Results They were accumulated into 3 subdivisions at horizontal direction and 1 subdivision at vertical direction. The percentage of horizontal Ⅰ，Ⅱ and Ⅲ was 17.8%，12.9% and 65.3% accordingly.Compared with the normal occlusion people，horizontalⅠsubdivision showed slightly maxilla retrusion，mandible retrusion，Class Ⅱ malocclusion tendency and more labial inclined upper and lower central incisors.HorizontalⅡsubdivision showed maxilla protrusion，mandible retrusion，more lingual inclined upper and lower central incisors and more protruded lips.Horizontal Ⅲ subdivision showed maxilla protrusion、mandible retrusion、more labial inclined upper and lower central incisors and more protruded lips.VerticalⅠsubdivision indicated ill-developed facial lower third，a little more backward rotation and more protruded lips. Conclusion Horizontal 3 subdivisions and vertical 1 subdivision were included in the young adults with Angle's ClassⅠmalocclusion.The total tendency was mandible retrusion and ill-developed facial lower third，but different maxilla，central incisors and lip protrusion.

Key words:Angle's ClassⅠmalocclusion;dental and craniofacial characteristic;cephalometric roentgenography;subdivisions

安氏Ⅰ類錯牙合是正畸臨床最常見的錯牙合畸形，其矢狀方向和垂直方向特征比較明顯。本研究應用聚類分析的方法對安氏I類進行亞類的研究，分析其特征差異，為臨床診治提供依據和參考。

1 材料和方法

1.1樣本選擇：101里安氏Ⅰ類錯牙合樣本選自西安市11所大學2 098例新生，其中男53例，女48例，平均年齡分別為19.2歲和19.1歲。具體納入標準：①漢族，年齡18～23歲；②西安地區籍貫；③身體健康，發育良好，無正畸治療史，無面部外傷史；……