分析下顎牙弓後退之空間限制

Analysis of the Space Limitation for Mandibular Arch Distalization Using Cone Beam Computed Tomography

陳佳伶(Angelia Chen)

指導教授 ： 曾于娟

高雄醫學大學/口腔醫學院/牙醫學系碩士班/碩士(2017年)

摘要

研究目的： 本研究欲探討下顎後牙往後退之空間限制，分別從頰舌徑寬度及近遠心距離來評估下顎後牙後退之限制。
材料與方法： 本研究從67位未做過矯正之台灣人以錐狀射束電腦斷層量測下顎第二大臼齒牙根寬度及下顎後牙後區之骨脊寬度；另外近遠心部分使用下顎第二大臼齒牙根往後之最短距離。比較不同性別、左右邊、不同牙根接觸情形、智齒有無、異常咬合之骨脊寬度、遠心向後退的量。
結果： 下顎第二大臼齒後區齒槽骨寬督在男女、左右邊、異常咬合之骨脊寬度無顯著差異(p<0.05)；第二大臼齒牙根與皮質骨有接觸情形的骨脊寬度偏小，差異落在遠心向及根尖向的骨脊。有無智齒會影響下顎牙根後退量，但影響區主要在齒脊骨高度處。
結論： 研究結果顯示有49.2% (33/67)的下顎第二大臼齒牙根會與下顎皮質骨有接觸。比較頰舌徑骨脊寬度及近遠心向後退量，頰舌徑骨脊寬度為下顎牙弓後退之限制。

關鍵字

錐狀射束電腦斷層 ； 下顎牙弓整體後退 ； 骨脊寬度

並列摘要

Purpose: The purpose of this study is to invastigate the limitation of cortex contact with mandibular second molars, while mandibular second molars distalized.
Materials and Methods: Total database was 67 Taiwanese with 34 males and 33 females, evaluated with cone beam computed tomography. The space was evaluated in buccolingual and mesiodistal dimension. Different genders, bilateral sides, root contact condition, wisdom teeth, and malocclusion were taken into consideration.
Results: The mean age in the database was 23.9±2.72 year. There were no significant differences in the width of alveolar width between genders, bilateral sides, wisdom teeth, or malocclusion. The ridge width and alveolar width are smaller in contact group than in non-contact group (p<0.05). There is larger distalization distance in wisdom-teeth group.
Conclusion: The possibility of cortex contact was 49.2% before any orthodontic movement. The ridge width is smaller in the distal and apical direction. Comparing with ridge width and distalization distance, ridge width is the limitation for mandibular teeth distalization.

並列關鍵字

cone-beam computed tomography ； second molar distalization ； ridge width

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