Gao Xue-Mei, Otsuka Ryo, Ono Takashi, Honda Ei-ichi, Sasaki Takehito, Kuroda Takayuki
Department of Orthodontic, Stomatology School, Peking University, Beijing 100081, China.
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi. 2005 Feb;40(2):137-40.
To examine adaptive changes in the shape of the upper airway during titrated mandibular advancement. Furthermore, to understand the mechanism of mandible-adjustable therapy to improve the ventilation.
Fourteen non-apnea participated in the study. A custom-made oral device was used to keep the mandible in titrated advancement at 0% (F0), 50% (F50), 75% (F75), 100% (F100) of the maximum advancement. Magnetic resonance imaging was used to investigate the difference in the shape of upper-airway in these 4 positions. Changes in the anteroposterior direction (AP), lateral direction (Lat) and its ratio (AP/Lat) were calculated, which were transformed into the percentage of the original ones.
The dose-dependent decrease of AP/Lat was found when the mandible was advanced (P = 0.0001). Lateral change rate in percentage increased by degrees (P = 0.0023), while the increase of anteroposterior change rate in percentage showed no statistical significance.
The shape of upper airway tended to be less round. The enlargement of upper airway during titrated mandibular advancement was mainly the result of enlargement in lateral direction.
研究下颌渐进性前移过程中上气道形态的适应性变化。此外，了解下颌可调节治疗改善通气的机制。
14名非呼吸暂停患者参与本研究。使用定制的口腔矫治器将下颌保持在最大前移量的0%（F0）、50%（F50）、75%（F75）、100%（F100）进行渐进性前移。采用磁共振成像研究这4种位置时上气道形态的差异。计算前后径（AP）、左右径（Lat）及其比值（AP/Lat）的变化，并换算为相对于初始值的百分比。
下颌前移时，AP/Lat呈剂量依赖性降低（P = 0.0001）。左右径变化率的百分比呈逐度增加（P = 0.0023），而前后径变化率的百分比增加无统计学意义。
上气道形态趋于变扁。下颌渐进性前移过程中上气道的扩大主要是左右径扩大的结果。
