齒顎矯正對上呼吸道的影響系列之四：上顎撐寬對上呼吸道空間的影響

Literature Review: The Effect of Maxillary Expansion on Upper Airway

上顎快速擴張術（Rapid maxillary expansion）是矯正醫師藉由錨定於牙齒的擴張裝置，用機械的力量將上顎正中骨縫（median palatal suture）拉張，來達成增加上顎骨橫寬和牙弓周徑（arch perimeter）的目的。其骨矯正的效果（Orthopedic effect）除了使上顎正中骨縫拉張開來，改變上顎骨及牙弓的型態，並會使上顎齒槽骨架（maxillary alveolar shelves）旋轉，影響周圍的顱顏骨縫及鼻腔的幾何型態與功能。本篇回顧探討上顎快速擴張術對於上呼吸道的解剖構造和呼吸阻力的變化，以及對有鼻呼吸道阻塞和睡眠呼吸中止症的病人有何影響。文獻顯示，在具有生長潛力的病人身上，的確可觀察到鼻腔橫斷面面積和容積增加，使呼吸氣流阻力下降，改善呼吸模式；然而，這些統計量的變化是否具有臨床上的實質意義？或是只是統計上的顯著？能否確實改善孩童時期鼻咽空間過度狹窄造成的口呼吸，打鼾，及睡眠呼吸終止症候群依然有其爭議。

Rapid maxillary expansion (RME) is a common method used by orthodontists to increase the transverse dimension of maxillary arch and arch perimeter, by a tooth-borne device to stretch the median palatal suture through the mechanical force. The orthopedic effects produced by the RME device include not only opening the median palatal suture, but also rotating the maxillary alveolar shelves, which has an influence on the adjacent sutures of facial skeleton and the morphology of nasal cavities. This article reviewed the impact of RME on the anatomy of upper airway, respiratory flow resistance, and clinical relation with the nasal airway obstruction and obstructive sleep apnea. The reviews showed an increase in maximum cross-sectional area and volume of the nasal cavity, and a decrease of respiratory flow resistance after RME therapy. However, the respiratory status is improved in the way of statistical significance, and the clinical significance is still in debate.