Abstract: Objective    To study the effect of rapid molar intruder （RMI） on skeletal open bite. Methods    Seven skeletal open bite patients were orthodontically treated with RMI. The first molars were attached to transpalatal arch and mandibular lingual arch. No other intrude force was applied.  Results    All the patients felt uncomfortable in the first week and then adapted to that. The over-bites attained 1～2.3 mm after 3 to 7 months. Conclusion    The RMI appliance can correct skeletal open bite effectively.

Key words: rapid molar intruder, open bite, molar intrusion

摘要： 目的    评价应用快速磨牙压低器（RMI）压低过长磨牙以矫正骨性前牙开牙合畸形的临床效果。方法    选择2009年1月至2011年9月佛山市口腔医院正畸科收治的后牙区过度生长的骨性前牙开牙合患者7例，在磨牙上安装RMI压低磨牙，被压低磨牙上粘接腭杠和舌弓。不施加其它口内外辅助压低力。结果    戴RMI后1周内所有患者均存在不适感，1周后一般可适应。3～7个月后患者前牙覆牙合达到1.0～2.3 mm。结论    RMI可有效地矫正由后牙区过度生长所导致的骨性前牙开牙合畸形。

关键词: 快速磨牙压低器, 开牙合畸形, 磨牙压低