应用微钛钉矫治上颌前突或双牙弓前突

目的研究应用微螺钉型种植体支抗治疗上前牙前突或双牙弓前突。方法15例正畸患者的上牙列前牙区牙齿覆盖在Ⅱ°以上，平均覆盖为9．9mm。内收前牙阶段应用自攻型微钛钉支抗种植体，植入上颌第一恒磨牙和上颌第二恒磨牙，或上颌第一恒磨牙和第二前磨牙颊侧根尖之间的牙槽间隔，以每侧100～150g力滑动内收前牙。比较内收前后头颅X线侧位片，测量前牙内收情况和磨牙支抗的变化。结果15例牙弓突度均得到明显改善，切牙切缘平均内收6．9mm，支抗磨牙平均前移0．4mm，磨牙在前后向和垂直向均未发生显著性移动，种植体保持了稳定。结论微钛钉支抗能够有效治疗上颌前牙前突或双牙弓前突患者，起到磨牙强支抗的效能。

Clinical study on treating maxillary protrusion or bimaxillary protrusion with microcrew anchorage

Objective To evaluate the treatment results of maxillary protrusion or bimaxillary protrusion eases by the application of mierocrew anchorage. Methods The study comprised 15 patients, whose ages ranged from 14.5 to 40.5 years, average （26.3 ± 6.2）years. All the patients presented maxillary protrusion, a mean of 9.9 mm in maxillary anterior teeth. Self- drilling microserews were implanted in the bilateral buccal alveolar bone between maxillary the first and the second molars or between the first molar and second premolar before bonding straight wire appliance. When the main arch was stable enough, the canine and lateral incisor were retracted respectively with the microscrew anchorage. 100g force each side was applied to miniscrew and retraced teeth. The cephalometric films before and after the relieving of upper anerior teeth croweing were measured and compared. Result Maxillary protrusion in 15 patients were corrected effectively. Incisors were retracted siginificantly . Molars were moved slightly forward. Central incisor and first molar had no significant changes in anteroposterior and vertical directions. Conclusion Maxillary wotrusion could be relieved effectively by microsrew anchorage, with no loss of molar anchorage.