Abstract:

Objective    To evaluate the non-reduction treatment results and clinical treatment method for Angel' s Class Ⅱ deep overbite malocclusion cases by the application of microscrews anchorage and fixed bite flat. Methods    The study comprised 41 patients from Orthodontic Department of Liwan District Hospital of Guangzhou，from the year 2009 to 2012. All the patients presented with maxillary protrusion or little mandible intrusion treated with Smart-clip straight wire appliance by non-extraction of premolars. Self-drilling microscrews were impanted in the bilateral huccal alveolar bone between the maxillary first molars and second molar before bonding straight wire appliance.Upper canines were ligated backward to the microscrews in the initial treatment. When the main arch was stable enough，the frontal teeth were retracted together with the microscrews anchorage and retracted teeth. The average treatment time was 19 months，and follow-up lasted 1 year after the treatment. The cephalometric films before and after the treatment were measured and compared. Results    Angel' s ClassⅡ malocclusion in 41 patients were corrected effectively，except for 2 failure cases. Patients' facial profile had been improved greatly. After the treatment，SNA angle、U6-Y、U1-Y、overbite and overject decreased significantly in Class Ⅱ division 1 malocclusion，and in the Class Ⅱ division 2 malocclusion cases， U1-Y U1-X and overbite decreased significantly，overject increased significantly；both differences had statistical significance （P < 0.05）. Conclusion    Angel's Class Ⅱ malocclusion can he treated effectively by microscrew anchorage and fixed bite flat，with no loss of molar anchorage. To the  maxillary protrusion or little mandible cases，non-reduction treatments is an effective method.

Key words: orthodontic anchorage, microscrew, fixed bite flat, Angel's Ⅱmalocclusion, non-reduction treatments

摘要：

目的    应用固定式平面导板配合种植钉牵引，采用非减数方法矫治安氏Ⅱ类深覆牙合，探讨其临床要点。方法    2009—2012年在广州市荔湾区口腔医院就诊的安氏Ⅱ类错牙合伴有轻度上颌前突或下颌轻度后缩患者41例，其中安氏Ⅱ1错牙合患者21例，Ⅱ2错牙合患者20例。采用上颌选择性拔除第三恒磨牙，下颌不拔牙或拔除第三磨牙，矫正器采用Smart-clip系列自锁托槽直丝弓矫治器，选用A1自攻型不锈钢微种植钉，在颧牙槽嵴区第一磨牙和第二磨牙交界区植入；制作固定式平面导板打开咬合，排齐整平后利用种植钉整体内收前牙，竖直磨牙或推磨牙向后，调整覆牙合覆盖及尖、磨牙关系至正常。结果    41例患者除2例种植体松动脱落，其余患者第一磨牙在前后向和垂直向均未发生显著性移动，患者颜面侧貌得到了明显改善，取得了较为满意的治疗效果。与矫治前相比，矫治后安氏Ⅱ1患者SNA角、U6-Y距、覆牙合及覆盖明显减小，差异均有统计学意义（P＜0.05）；安氏Ⅱ2患者U1-Y距、U1-X距及覆牙合明显减少，覆盖明显增加，差异均有统计学意义（P＜0.05）。结论    平面导板配合种植钉能够有效治疗安氏Ⅱ1和Ⅱ2错牙合患者，并达到竖直磨牙或推磨牙向后效果；对安氏Ⅱ类错牙合伴有轻度上颌前突或下颌轻度后缩患者，可选择非减数矫治。

关键词: 正畸支抗, 种植钉, 固定式平面导板, 安氏Ⅱ类错牙合, 非减数矫治