改良上颌斜面导板与Twin-block矫治器在前导下颌中的作用比较

Comparison of the effects resulted by modified maxillary oblique plate and Twin-block in advancing mandible

目的:评估改良斜面导板在前导下颌中的作用。方法:选择12例Ⅱ类Ⅱ分类伴下颌后缩患者,设为第1组,男4例,女8例,平均年龄11岁8个月。先采用上颌固定矫治器纠正上前牙内倾,再采用改良上颌斜面导板前导下颌;同时选择12例Ⅱ类Ⅰ分类伴下颌后缩患者,设为第2组,男5例,女7例,平均年龄11岁6个月,采用Twin-block前导下颌;对2组患者前导下颌的疗效通过治疗前后头颅侧位定位片进行评估、对比,采用SAS6.0软件包对数据进行统计学处理。结果:2组患者下颌均向前生长,第1组下前牙唇向倾斜较第2组明显,但差异无统计学意义(P>0.05);下颌第一磨牙近中向及向的移动,第2组显著大于第1组,差异有统计学意义(P<0.05)。结论:矫治Ⅱ类Ⅱ分类伴下颌后缩的患者,采用改良上颌斜面导板前导下颌不失为一种经济、简化、有效的方法。

PURPOSE： The aim of this study was to evaluate the effects resulted by modified maxillary oblique plate in advancing mandible. METHODS： Twelve Class Ⅱ division Ⅱ cases （4 males, 8 females） with mandibular retrusion were selected as group 1 aligned by fixed appliances in the upper arches, and their mandibles were advanced by the modified maxillary oblique plates. Meanwhile, twelve Class Ⅱ division Ⅰ cases （5 males, 7 females） with mandibular retrusion were selected as group 2 treated with the Twin-block. The average age was 11 years 8 months in group I, and 11 years 6 months in group 2. The effects of advancing mandible were compared between the two groups by analyzing cephalometric films before and after treatment with SAS6.0 software package. RESULTS： Mandibular advancement was achieved in the two groups. Mandibular anterior teeth labial tipping was more obvious in group 1 than in group 2, but without significant those （P〉0.05）. Both mesial and occlusal movements of the lower first molar in group 2 were more significant than those in group 1 （P〈0.05）. CONCLUSIONS： Based on the results, the modified maxillary oblique plate is an excellent appliance for the advancing mandible in Class Ⅱ division Ⅱ cases with the advantages of economics, simplification and effectiveness.