上颌前方牵引前反复扩缩效果及上前牙稳定性的比较

Comparison of the effect of expansion and contraction before maxillary traction and the stability of upper anterior teeth

目的对比上颌骨前方牵引前使用反复扩缩与直接前方牵引两种方式对于上颌骨位置改变的疗效以及对于上前牙稳定性的比较,探讨更适合的治疗方法。方法选取山西医科大学口腔医院正畸科就诊的20例安氏Ⅲ类错(牙合)畸形的患者,并随机分为扩缩组与未扩缩组,扩缩组先反复扩缩8周,8周后与未扩缩组同时开始前方牵引,3个月后分析比较治疗前后的头影测量指标。结果扩缩组治疗后SNA、ANB、U1-SN、MP-SN、UL-EP值均增大,差异均有统计学意义(P<0.05);未扩缩组治疗后SNA、ANB、U1-SN、MP-SN、UL-EP值均增大,差异均有统计学意义(P<0.05);两组患者治疗前后SNA、ANB、U1-SN、MP-SN、UL-EP的变化大小不同,差异有统计学意义(P<0.05),扩缩组的变化程度高于未扩缩组;扩缩组上前牙唇舌向的动度仅与治疗前后ANB变化程度的等级相关系数有统计学意义,二者呈正相关关系,其余测量值与动度无相关性。结论替牙期骨性Ⅲ类错(牙合)畸形前方牵引前先进行反复扩缩较直接进行前方牵引有较好的临床疗效,但会引起上前牙一定程度的松动。

Objective To compare the effects of alternate rapid maxillary expansion and constriction before maxillary traction and direct anterior traction in the early permanent dentition skeletal Class Ⅲ, simultaneously compare the stability of upper anterior teeth and accordingly explore a more suitable treatment method. Methods Twenty patients with Class Ⅲ malocclusion were selected from the Department of Orthodontics, Stomatology Hospital of Shanxi Medical University. They were randomly divided into an expansion and contraction group and unexpanded group. The sample in expansion and contraction group was repeatedly expanded for 8 weeks. 8 weeks later, the anterior traction was started at the same time as the unexpanded group, the cephalometric measurement indicators before and after treatment were analyzed and compared after 3 months. Results The values of SNA, ANB, U1-SN, MP-SN and UL-EP increased after treatment in the expansion group(P<0.05). The values of SNA, ANB, U1-SN, MP-SN and UL-EP all increased after treatment in the non-expanded group, and the differences were statistically significant(P<0.05). The changes of SNA, ANB, U1-SN, MP-SN and UL-EP before and after treatment in the two groups were different. The difference was statistically significant(P<0.05). The degree of change in the expansion and contraction group was higher than that in the non-expanded group. The correlation between the anterior teeth and the lingual direction of the expansion and contraction group was only significantly related to the degree of ANB change before and after treatment. The two were positively correlated, while the other measurements were not related to the mobility. Conclusion Repeated expansion and contraction of the skeletal Class Ⅲ malocclusion before volition in the dentition period has a better clinical effect than direct anterior traction, but it will cause a certain degree of loosening of the upper anterior teeth.