不同正畸力对上颌尖牙移动速率影响的分析

目的:通过测量上颌尖牙在不同时间内不同正畸力值作用下牙齿移动的距离,探索牙齿移动和最适力的关系。方法:选取32例处于生长发育期的患者为研究对象,随机分成4组。依组别分别对其上颌右侧的尖牙给予50、100、150、250 g的远中移动的初始力。对侧尖牙不加力,为对照组。测量不同时间内全部样本左右侧尖牙移动的距离。结果:尖牙受力后不同时间内牙齿移动速率不同,有统计学意义(P<0.01),不同力值作用下的各组牙齿移动速率也不同(P<0.01),二者有交互作用。结论:对于上颌尖牙,当正畸加载力小于100 g时,移动速率随着力值的增大而不断增加。但当超过100 g后,随着力值的增加,牙齿移动速率增加不明显。

Analysis of Maxillary Canine Movement Speed under Different Orthodontic Forces.

Objective: To provide the reference standard of suitable force for clinics through measuring the distance of maxillary canine movement under different durations and different forces. Methods: Thirty-two cases under the growth and development period were divided into 4 groups. Different orthodontic distal forces (50g, 100g, 150g and 200g) were pressured on the maxillary canine of right side in different groups. No force was pressured on the maxillary canine of left side. The moving distances of the whole canines were measured during different time periods. Results: The movement speeds of maxillary canine were significantly different during different time periods (P<0.01). The movement speeds were also significantly different under different forces (P<0.01). Interaction was present between force and time. Conclusion: The movement speeds of maxillary canine increased following the increased forces when the force was less than 100g. However, the movement speeds did not increase dramatically when the force was more than 100g.