正畸治疗后牙弓稳定性的追踪研究

The study on stability in dental arch out of retention of orthodontic treatment

目的 探讨正畸治疗后牙弓的稳定性。方法 对正畸治疗后 2～ 8年 74例错牙合畸形患者治疗前后及保持后模型进行牙弓测量。结果 保持后 ,上基骨宽度较治疗后增加 2 .11% ;上下 6～ 6宽度、下基骨宽度没有显著性变化 ,其余均出现明显减少 ;减少百分率最大依次为上下 3 - 3长度 ( 7.79% ,7.5 6 % )、上下基骨长度( 7.14% ,5 .12 % )、上下牙弓长度 ( 3 .91% ,3.37% )、上下 3 - 3宽度 ( 2 .2 8% ,3 .30 % )。结论 保持停止后 ,上下牙弓长度、基骨长度及 3- 3宽度有不断减少和 3 - 3长度有回复治疗前水平的倾向 ,而 6 - 6宽度较稳定。

ObjectiveTo investigate stability in dental arch out of retention of orthodontic treatment.MethodsThe dental arches were measured on Pre-,post-treatment and 2-8year out of retention study models of 74 cases with malocclusions.ResultsOut of retention, there was a significant increase in upper basal bone width( 2.11%) and no significant change in lower basal bone width and intermolar width on both jaws,whereas there was a significant decrease among others.Percentage reduction from more to less was intercanine length( 7.79%, 7.56%),basal bone length( 7.14%, 5.12%),dental arch length( 3.91%, 3.37%),intercanine width( 2.28%, 3.30%) on both jaws.ConclusionThere was a trend in continuing decrease in dental arch length, basal bone length and intercanine width and relapsing to pre-treatment original position in intercanine length,whereas intermolar width was more stable out of retention.