Treatment effects and lip profile changes following premolars extraction treatment vs fixed functional treatment in Class II division 1 malocclusion: A randomized controlled clinical trial

ABSTRACT Objective: The objective of this two-arm parallel randomized controlled trial was to evaluate the treatment effects and lip profile changes in skeletal Class II patients subjected to premolars extraction treatment versus fixed functional treatment. Methods: Forty six subjects fulfilling inclusion criteria were randomly distributed into Group PE (mean age 13.03±1.78 years) and Group FF (mean age 12.80±1.67 years) (n=23 each). Group PE was managed by therapeutic extraction of maxillary first premolars and mandibular second premolars, followed by mini-implant-supported space closure; and Group FF, by fixed functional appliance therapy. Skeletal, dental, and soft-tissue changes were analyzed using pre and post-treatment lateral cephalograms. Data obtained from this open label study was subjected to blind statistical analysis. Results: Extraction treatment resulted in greater increase of nasolabial angle (NLA: 3.1 [95% CI 2.08, 4.19], p

摘要：本研究旨在通过一项双臂平行随机对照试验，评估在拔除前磨牙治疗与固定功能性治疗下，接受治疗的骨骼II类患者的治疗效果及唇部轮廓的变化。方法：符合纳入标准的46名受试者被随机分配至PE组（平均年龄13.03±1.78岁）和FF组（平均年龄12.80±1.67岁）（每组23人）。PE组通过治疗性拔除上颌第一前磨牙和下颌第二前磨牙，随后进行迷你植入体支持的间隙关闭来管理；而FF组则通过固定功能性矫正器治疗。通过治疗前后的侧面头影测量图分析了骨骼、牙齿和软组织的改变。该开放标签研究获得的数据接受了盲法统计分析。结果：拔牙治疗导致鼻唇角（NLA：3.1 [95% CI 2.08, 4.19], p