NCT06609733

Comparative Effect of Clear Aligner Mandibular Advancement and Twin Block Appliances in Class II Malocclusion

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 47 (actual)
• Sponsor: Sichuan University · Academic / Other
• Sex: All
• Age: 10 Years – 13 Years
• Healthy volunteers: Not accepted

Summary

The goal of this retrospective observational study is to compare the effects of Clear Aligner Mandibular Advancement (MA) and Twin Block (TB) appliances in treating Class II malocclusion, a condition where the lower jaw is underdeveloped. The main questions it aims to answer are: 1. Does mandibular advancement with clear aligners improve jaw and dental alignment as effectively as Twin Block appliances? 2. What are the differences in soft tissue changes, such as chin advancement and lip position, between these two treatments? Researchers will compare MA and TB appliances to an untreated control group to evaluate their impact on skeletal, dental, and soft tissue outcomes. Participants in the study underwent cephalometric analysis (X-ray measurements) both before and after treatment to assess changes in jaw positioning, overbite, and overjet. The study focuses on how each treatment affects facial aesthetics and dental function. Participants in the study will: * Undergo treatment with either clear aligner mandibular advancement or Twin Block appliances. * Attend follow-up appointments to monitor progress and assess treatment outcomes.

Detailed description

Supplementary information for Study Design It was a retrospective study that collected patients' routine treatment X-rays (before and after treatment) to measure some angular and linear parameters from the X-rays.

Conditions

• CLASS II DIVISION 1 MALOCCLUSION

Interventions

Type	Name	Description
DEVICE	Twin block	The TB group used a single appliance continuously, with appropriate reduction of occlusal surface height by 1 mm when clinically indicated. Both groups had follow-up appointments every 6 weeks.
DEVICE	Clear aligner with mandibular function	The MA group underwent stepwise mandibular forward movement with clear aligners (Invisalign, Align Inc, CA, USA) worn for 22 hours/day and replaced every 7 days.

Timeline

• Start date: 2021-08-01
• Primary completion: 2022-08-01
• Completion: 2024-06-30
• First posted: 2024-09-24
• Last updated: 2024-09-24

Locations

1 site across 1 country: China

Regulatory

• FDA-regulated device study