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

NCT06609733 | Completed DMC FDA Device

• 1 other identifier: WCHS-IRB-CT-2023-195
• Study Type: observational
• Target: 47
• Locations: 1 country
• Sites: 1

Brief 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:

• Undergo treatment with either clear aligner mandibular advancement or Twin Block appliances.
• Attend follow-up appointments to monitor progress and assess treatment outcomes.

Conditions

CLASS II DIVISION 1 MALOCCLUSION

Outcome Measures

Primary Outcomes (4)

• Changes in Skeletal Measurements ( SNB angle)

  This study assesses skeletal changes in patients treated for Class II malocclusion with Twin Block (TB) or Mandibular Advancement (MA) appliances at West China School of Stomatology, Sichuan University. The evaluation focuses on the measurement of the SNB angle, a critical skeletal parameter, using cephalometric radiographs. These radiographs are taken as a routine part of the treatment to capture skeletal positioning before the treatment starts and after the treatment concludes. This allows for an analysis of the angular changes due to the orthodontic intervention, providing insights into the effectiveness of the appliances in correcting malocclusions.

  Baseline and post-treatment cephalometric radiographs will be taken 1-2 weeks pre and 1-2 weeks post the 12-month treatment at West China School of Stomatology, Sichuan University.

• Changes in Soft Tissue Measurements ( soft tissue chin thickness)

  This study assesses skeletal changes in patients treated for Class II malocclusion with Twin Block (TB) or Mandibular Advancement (MA) appliances at West China School of Stomatology, Sichuan University. The evaluation focuses on the measurement of the soft tissue chin thickness, using cephalometric radiographs. These radiographs are taken as a routine part of the treatment to capture skeletal positioning before the treatment starts (baseline) and after the treatment concludes (1-2 weeks post the 12-month treatment). This allows for an analysis of the angular changes due to the orthodontic intervention, providing insights into the effectiveness of the appliances in correcting malocclusions.

  Baseline and post-treatment cephalometric radiographs will be taken 1-2 weeks pre and 1-2 weeks post the 12-month treatment at West China School of Stomatology, Sichuan University.

• Changes in Skeletal Measurements (ANB angle)

  This study assesses skeletal changes in patients treated for Class II malocclusion with Twin Block (TB) or Mandibular Advancement (MA) appliances at West China School of Stomatology, Sichuan University. The evaluation focuses on the measurement of the ANB angle, a critical skeletal parameter, using cephalometric radiographs. These radiographs are taken as a routine part of the treatment to capture skeletal positioning before the treatment starts and after the treatment concludes. This allows for an analysis of the angular changes due to the orthodontic intervention, providing insights into the effectiveness of the appliances in correcting malocclusions.

  Baseline and post-treatment cephalometric radiographs will be taken 1-2 weeks pre and 1-2 weeks post the 12-month treatment at West China School of Stomatology, Sichuan University.

• Changes in Skeletal Measurements ( mandibular length)

  This study assesses skeletal changes in patients treated for Class II malocclusion with Twin Block (TB) or Mandibular Advancement (MA) appliances at West China School of Stomatology, Sichuan University. The evaluation focuses on the measurement of the mandibular length (mm), a critical skeletal parameter, using cephalometric radiographs. These radiographs are taken as a routine part of the treatment to capture skeletal positioning before the treatment starts and after the treatment concludes. This allows for an analysis of the angular changes due to the orthodontic intervention, providing insights into the effectiveness of the appliances in correcting malocclusions.

  Baseline and post-treatment cephalometric radiographs will be taken 1-2 weeks pre and 1-2 weeks post the 12-month treatment at West China School of Stomatology, Sichuan University

Study Arms (2)

MA group

Patients receiving routine care for Class II malocclusion, which may include the use of Clear Aligner with Mandibular Advancement (MA) function appliances

Device: Clear aligner with mandibular function

TB group

Patients receiving routine care for Class II malocclusion, which may include the use of Twin Block (TB) appliances

Device: Twin block

Interventions

Twin block DEVICE

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.

TB group

Clear aligner with mandibular function DEVICE

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.

MA group

Eligibility Criteria

• Age: 10 Years - 13 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)
• Sampling Method: Non-Probability Sample

Study Population

The study population consists of patients from the Orthodontics Department at West China Hospital of Stomatology, Sichuan University. This population includes individuals diagnosed with Class II malocclusion who are undergoing or have completed treatment with Mandibular Advancement (MA) or Twin Block (TB) appliances. Eligible participants for the treatment group are those in the mixed dentition or early permanent dentition stages, showing specific cephalometric characteristics such as an ANB angle greater than 4 degrees and an SNB angle less than or equal to 78 degrees.

You may qualify if:

• Patients who have completed MA or TB treatment at the West China Hospital of Stomatology Orthodontic Department.
• Pretreatment lateral cephalometric radiographs showing cervical vertebral maturation stage (CVSM) II or III.
• Patients in the mixed dentition or early permanent dentition stages.
• Class II Division 1 malocclusion according to Angle's classification
• ANB angle \> 4°; SNB ≤ 78°.
• Comprehensive medical records and necessary data available pre- and post-treatment.

You may not qualify if:

• Missing teeth, supernumerary teeth, or severe dental malformations affecting function.
• Poor oral hygiene.
• Systemic diseases or congenital deformities.
• History of dental or maxillofacial trauma.
• Incomplete or missing records.

Sponsors & Collaborators

• Sichuan University: lead

Study Sites (1)

West China School of Stomatology, Sichuan University

Chengdu, Sichuan, 610041, China

Location

Related Publications (1)

• Alsaggaf DH, Afify AR, Zawawi KH, Alsulaimani FF. Factors influencing the orthodontic treatment plan in Class II malocclusion. Am J Orthod Dentofacial Orthop. 2022 Jun;161(6):829-837.e1. doi: 10.1016/j.ajodo.2021.01.034. Epub 2022 Jan 29.

  PMID: 35094890 BACKGROUND

MeSH Terms

Conditions

Malocclusion, Angle Class II

Condition Hierarchy (Ancestors)

Malocclusion; Tooth Diseases; Stomatognathic Diseases

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor and Vice Director

Study Record Dates

• First Submitted: September 16, 2024
• First Posted: September 24, 2024
• Study Start: August 1, 2021
• Primary Completion: August 1, 2022
• Study Completion: June 30, 2024
• Last Updated: September 24, 2024

Record last verified: 2024-09

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)