Comparison Between Mandibular Advancement With Aligners and Twin Block in Class II Malocclusion in Growing Patients

NCT07591025 | Completed

• 1 other identifier: UniversidadDeSalamanca
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

To analyze mandibular advancement between the traditional Twin Block and the Angel Aligner A6 mandibular advancement clear aligners using cephalometric analysis in growing patients and a repeatable and reproducible digital measurement technique.

Conditions

Malocclusion Class II

Keywords

Class II; mandibular advancement; clear aligners; twin block; growing patients

Outcome Measures

Primary Outcomes (2)

• ANB (°)

  Point A-nasion-point B angle (ANB): relationship between the upper and lower jaws

  10 months

• Wits appraisal (AO-BO)

  projecting points A and B in two perpendicular lines, along the functional occlusal plane

  10 months

Study Arms (3)

AngelAligner A6 Mandibular Advancer

EXPERIMENTAL

Mandibular advancement with aligners uses specially designed appliances to position the lower jaw forward, improving jaw alignment and correcting Class II malocclusion in growing patients. Aligner replacement was performed at 10-day intervals.

Device: AngelAligner A6 Mandibular Advancer

Twin block

ACTIVE COMPARATOR

The Twin Block is a removable functional orthodontic appliance used to correct Class II malocclusion by advancing the mandible. It consists of upper and lower acrylic plates with bite blocks that interlock at a specific angle, guiding the lower jaw forward during closure. It is most effective in growing patients to improve jaw relationship and facial profile. The Twin Block appliance was worn for a period of 10 months, with a minimum of 14-16 hours per day, including night hours.

Device: Twin Block

Clear aligners

ACTIVE COMPARATOR

Class II correction with aligners (without mandibular advancement) involves the use of clear sequential aligners to improve dental alignment and occlusion by moving teeth into a more favorable position. The correction is achieved through controlled tooth movements without actively repositioning the mandible forward. Aligner replacement was performed at 10-day intervals.

Device: Clear aligners

Interventions

AngelAligner A6 Mandibular Advancer DEVICE

Mandibular advancement with aligners is achieved using specially designed orthodontic aligners that incorporate built-in mandibular advancement features. These appliances posture the lower jaw forward in a controlled and incremental manner while simultaneously aligning the teeth. The forward positioning of the mandible helps stimulate mandibular growth in growing patients and improves the correction of Class II malocclusion by enhancing sagittal jaw relationship. Aligner replacement was performed at 10-day intervals.

Also known as: GA6

AngelAligner A6 Mandibular Advancer

Twin Block DEVICE

The Twin Block is a removable functional orthodontic appliance used to correct Class II malocclusion by advancing the mandible. It consists of upper and lower acrylic plates with bite blocks that interlock at a specific angle, guiding the lower jaw forward during closure. It is most effective in growing patients to improve jaw relationship and facial profile. The Twin Block appliance, used for mandibular advancement (correction of skeletal class II), was usually worn for a period of 10 months, with a minimum of 14-16 hours per day, including night hours.

Twin block

Clear aligners DEVICE

Class II correction with aligners (without mandibular advancement) involves the use of clear sequential aligners to improve dental alignment and occlusion by moving teeth into a more favorable position. The correction is achieved through controlled tooth movements such as distalization, interproximal reduction, and vertical control, without actively repositioning the mandible forward.

Clear aligners

Eligibility Criteria

• Age: 9 Years - 14 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• Aged between 9 and 14 years with late mixed or early permanent dentition
• Class II/1 malocclusion (molar relationship ≥ half-cusp Class II and overjet ≥ 5 mm)
• ANB angle greater than 5º
• SNB lower than 78º
• CVMS 2-3, a growing patients.

You may not qualify if:

• Previous orthodontic treatment or orthognathic surgery
• Patients with severe malformations or syndromes
• Extraction treatment.

Sponsors & Collaborators

• University of Salamanca: lead

Study Sites (1)

University of Salamanca

Salamanca, Salamanca, 37008, Spain

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: The study is designed as a parallel-group interventional trial with three independent treatment arms. A total of 60 participants (mean age: 12.4 ± 1.3 years) will be enrolled and allocated equally into one of three orthodontic interventions (Twin Block, standard Angel Aligner, or Angel Aligner A6 with mandibular advancement), with 20 patients per group. Each participant receives only the assigned treatment throughout the study period, with no crossover between groups. Outcomes are assessed at baseline (T0) and after 10 months of treatment (T1) using digital cephalometric analysis.

Study Record Dates

• First Submitted: May 6, 2026
• First Posted: May 15, 2026
• Study Start: October 18, 2022
• Primary Completion: October 18, 2022
• Study Completion: July 14, 2025
• Last Updated: May 15, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

ES (1)