Clear Aligners vs Fixed Appliances for Molar Distalization Using Infrazygomatic Crest Screws

NCT07714603 | Completed

• 1 other identifier: TDH-2025-15402
• Study Type: interventional
• Target: 37
• Locations: 1 country
• Sites: 1

Brief Summary

This study compares three different methods of moving upper back teeth backward (distalization) to create space for crowded or protruding teeth, all supported by small temporary screws placed in the cheekbone area (infrazygomatic crest screws). Participants were randomly assigned to one of three treatment types: traditional fixed braces (Pitts21 system), Invisalign clear aligners, or ClearCorrect clear aligners. The study measures how effectively each method moves the back teeth, how long treatment takes, and how comfortable and practical each method is for patients. The goal is to help orthodontists and patients choose the most effective and efficient treatment option for this type of tooth movement.

Conditions

Angle Class 2 Malocclusion

Keywords

Clear aligners; Fixed orthodontic appliance; Distalization; Infrazygomatic crest miniscrew; Skeletal anchorage

Outcome Measures

Primary Outcomes (1)

• Amount of Maxillary Posterior Tooth Distalization

  The amount of distalization of the maxillary premolars and molars (U4, U5, U6, U7) was measured in millimeters using three-dimensional digital dental model analysis, comparing pre-treatment (T0) and post-distalization (T1) records.

  From the date of infrazygomatic crest miniscrew placement and initiation of distalization force (T0) until the end of the active distalization phase (T1), assessed up to 13 months

Secondary Outcomes (1)

• Total Distalization Duration

  From the date of miniscrew placement and start of distalization force (T0) until the date of completion of active distalization (T1), assessed up to 13 months

Other Outcomes (8)

• Distalization Efficacy in Clear Aligner Groups

  From treatment planning (T0) until the end of active distalization (T1), assessed up to 13 months

• Infrazygomatic Crest Miniscrew Success Rate

  From the date of miniscrew placement until the end of active distalization, assessed up to 13 months

• Cephalometric Skeletal, Dental, and Soft Tissue Changes

  From the date of miniscrew placement and start of distalization force (T0) until the end of active distalization (T1), assessed up to 13 months

Study Arms (3)

Group A ( Pitts21® Fixed Appliance )

ACTIVE COMPARATOR

Participants received maxillary posterior distalization using the Pitts21® fixed orthodontic appliance system, anchored with infrazygomatic crest (IZC) miniscrews and intraoral elastics for distalization force.

Device: Pitts21® fixed appliance

Group B ( Invisalign® clear aligners)

EXPERIMENTAL

Participants received maxillary posterior distalization using Invisalign® clear aligners, anchored with infrazygomatic crest (IZC) miniscrews and intraoral elastics for distalization force.

Device: Invisalign® Clear Aligners

Group C ( ClearCorrect® clear aligners)

EXPERIMENTAL

Participants received maxillary posterior distalization using ClearCorrect® clear aligners, anchored with infrazygomatic crest (IZC) miniscrews and intraoral elastics for distalization force.

Device: ClearCorrect Clear Aligners

Interventions

Invisalign® Clear Aligners DEVICE

Clear aligner system (Invisalign) used for maxillary posterior distalization, anchored with infrazygomatic crest miniscrews and intraoral elastics.

Also known as: Invisalign Clear Aligner System

Group B ( Invisalign® clear aligners)

Pitts21® fixed appliance DEVICE

Fixed orthodontic brackets (Pitts21 system) used for maxillary posterior distalization, anchored with infrazygomatic crest miniscrews and intraoral elastics.

Also known as: Fixed orthodontic bracket system

Group A ( Pitts21® Fixed Appliance )

ClearCorrect Clear Aligners DEVICE

Clear aligner system (ClearCorrect) used for maxillary posterior distalization, anchored with infrazygomatic crest miniscrews and intraoral elastics.

Also known as: ClearCorrect Clear Aligner System

Group C ( ClearCorrect® clear aligners)

Eligibility Criteria

• Age: 13 Years - 18 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Skeletal Class I (ANB angle 0-4°), dental Class II malocclusion treatable with molar distalization
• Need for unilateral or bilateral distalization of the first molars in the range of 2-4.5 mm
• Chronological age between 13 and 18 years, regardless of skeletal age
• Normal or hypodivergent growth pattern (SN-GoGn \< 39°)
• Mild to moderate maxillary crowding (less than 6 mm) and minimal or no mandibular crowding (less than 3 mm)
• No previously extracted maxillary teeth, excluding third molars
• Erupted permanent second molars
• Good oral hygiene
• Healthy periodontal tissues

You may not qualify if:

• Need for orthodontic tooth extraction or functional appliance therapy
• Presence of systemic disease
• Congenital or acquired craniofacial deformity involving the condyle or mandible
• Poor patient cooperation
• History of allergy to any metal
• Pre-existing root resorption prior to treatment
• Previous orthodontic treatment
• Abnormal position, depth of impaction, or close proximity to adjacent anatomical structures (sinus, neurovascular structures) of the maxillary third molar that would make its surgical extraction risky

Sponsors & Collaborators

• TC Erciyes University: lead

Study Sites (1)

Erciyes University, Faculty of Dentistry, Department of Orthodontics

Kayseri, 38000, Turkey (Türkiye)

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Prof. Dr.

Model Details: Participants were randomly assigned to one of three parallel groups: Pitts21® fixed orthodontic system, Invisalign® clear aligner system and ClearCorrect® clear aligner system.

Study Record Dates

• First Submitted: July 15, 2026
• First Posted: July 20, 2026
• Study Start: June 6, 2024
• Primary Completion: January 12, 2026
• Study Completion: February 18, 2026
• Last Updated: July 20, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)