Leaf Expander Versus Hyrax Expander in Mixed Dentition Patients With Posterior Crossbite.

NCT07301918 | Recruiting DMC

• 1 other identifier: 24619942
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Design: Two-arm parallel randomized clinical trial in mixed dentition (6-12 years). Arms: (1) 9 mm, 900 g leaf expander; (2) 9 mm Hyrax expander. Follow-up: From appliance insertion → completion of intended expansion → 6-month retention. Primary outcome: Pain perception during the first 7 days post-insertion (daily patient-reported scale). Secondary outcomes: Skeletal and dental changes on CBCT.

Conditions

Posterior Crossbite; Maxilla; Hypoplasia

Keywords

expander; maxillary transverse deficiency; posterior crossbite; mixed dentition

Outcome Measures

Primary Outcomes (1)

• Pain perception

  Pain perception during the first week after insertion using Wong-Becker faces scale with minimum value of zero and maximum value of ten, ten score represents the worst pain percieved.

  first week after appliance insertion

Secondary Outcomes (2)

• skeletal expansion

  6 months post expansion

• dental tipping

  6 months post-expansion

Study Arms (2)

Banded Leaf expander supported on the maxillary first permanent molars

EXPERIMENTAL

9mm leaf expander delievering 900 gm force will be supported on the upper first permanent molars with the appliance arm extending to the canines

Device: The Leaf expander

Banded Hyrax expander supported on the maxillary first permanent molars

ACTIVE COMPARATOR

9mm Hyrax expander will be supported on the upper first permanent molars with the appliance arm extending to the canines

Device: Hyrax expander

Interventions

The Leaf expander DEVICE

The Leaf expander incorporates Nickel Titanium springs that will not require the patients' home activation

Banded Leaf expander supported on the maxillary first permanent molars

Hyrax expander DEVICE

Hyrax expander incorporates a screw that requires the patients' home activation

Banded Hyrax expander supported on the maxillary first permanent molars

Eligibility Criteria

• Age: 6 Years - 12 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• Male and female patients
• Mixed dentition stage
• Unilateral or bilateral posterior crossbite.
• Patients in prepubertal stage with cervical vertebral maturation stage 1-3.
• Fully erupted maxillary and mandibular permanent first molars.
• Skeletal class I or II.

You may not qualify if:

• Previous orthodontic treatment.
• Missing teeth.
• Inadequate oral hygiene.
• Patients with bad oral habits.
• Patients with medical conditions.
• Patients with cleft lip and palate.

Sponsors & Collaborators

• Cairo University: lead

Study Sites (1)

Cairo University

Cairo, Egypt

RECRUITING

MeSH Terms

Conditions

Retrognathia

Condition Hierarchy (Ancestors)

Jaw Abnormalities; Jaw Diseases; Musculoskeletal Diseases; Maxillofacial Abnormalities; Craniofacial Abnormalities; Musculoskeletal Abnormalities; Stomatognathic Diseases; Mandibular Diseases; Stomatognathic System Abnormalities; Congenital Abnormalities; Congenital, Hereditary, and Neonatal Diseases and Abnormalities

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: statistician
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal investigator

Study Record Dates

• First Submitted: November 21, 2025
• First Posted: December 24, 2025
• Study Start: October 1, 2025
• Primary Completion (Estimated): March 1, 2027
• Study Completion (Estimated): March 1, 2027
• Last Updated: March 18, 2026

Record last verified: 2025-10

Locations

EG (1)