NCT07485478

Effects of Invisalign Palatal Expander vs Rapid Palatal Expander With Facemask in Growing Class III Patients

Effects of the Invisalign® Palatal Expander (IPE) vs. Rapid Palatal Expander With Facemask in Growing Skeletal Class III Patients: A CBCT Randomized Clinical Trial

• Status: Not Yet Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 24 (estimated)
• Sponsor: Mahidol University · Academic / Other
• Sex: All
• Age: 8 Years – 12 Years
• Healthy volunteers: Not accepted

Summary

The goal of this clinical trial is to compare two types of palatal expanders used with a facemask in children who have skeletal Class III and a narrow upper jaw. The study will compare the Invisalign Palatal Expander (IPE) and the Rapid Palatal Expander (RPE). Researchers want to learn how these devices affect jaw bones and tooth position. They also want to learn about children's and parents' experiences during treatment. The main questions this study aims to answer are: Do IPE and RPE widen the upper jaw differently? Do they cause different changes in tooth position? How do children and parents describe their treatment experience? Participants will be children aged 8 to 12 years who have skeletal Class III and a narrow upper jaw. Children with craniofacial conditions, previous upper jaw expansion, or medical conditions that prevent orthodontic treatment will not take part. Parents and children must give consent before joining the study. Participants will: Be assigned to receive either IPE or RPE Expand the upper jaw to 7 mm (0.25 mm per day) After expansion, wear a facemask for at least 12 hours per day for 6 to 8 months Have cone-beam computed tomography (CBCT) scans taken before expansion, after expansion, and after facemask treatment Take part in an interview with a parent after expansion Researchers will use CBCT images to measure changes in jaw bones and tooth position. The main outcomes are changes in jaw bones and tooth position. Secondary outcomes include children's and parents' experiences during treatment.

Conditions

• Skeletal Class III Malocclusion
• Transverse Maxillary Deficiency

Interventions

Type	Name	Description
DEVICE	Invisalign Palatal Expander (IPE)	Participants will be treated with an Invisalign palatal expander. Participants will be instructed to wear the appliance full-time, except when brushing and flossing their teeth, and to change the device daily (0.25 mm) until the planned transverse width (7 mm.) is achieved.
DEVICE	Rapid Palatal Expander (RPE)	Participants will be treated with a bonded RPE. Their parents are instructed to activate the screw once per day (0.25 mm) until the expansion screw reaches 7 mm.

Timeline

• Start date: 2026-03-01
• Primary completion: 2027-06-01
• Completion: 2027-10-01
• First posted: 2026-03-20
• Last updated: 2026-03-20

Locations

1 site across 1 country: Thailand

Regulatory

• FDA-regulated device study