Efficacy of Mini-implant Assisted Maxillary Expansion in Adolescents and Adults

NCT ID: NCT06449014

Last Updated: 2025-08-11

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 60 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-10-02
• Study Completion Date: 2027-09-30

Brief Summary

Transverse maxillary deficiency is a common orthodontic issue, affecting around 10% of adults. Late adolescents and adults often require more force to expand the midpalatal suture due to its increased interdigitation. This study aims to assess the effectiveness of MARPE in this demographic and determine the best activation protocol for non-surgical maxillary expansion using mini-screw-supported appliances. Additionally, the study will evaluate the effectiveness of MARPE on nasal permeability and airway volume.

Detailed Description

The study design comprised a three-arm, parallel-group randomized controlled trial (RCT) conducted at the Orthodontics clinic of Brussels University Hospital. Patients were randomly allocated into one of three groups:

1. Continuous rapid activation protocol: Patients received one activation of 0.17 mm per day until reaching the clinical goal.

2. Continuous slow activation protocol: Patients underwent two activations (0.33 mm) per day for the first 7 days, followed by one turn forward every third day (0.17 mm / 3 days).

3. Force-controlled polycyclic protocol: Patients underwent two activations (0.33 mm) per day for the first 7 days. Then, the hex nut was turned 6 sides backward, followed by 6 sides forward after 15 minutes. Additionally, the device was activated by 0.17 mm every third day.

Intervention:

All patients underwent maxillary expansion with MARPE. Four orthodontic mini-screws were inserted under local anesthesia using a surgical guide and motor. Surgical incision was not required, and predrilling was performed if necessary. The MARPE remained in place for 12 months after expansion to allow bone remodeling in the midpalatal suture. Fixed straight-wire treatment commenced 2 months after expansion termination. Patients underwent retention check-ups at 6 and 12 months post-expansion, and expansion screws and mini-screws were removed after 12 months or before orthognathic surgery, if applicable.

The specific aims of the study were to evaluate the success rate of nonsurgical maxillary expansion, compare the efficacy of the three activation protocols, assess and compare complications, analyze the correlation between success rate and Midpalatal Suture Maturation Stage (MPS), age, and sex, and measure nasal permeability variation using anterior rhinomanometry.

Conditions

Narrow Maxilla

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

CRAP

Continuous Rapid Activation Protocol: 1 activation of the expansion screw per day which is equal to 0,17 mm expansion of the maxilla per day till reaching the clinical goal

Group Type: EXPERIMENTAL

Mini-implants assisted maxillary expansion

Intervention Type: DEVICE

The intervention involved the placement of orthodontic mini-screws in the patient's palate, varying in diameter from 2 to 2.3 mm and in length from 11 to 15 mm. After mini-screw insertion, another intraoral scan was taken for the fabrication of the appliance. Approximately three weeks later, the expander was placed in the patient's palate, and maxillary expansion was initiated immediately afterward according to the chosen protocol.

SCAP

Continuous Slow Activation Protocol: 2 activations of the expansion screw which is equal to 0,33 mm expansion of the maxilla per day during the first 7 days. After that first week, then each third day 1 activation (0,17 mm / 3 days).

Group Type: EXPERIMENTAL

Mini-implants assisted maxillary expansion

Intervention Type: DEVICE

The intervention involved the placement of orthodontic mini-screws in the patient's palate, varying in diameter from 2 to 2.3 mm and in length from 11 to 15 mm. After mini-screw insertion, another intraoral scan was taken for the fabrication of the appliance. Approximately three weeks later, the expander was placed in the patient's palate, and maxillary expansion was initiated immediately afterward according to the chosen protocol.

FCPC

force-controlled polycyclic protocol: 2 activations of the expansion screw which is equal to 0,33 mm expansion of the maxilla per day during the first 7 days. Then the expansion screw will be turned 6 sides backward, and after 15 min, the expansion screw will be turned forward 6 sides again. And every third day, the device will be additionally activated by 0.17mm (0,17 mm / 3 days)

Group Type: EXPERIMENTAL

Mini-implants assisted maxillary expansion

Intervention Type: DEVICE

The intervention involved the placement of orthodontic mini-screws in the patient's palate, varying in diameter from 2 to 2.3 mm and in length from 11 to 15 mm. After mini-screw insertion, another intraoral scan was taken for the fabrication of the appliance. Approximately three weeks later, the expander was placed in the patient's palate, and maxillary expansion was initiated immediately afterward according to the chosen protocol.

Interventions

Mini-implants assisted maxillary expansion

The intervention involved the placement of orthodontic mini-screws in the patient's palate, varying in diameter from 2 to 2.3 mm and in length from 11 to 15 mm. After mini-screw insertion, another intraoral scan was taken for the fabrication of the appliance. Approximately three weeks later, the expander was placed in the patient's palate, and maxillary expansion was initiated immediately afterward according to the chosen protocol.

Intervention Type: DEVICE

Other Intervention Names

Mini-screws assisted maxillary expansion; Mini-implants assisted rapid maxillary expansion

Eligibility Criteria

Inclusion Criteria

• from the age of 16 onwards
• who presented with transverse maxillary discrepancy (unilateral, bilateral, anticipated, or constriction without crossbite).

Exclusion Criteria

• history or presence of maxillofacial surgery, cleft lip and palate, craniofacial anomalies or syndromes, congenital tooth anomalies, and periodontal disease.
• Patients who had previously palatal expansion were excluded also.
• Presence of anatomic or pathological obstacle of the palatal mini-screw insertion (impacted tooth, tumor.)
• refusal of study participation

• Minimum Eligible Age: 16 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Erasme University Hospital

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Route de Lennik 900

Anderlecht, Brussels Capital, Belgium

Site Status: NOT_YET_RECRUITING

service dentaire et d'orthodontie de l'hopital université de bruxelles (HUB)

Anderlecht, Brussels Capital, Belgium

Site Status: RECRUITING

Countries

Belgium

Central Contacts

arnel NANA, Dr

Role: CONTACT

narnelredon@gmail.com

+32460952160

Facility Contacts

Fairouz BEN ABDELOUAHED, Dr

Role: primary

f.benabdelouahed@hubruxelles.be

+32487262857

Fairouz BEN ABDELOUAHED, Dr

Role: primary

f.benabdelouahed@hubruxelles.be

+32 487262857

Other Identifiers

Erasme_MARPE_1

Identifier Type: -

Identifier Source: org_study_id