Effectiveness of Rapid and Slow Maxillary Expansion in Treating Posterior Crossbite

Not Applicable

Completed

• Conditions: Posterior Crossbite
• Interventions: Procedure: Slow Maxillary Expanding Device; Procedure: Rapid Maxillary Expanding Device

• Registration Number: NCT03667508
• Lead Sponsor: Damascus University

Brief Summary

This study will evaluate the efficacy of rapid maxillary expansion (RME) and slow maxillary expansion (SME) in treating posterior crossbite using cone beam computed tomography.

The study sample will consist of 32 patients who suffer from a skeletal posterior crossbite. The sample will be allocated randomly into two groups: RME group and SME group.

The skeletal and dento-alveolar changes occurring after treatment will be assessed by using cone beam computed tomography(CBCT) radiographs.

Detailed Description

Unilateral or bilateral posterior crossbite (PXB) is a common malocclusion. In recent decades, RME has gained preference as the treatment of choice for PXB. However, the side effects, such as reported pain, relapse of the expansion, tipping of the molars, bone loss, gingival recession, and root resorption, have lead some clinicians to prefer SME.

In this study the investigators will treat PXB using two techniques, RME and SME. Patients will be divided into two groups (a technique in each group) to evaluate the efficacy of each one using cone beam computed tomography.

RME group: A Hyrax appliance modified as McNamara will be applied. SME group: A removable appliance with central expander will be applied. In order to evaluate the changes occurring, two CBCT radiography will be taken for every individual: first, before treatment, second, after three months of retention for RME group and one month of retention for SME group

Study Timeline

• Study Start: 2018-03-19
• Study First Submitted: 2018-09-10
• Study First Submitted QC: 2018-09-11
• Study First Posted: 2018-09-12
• Primary Completion: 2019-01-19
• Study Completion: 2019-06-15
• Status Verified: 2019-07
• Last Update Submitted: 2019-07-16
• Last Update Posted: 2019-07-18

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 34

Inclusion Criteria

• Bilateral skeletal maxillary deficiency (symmetrical) which will be clinically and radiographically diagnosed.
• Bilateral or unilateral functional posterior crossbite ( combined with mandibular shifting)
• Class I or II malocclusion.
• Normal or slight vertical growth pattern.

Exclusion Criteria

• Poor oral hygiene.
• Previous orthodontic treatment.
• Patients with syndromes, clefts, or craniofacial abnormalities.
• Patients with low facial height.
• A contraindication for rapid or slow maxillary expansion procedures.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Slow Maxillary Expansion	Slow Maxillary Expanding Device	Patients will undergo Slow Maxillary Expansion using a slow maxillary expanding device, i.e. a removable appliance with a central screw.
Rapid Maxillary Expansion	Rapid Maxillary Expanding Device	Patients will undergo Rapid Maxillary Expansion using a rapid maxillary expanding device, i.e. a Hyrax expander (modified by McNamra).

Primary Outcome Measures

Name	Time	Method
Change in the Pterygoid expansion width	T0: one day before the commencement of treatment; T1: after the end of active treatment and a retention period (which is expected within 14-15 weeks in the rapid expansion group and within 16-20 weeks in the slow expansion group)	This will be assessed using cone-beam computed tomography. The Pterygoid expansion width is measured between PtR and PtL on the images. (PtR. Pterygoideous right. The most caudal point of the apex of the right pterygoid process of the sphenoid. PtL. Pterygoideous left. Analogue to PtR, left side)
Change in molar tipping	T0: one day before the commencement of treatment; T1: after the end of active treatment and a retention period (which is expected within 14-15 weeks in the rapid expansion group and within 16-20 weeks in the slow expansion group)	This will be measured in cone-beam computed tomography images. Molar tipping is defined as the difference between (AR-AL) and (CR-CL) CR:Cuspid right which is the mesio-palatal cusp tip of the right maxillary first molar, whereas CL: Cuspid left which is the mesiopalatal cusp tip of the left maxillary first molar.; AR: Apex right which is the apex of the palatal root of the right maxillary first molar, where as AL: Apex left which is the apex of the palatal root of the left maxillary first molar.
Change in the mandibular path of closure	T0: one day before the commencement of treatment; T1: after the end of active treatment and a retention period (which is expected within 14-15 weeks in the rapid expansion group and within 16-20 weeks in the slow expansion group)	The path of the lower jaw from the rest position until closure will be clinically examined.; The path is classified as; 1. normal path of closure; 2. deviated path of closure due to premature contacts
Change in the anterior maxillary expansion width	T0: one day before the commencement of treatment; T1: after the end of active treatment and a retention period (which is expected within 14-15 weeks in the rapid expansion group and within 16-20 weeks in the slow expansion group)	This will be assessed using cone-beam computed tomography. The anterior maxillary expansion width is measured between RPyP-LPyP (RPyP: Right piriform point. The most lateral and caudal point of the nasal piriform aperture, at the boundary with the palatal cortex. LPyP: Analogue to RPyP, left side)
Change in the posterior expansion width	T0: one day before the commencement of treatment; T1: after the end of active treatment and a retention period (which is expected within 14-15 weeks in the rapid expansion group and within 16-20 weeks in the slow expansion group)	This will be assessed using cone-beam computed tomography. The posterior maxillary expansion width is measured between RPaFoP and LPaFoP (RPaFoP: Right palatine foramen point. The most posterior point of the right greater palatine foramen in the maxilla within the palatal cortex. LPaFoP: Analogue to RPaFOPr, left side.)
Change in the inter-molar width	T0: one day before the commencement of treatment; T1: after the end of active treatment and a retention period (which is expected within 14-15 weeks in the rapid expansion group and within 16-20 weeks in the slow expansion group)	This will be assessed using cone-beam computed tomography. The inter-molar width is measured at molar cusps between the right and left teeth.

Trial Locations

Locations (1)

Department of Orthodontics, University of Damascus Dental School; 🇸🇾 Damascus, Syrian Arab Republic