Dentoskeletal Effects of the Expander With Differential Opening and the Fan-type Expander

April 16, 2019 updated by: Camila Massaro, University of Sao Paulo

Maxillary Expander With Differential Opening Versus Fan-type Expander: a Randomized Clinical Trial

This study will assess the dentoskeletal effects of two types of maxillary expanders in orthodontic patients in the mixed dentition, from 7 to 11 years old. Half of participants will be treated using the expander with differential opening, while the other half will undergo rapid maxillary expansion using the fan-type expander. The null hypothesis is that there is no difference between dentoskeletal effects of the two protocols.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Rapid maxillary expansion (RME) is the orthopedic procedure of choice to treat maxillary constriction and posterior crossbite, and the study of dental, skeletal and periodontal effects of this procedure has been widely discussed in the orthodontic literature. The conventional RME expanders promote a similar expansion in the anterior and posterior regions of the maxillary arch. On the other hand, the fan-type expander allows the expansion concentrated in the intercanine region with little effects the intermolar distance. Finally, the expander with differential opening has two palatal screws and the differential activation protocol promotes a different amount of expansion for the anterior and posterior regions of the maxilla. No clinical study compared dental and skeletal effects of the expander with differential opening with those of the fan-type expander, including a three-dimensional analysis using CBCT exams and digital dental models. So, the aim of the present randomized clinical trial is to compare the skeletal and dentoalveolar effects of the maxillary expander with differential opening and the fan-type expander in the mixed dentition.

For this, patients will be recruited at the Orthodontic Clinic of Bauru Dental School, University of São Paulo, Brazil. A sample of 48 patients from 7 to 11 years old with transverse maxillary dental arch constriction will be prospectively and randomly allocated into two study groups. The first group will consist of 24 individuals treated with the expander with differential opening (DEG). The second group will consist of 24 individuals treated with the fan-type expander (FEG). In 12 patients from each group (immediate subgroups), a cone-beam computed tomography (CBCT) will be performed in the beginning of treatment (T1) and immediately after the rapid maxillary expansion (T2). In the other 24 patients, 12 from DEG and 12 from FEG (late subgroups), a CBCT will be obtained at T1 and 6 months after maxillary expansion (T3). Dental models will be obtained for all patients at T1 and T3. In digital dental models, maxillary arch width, perimeter, length and shape will be assessed. Standardized CBCT coronal sections will be used for measuring maxillary transverse dimensions, nasal cavity width and posterior tooth inclinations. Segmentation and superimposition of T1 and T3 CBCT images at the cranial base will be also performed. The opening of the midpalatal suture at the anterior and posterior region and the geometry of the suture opening will be evaluated in axial reconstructions of the CBCT.Discomfort, pain and quality of life will be evaluated by questionnaires.

After the normality test, the paired t test will be used in the intragroup comparison, and the independent t test will be used in the intergroup comparison. In the case of lost to follow-up patients, intention to treat analysis will be used. A significance level of 5% will be regarded for all tests.

Possible harms that could appear are related to temporary discomfort during the first days after the installation of the expander. Patients and legal guardians will be carefully oriented and they will be able to stop the treatment at any moment.

Study Type

Interventional

Enrollment (Actual)

48

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Brazil
    • São Paulo
      • Bauru, São Paulo, Brazil, 17012-901
        • Bauru Dental School - University of São Paulo

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

7 years to 11 years (Child)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Both sexes;
  • Mixed dentition;
  • Ages ranging from 7 to 11 years old;
  • Maxillary constriction associated to posterior crossbites;
  • Angle Class I or Angle Class II malocclusions.

Exclusion Criteria:

  • Cleft lip and palate;
  • Craniofacial syndromes;
  • Carious lesions;
  • Angle Class III malocclusion;
  • History of previous orthodontic treatment.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Differential Expansion Group
The experimental group will be comprised 24 patients treated with a rapid maxillary expansion using the expander with differential opening. The expander is composed by two screws, one posteriorly and the other anteriorly positioned on the palate.
Device: Differential Expansion
Twenty-four patients will be treated with a rapid maxillary expansion using the expander with differential opening. Appliance anchorage will be performed by bands adapted in the second maxillary deciduous molars and circumferential clamps will be bonded to the maxillary deciduous canines. The activation protocols will totalize an opening of 8mm in the anterior screw of the expander. After the active period of RME, the screws will be fixed with acrylic resin and the appliance will be kept as a retainer for 6 months.
Active Comparator: Fan-Fype Expander Group
The active comparator group will be comprised by 24 patients treated with rapid maxillary expansion using the the fan-type expander. The expander is composed by one screw anteriorly positioned on the palate.
Device: Fan-Fype Expander
Twenty-four patients will be treated with a rapid maxillary expansion using the fan-type expander. Appliance anchorage will be performed by bands adapted in the second maxillary deciduous molars and circumferential clamps will be bonded to the maxillary deciduous canines. The activation protocols will totalize an opening of 8mm screw of the expander. After the active period of RME, the screws will be fixed with acrylic resin and the appliance will be kept as a retainer for 6 months.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Maxillary and mandibular arch width (mm)
Time Frame: 6 months
Measurements will be performed in digital dental models
6 months
Maxillary and mandibular arch length
Time Frame: 6 months
Measurements will be performed in digital dental models
6 months
Maxillary and mandibular arch perimeter (mm)
Time Frame: 6 months
Measurements will be performed in digital dental models
6 months
Nasal cavity width (mm)
Time Frame: 6 months
Measurements will be performed in coronal sections of CBCT exams.
6 months
Maxillary width (mm)
Time Frame: 6 months
Measurements will be performed in coronal sections of CBCT exams.
6 months
Maxillary molars inclination (°)
Time Frame: 6 months
Measurement will be performed in CBCT scans.
6 months
Maxillary deciduous canines inclination (°)
Time Frame: 6 months
Measurement be performed CBCT scans.
6 months
Amount of interincisor diastema (mm)
Time Frame: 10 days
Measurement will be assessed in CBCT scans.
10 days
Opening of the midpalatal suture (mm)
Time Frame: 10 days
Measurement be assessed in axial and coronal sections of CBCT scans.
10 days

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Discomfort evaluation using questionnaires
Time Frame: 1 month
A Visual Analog Scale will be used from 0 to 10 cm.
1 month
Quality of life evaluation using questionnaires
Time Frame: 6 months
The Child Perceptions Questionnaire (CPQ8-10) will be used to evaluate the quality of life of the patients before and after treatment.
6 months
Dentoskeletal displacements by three-dimensional superimposition of CBCT scams.
Time Frame: 6 months
6 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of Sao Paulo

Collaborators

Fundação de Amparo à Pesquisa do Estado de São Paulo
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

November 8, 2017

Primary Completion (Actual)

December 15, 2018

Study Completion (Actual)

February 1, 2019

Study Registration Dates

First Submitted

October 7, 2018

First Submitted That Met QC Criteria

October 10, 2018

First Posted (Actual)

October 15, 2018

Study Record Updates

Last Update Posted (Actual)

April 18, 2019

Last Update Submitted That Met QC Criteria

April 16, 2019

Last Verified

April 1, 2019

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 71648917.6.0000.5417

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

No

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Malocclusion

Clinical Trials on Differential Expansion

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Mongolia

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

3
Subscribe