Maxillary Constriction in Growing ChildrenNCT07456917
Effects of BREA and MFT Expansion Appliances on Upper Airway Dimensions
A study testing Maxillary fixed three screw palatal expander (MFT) and Bimaxillary removable expansion appliance (BREA) in people with Maxillary Constriction in Growing Children and Transverse Maxillary Deficiency, run by Medical University of Silesia at 1 site in Poland.
Trial summary
This retrospective study evaluated whether orthodontic expansion using two types of appliances, a bimaxillary removable expansion appliance (BREA) and a maxillary fixed three screw palatal expander (MFT), influences upper airway dimensions, hyoid bone position, and palatal morphology in growing children. Read more about this study
- Who is it for?
- Ages 4 to 12 yearsHealthy volunteers can take part
- Conditions the study is for
- Maxillary Constriction in Growing Children, Transverse Maxillary Deficiency, Upper Airway Morphology in Children
- What is being tested?
- Maxillary fixed three screw palatal expander (MFT) and Bimaxillary removable expansion appliance (BREA)
- Type of treatment
- Pill or oral medicine, Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 79 participants
- Where
- 1 sitePoland
- Study dates
- 1 Feb 2020to 1 Feb 2026
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 4 to 12 years
- All sexes
- Healthy volunteers accepted
- Child
Who may be able to join
- Children aged 4 to 12 years at baseline. Patients in primary or mixed dentition stage.
- Availability of complete orthodontic diagnostic records at two time points, including:
- lateral cephalometric radiograph posteroanterior cephalometric radiograph dental models suitable for digital analysis For treated groups: orthodontic expansion performed with either BREA or MFT according to routine clinical indications.
- For control group: patients who underwent full orthodontic diagnostics but did not initiate orthodontic treatment during the observation period.
- Good general health without systemic conditions known to significantly affect craniofacial growth.
Who cannot join
- Presence of cleft lip and/or palate. Previous orthodontic treatment prior to baseline records. Presence of generalized spacing or diastema that could affect transverse measurements.
- Incomplete or missing radiographic records. Poor quality radiographs preventing reliable cephalometric analysis. Poor quality dental models, including artifacts on the palatal surface or indistinct gingival margins.
- Craniofacial syndromes or conditions known to significantly alter craniofacial development.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Effects of BREA and MFT Expansion Appliances on Upper Airway Dimensions, Hyoid Bone Position and Palatal Morphology in Growing Children
This retrospective study evaluated whether orthodontic expansion using two types of appliances, a bimaxillary removable expansion appliance (BREA) and a maxillary fixed three screw palatal expander (MFT), influences upper airway dimensions, hyoid bone position, and palatal morphology in growing children. Seventy nine children aged 4 to 12 years were included. Fifty five patients received orthodontic expansion (BREA or MFT), and twenty four untreated patients served as controls. Lateral and posteroanterior cephalometric radiographs and digital dental models obtained before and after the observation period were analyzed. Measurements assessed nasal and hypopharyngeal airway dimensions, the position of the hyoid bone, and transverse and volumetric characteristics of the palate. Compared with untreated children, those who underwent expansion showed significant increases in selected airway dimensions, widening of the upper piriform aperture, and increased distance between the hyoid bone and the mandibular symphysis. Both appliances increased maxillary transverse widths, with greater maxillary expansion observed in the MFT group. Palatal volume increased significantly with BREA, whereas palatal surface area increased and palatal depth decreased significantly with MFT. These findings suggest that orthodontic expansion in growing children may favorably modify selected upper airway and palatal parameters. Further prospective studies are needed to determine the long term functional and clinical significance of these changes.
Read the detailed description
This retrospective observational study was designed to evaluate dentofacial and upper airway changes associated with orthodontic expansion in growing children. The analysis focused on two expansion modalities: a bimaxillary removable expansion appliance (BREA) and a maxillary fixed three screw palatal expander (MFT). The primary objective was to determine whether these appliances influence piriform aperture width, hypopharyngeal dimensions, hyoid bone position, and palatal morphology during active craniofacial growth. The study included children aged 4 to 12 years who underwent comprehensive orthodontic diagnostics in a private orthodontic practice. Eligible patients had no history of cleft lip or palate, no previous orthodontic treatment, and no interdental spacing or diastema. The treated cohort comprised patients managed with either BREA or MFT according to clinical indications. A control cohort consisted of patients who completed full orthodontic diagnostics at two time points but did not initiate treatment. Ethical approval was obtained from the Bioethics Committee of the Medical University of Silesia. Standardized lateral and posteroanterior cephalometric radiographs were obtained in natural head position with controlled occlusion and breathing conditions. Digital dental models were generated from alginate impressions and intraoral scanning. Two dimensional airway and hyoid measurements were derived from calibrated cephalograms using dedicated cephalometric software. Three dimensional palatal surface area, volume, depth, and transverse interdental distances were calculated from digital models using certified orthodontic software. The primary analytical approach compared longitudinal changes between treated and untreated groups. Independent samples tests and analysis of covariance were applied to two dimensional variables, adjusting for sex and baseline age. One way analysis of variance with post hoc testing was used for three dimensional comparisons between appliance subgroups. Statistical significance was predefined at p less than 0.05. The study was exploratory in nature and aimed to characterize morphologic trends associated with early orthodontic expansion rather than to establish causal clinical outcomes. No therapeutic interventions beyond routine orthodontic care were introduced for research purposes. The results are intended to inform future prospective investigations evaluating functional respiratory and craniofacial implications of expansion therapy in pediatric populations.
- Conditions
- Maxillary Constriction in Growing Children, Transverse Maxillary Deficiency, Upper Airway Morphology in Children, Orthodontic Expansion Effects, Hyoid Bone Positional Changes
- Being tested
- Maxillary fixed three screw palatal expander (MFT), Bimaxillary removable expansion appliance (BREA)
- Keywords
- BREA, MFT expander, palatal expansion, maxillary expansion, upper airway
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Maxillary fixed three screw palatal expander (MFT)Device
Also called Three screw maxillary expander, MFT appliance, Hyrax type maxillary expander (modified)
A fixed orthodontic maxillary expansion device anchored to posterior teeth with acrylic splints and incorporating one central Hyrax type expansion screw and two auxiliary transverse screws. The central screw was activated once daily (up to 28 turns) and the lateral screws once every five days (up to 10 turns) according to the clinical protocol. The appliance was used in growing children to achieve transverse maxillary expansion. Treatment and imaging were part of routine orthodontic care.
Bimaxillary removable expansion appliance (BREA)Device
Also called BREA appliance, Removable bimaxillary expander, Two screw removable expander
A removable orthodontic appliance designed for simultaneous maxillary and mandibular transverse expansion. The device contains two expansion screws, one positioned in the maxillary arch and one in the mandibular arch. It was worn full time except during meals and oral hygiene. Both screws were activated once weekly in the horizontal plane according to the treatment protocol. The appliance was used in growing children as part of standard orthodontic management.
| Study group | Role | What they receive |
|---|---|---|
| MFT Expansion Group | Experimental | Participants received orthodontic treatment with a maxillary fixed three screw palatal expander (MFT) as part of routine clinical care. The appliance consisted of acrylic splints on the maxillary posterior teeth connected by a central Hyrax type screw and two auxiliary screws. The central screw was activated once daily and the lateral screws every five days according to the clinical protocol. Cephalometric radiographs and digital dental models obtained before and after treatment were analyzed to assess airway, hyoid, and palatal changes. Receives: Device: Maxillary fixed three screw palatal expander (MFT) |
| BREA Expansion Group | Experimental | Participants were treated with a removable bimaxillary expansion appliance (BREA) worn full time except during meals and oral hygiene. The device incorporated two expansion screws, one in the maxillary arch and one in the mandibular arch, both activated once weekly in the horizontal plane. Treatment followed routine orthodontic indications. Pre and post observation cephalometric radiographs and digital models were analyzed to evaluate changes in airway dimensions, hyoid position, and palatal morphology. Receives: Device: Bimaxillary removable expansion appliance (BREA) |
| Untreated Control Group | No intervention | Participants underwent standard orthodontic diagnostics at two time points but did not receive expansion therapy. These patients declined treatment and were followed observationally. Paired cephalometric radiographs and digital dental models were analyzed over the observation interval to provide a reference for natural growth related changes in airway parameters, hyoid position, and palatal morphology. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in upper airway and hyoid positional measurements on cephalometry
The primary outcome is the longitudinal change in selected upper airway and hyoid bone parameters measured on calibrated lateral and posteroanterior cephalometric radiographs. Key variables include piriform aperture width (NCULPA-NCURPA), hypopharyngeal airway dimension at C4ia (Z5-Z6), and the linear distance between the hyoid bone and mandibular symphysis (rGn-H). Values are calculated as the difference between post-treatment and baseline measurements and compared between study arms.
Measured: Baseline and post-treatment observation period (mean approximately 6 to 12 months, depending on individual treatment duration)
Secondary outcomes (2)
Changes in palatal morphology and transverse interdental dimensions
Secondary outcomes include three dimensional changes in palatal morphology and dental arch width derived from digital models. Assessed variables comprise palatal volume (PV), palatal surface area (PSA), palatal depth (PD1, PD2), palatal length (PL), and transverse interdental distances in the maxillary and mandibular arches (3+3, 4+4, 5+5, 6+6 and 3-3, 4-4, 5-5, 6-6). Measurements are calculated as post minus pre values normalized to the observation period and compared between study arms.
Measured: Baseline and post-treatment observation period (mean approximately 6 to 12 months, depending on individual treatment duration)
Change in piriform aperture transverse width
This secondary outcome evaluates the longitudinal change in the transverse dimension of the piriform aperture measured on calibrated posteroanterior cephalometric radiographs. The primary variable is NCULPA-NCURPA. Values are calculated as the difference between post-observation and baseline measurements and compared across study arms to assess the effect of orthodontic expansion on the bony nasal inlet.
Measured: Baseline and post-treatment observation period (mean approximately 6 to 12 months, depending on individual treatment duration)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Mar 2026
- Study start1 Feb 2020
- Primary completion1 Feb 2026
- Study completion1 Feb 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Maxillary Constriction in Growing ChildrenStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Model description
- Participants are allocated to one of three parallel groups according to clinical management: (1) treatment with a maxillary fixed three screw palatal expander (MFT), (2) treatment with a bimaxillary removable expansion appliance (BREA), or (3) untreated control with observational follow up. The study is retrospective and based on analysis of existing clinical records and imaging obtained at two time points. No randomization was performed, and group allocation reflected routine orthodontic decision making. Outcomes were compared longitudinally between groups.
- Masking
- None (open label)
- Enrolment
- 79 participants (actual)
Sponsor and investigators
- Lead sponsor
- Medical University of Silesia
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07456917
- Sponsor's protocol ID
- PCN/0022/KB1/11/21
- Status last verified
- Feb 2026
- First submitted
- 2 Mar 2026
- Last updated
- 9 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 9 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effects of BREA and MFT Expansion Appliances on Upper Airway Dimensions, Hyoid Bone Position and Palatal Morphology in Growing Children
- ClinicalTrials.gov ID
- NCT07456917
- Acronym / sponsor ID
- PCN/0022/KB1/11/21
- Conditions
- Maxillary Constriction in Growing Children, Transverse Maxillary Deficiency, Upper Airway Morphology in Children, Orthodontic Expansion Effects, Hyoid Bone Positional Changes
- Keywords
- BREA, MFT expander, palatal expansion, maxillary expansion, upper airway
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 79 participants (actual)
- Lead sponsor
- Medical University of SilesiaUniversity, hospital or other
- Study start
- 1 Feb 2020 (actual)
- Primary completion
- 1 Feb 2026 (actual)
- Study completion
- 1 Feb 2026 (actual)
- First posted
- 9 Mar 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This retrospective study evaluated whether orthodontic expansion using two types of appliances, a bimaxillary removable expansion appliance (BREA) and a maxillary fixed three screw palatal expander (MFT), influences upper airway dimensions, hyoid bone position, and palatal morphology in growing children. Seventy nine children aged 4 to 12 years were included. Fifty five patients received orthodontic expansion (BREA or MFT), and twenty four untreated patients served as controls. Lateral and posteroanterior cephalometric radiographs and digital dental models obtained before and after the observation period were analyzed. Measurements assessed nasal and hypopharyngeal airway dimensions, the position of the hyoid bone, and transverse and volumetric characteristics of the palate. Compared with untreated children, those who underwent expansion showed significant increases in selected airway dimensions, widening of the upper piriform aperture, and increased distance between the hyoid bone and the mandibular symphysis. Both appliances increased maxillary transverse widths, with greater maxillary expansion observed in the MFT group. Palatal volume increased significantly with BREA, whereas palatal surface area increased and palatal depth decreased significantly with MFT. These findings suggest that orthodontic expansion in growing children may favorably modify selected upper airway and palatal parameters. Further prospective studies are needed to determine the long term functional and clinical significance of these changes.
Detailed description
This retrospective observational study was designed to evaluate dentofacial and upper airway changes associated with orthodontic expansion in growing children. The analysis focused on two expansion modalities: a bimaxillary removable expansion appliance (BREA) and a maxillary fixed three screw palatal expander (MFT). The primary objective was to determine whether these appliances influence piriform aperture width, hypopharyngeal dimensions, hyoid bone position, and palatal morphology during active craniofacial growth. The study included children aged 4 to 12 years who underwent comprehensive orthodontic diagnostics in a private orthodontic practice. Eligible patients had no history of cleft lip or palate, no previous orthodontic treatment, and no interdental spacing or diastema. The treated cohort comprised patients managed with either BREA or MFT according to clinical indications. A control cohort consisted of patients who completed full orthodontic diagnostics at two time points but did not initiate treatment. Ethical approval was obtained from the Bioethics Committee of the Medical University of Silesia. Standardized lateral and posteroanterior cephalometric radiographs were obtained in natural head position with controlled occlusion and breathing conditions. Digital dental models were generated from alginate impressions and intraoral scanning. Two dimensional airway and hyoid measurements were derived from calibrated cephalograms using dedicated cephalometric software. Three dimensional palatal surface area, volume, depth, and transverse interdental distances were calculated from digital models using certified orthodontic software. The primary analytical approach compared longitudinal changes between treated and untreated groups. Independent samples tests and analysis of covariance were applied to two dimensional variables, adjusting for sex and baseline age. One way analysis of variance with post hoc testing was used for three dimensional comparisons between appliance subgroups. Statistical significance was predefined at p less than 0.05. The study was exploratory in nature and aimed to characterize morphologic trends associated with early orthodontic expansion rather than to establish causal clinical outcomes. No therapeutic interventions beyond routine orthodontic care were introduced for research purposes. The results are intended to inform future prospective investigations evaluating functional respiratory and craniofacial implications of expansion therapy in pediatric populations.
Study design
- Primary purpose
- Other
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 3
- Model description
- Participants are allocated to one of three parallel groups according to clinical management: (1) treatment with a maxillary fixed three screw palatal expander (MFT), (2) treatment with a bimaxillary removable expansion appliance (BREA), or (3) untreated control with observational follow up. The study is retrospective and based on analysis of existing clinical records and imaging obtained at two time points. No randomization was performed, and group allocation reflected routine orthodontic decision making. Outcomes were compared longitudinally between groups.
| Arm | Type | Receives |
|---|---|---|
| MFT Expansion Group | Experimental | Device: Maxillary fixed three screw palatal expander (MFT)Participants received orthodontic treatment with a maxillary fixed three screw palatal expander (MFT) as part of routine clinical care. The appliance consisted of acrylic splints on the maxillary posterior teeth connected by a central Hyrax type screw and two auxiliary screws. The central screw was activated once daily and the lateral screws every five days according to the clinical protocol. Cephalometric radiographs and digital dental models obtained before and after treatment were analyzed to assess airway, hyoid, and palatal changes. |
| BREA Expansion Group | Experimental | Device: Bimaxillary removable expansion appliance (BREA)Participants were treated with a removable bimaxillary expansion appliance (BREA) worn full time except during meals and oral hygiene. The device incorporated two expansion screws, one in the maxillary arch and one in the mandibular arch, both activated once weekly in the horizontal plane. Treatment followed routine orthodontic indications. Pre and post observation cephalometric radiographs and digital models were analyzed to evaluate changes in airway dimensions, hyoid position, and palatal morphology. |
| Untreated Control Group | No intervention | –Participants underwent standard orthodontic diagnostics at two time points but did not receive expansion therapy. These patients declined treatment and were followed observationally. Paired cephalometric radiographs and digital dental models were analyzed over the observation interval to provide a reference for natural growth related changes in airway parameters, hyoid position, and palatal morphology. |
Who may qualify
- Ages
- 4 to 12 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child
Key inclusion criteria (5 listed)
- Children aged 4 to 12 years at baseline. Patients in primary or mixed dentition stage.
- lateral cephalometric radiograph posteroanterior cephalometric radiograph dental models suitable for digital analysis For treated groups: orthodontic expansion performed with either BREA or MFT according to routine clinical indications.
- For control group: patients who underwent full orthodontic diagnostics but did not initiate orthodontic treatment during the observation period.
- Good general health without systemic conditions known to significantly affect craniofacial growth.
Key exclusion criteria (3 listed)
- Presence of cleft lip and/or palate. Previous orthodontic treatment prior to baseline records. Presence of generalized spacing or diastema that could affect transverse measurements.
- Incomplete or missing radiographic records. Poor quality radiographs preventing reliable cephalometric analysis. Poor quality dental models, including artifacts on the palatal surface or indistinct gingival margins.
- Craniofacial syndromes or conditions known to significantly alter craniofacial development.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Maxillary fixed three screw palatal expander (MFT)Also: Three screw maxillary expander, MFT appliance, Hyrax type maxillary expander (modified)A fixed orthodontic maxillary expansion device anchored to posterior teeth with acrylic splints and incorporating one central Hyrax type expansion screw and two auxiliary transverse screws. The central screw was activated once daily (up to 28 turns) and the lateral screws once every five days (up to 10 turns) according to the clinical protocol. The appliance was used in growing children to achieve transverse maxillary expansion. Treatment and imaging were part of routine orthodontic care. | Device | MFT Expansion Group |
| Bimaxillary removable expansion appliance (BREA)Also: BREA appliance, Removable bimaxillary expander, Two screw removable expanderA removable orthodontic appliance designed for simultaneous maxillary and mandibular transverse expansion. The device contains two expansion screws, one positioned in the maxillary arch and one in the mandibular arch. It was worn full time except during meals and oral hygiene. Both screws were activated once weekly in the horizontal plane according to the treatment protocol. The appliance was used in growing children as part of standard orthodontic management. | Device | BREA Expansion Group |
Primary outcome
Change in upper airway and hyoid positional measurements on cephalometry
Time frame: Baseline and post-treatment observation period (mean approximately 6 to 12 months, depending on individual treatment duration)
The primary outcome is the longitudinal change in selected upper airway and hyoid bone parameters measured on calibrated lateral and posteroanterior cephalometric radiographs. Key variables include piriform aperture width (NCULPA-NCURPA), hypopharyngeal airway dimension at C4ia (Z5-Z6), and the linear distance between the hyoid bone and mandibular symphysis (rGn-H). Values are calculated as the difference between post-treatment and baseline measurements and compared between study arms.
2 secondary outcomes
Changes in palatal morphology and transverse interdental dimensions
Time frame: Baseline and post-treatment observation period (mean approximately 6 to 12 months, depending on individual treatment duration)
Change in piriform aperture transverse width
Time frame: Baseline and post-treatment observation period (mean approximately 6 to 12 months, depending on individual treatment duration)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Mar 2026.
- Individual participant dataSharing planned: Undecided
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Maxillary fixed three screw palatal expander (MFT) and Bimaxillary removable expansion appliance (BREA) in people with Maxillary Constriction in Growing Children and Transverse Maxillary Deficiency, run by Medical University of Silesia at 1 site in Poland.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 9 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Poland. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in upper airway and hyoid positional measurements on cephalometry (time frame: Baseline and post-treatment observation period (mean approximately 6 to 12 months, depending on individual treatment duration)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Mar 2026.