Crowding of Anterior Maxillary TeethNCT06187337
Interceptive Maxillary Expansion to Relief Anterior Crowding in the Mixed Dentition
A study testing Maxillary expansion device in people with Crowding of Anterior Maxillary Teeth and Orthodontics, Interceptive, run by Region Örebro County at 4 sites in 2 countries.
Trial summary
The goal of this clinical trial is to compare if it is better to treat severe anterior crowding in the early mixed dentition then later in the permanent dentition in children with anterior crowding of the upper teeth. Read more about this study
- Who is it for?
- Ages 6 to 16 years
- Conditions the study is for
- Crowding of Anterior Maxillary Teeth, Orthodontics, Interceptive, Orthodontics, Corrective, Palatal Expansion Technique
- What is being tested?
- Maxillary expansion device
- Type of treatment
- Pill or oral medicine, Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- 4 sitesin 2 countries
- Study dates
- 20 Dec 2021to 31 Jan 2028
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
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 6 to 16 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Healthy subjects without sucking habits
- Permanent maxillary central incisors and first permanent molars fully erupted. DS1M1.
- No severe crowding or protrusion in the lower arch considering the Leeway space and normal development of the arch.
- Permanent first molar in normal transversal relation.
- Crowding of the maxillary incisors with the lateral incisor just erupting ectopically or not yet emerged through the gingiva.
- Crowding greater than or equal to 6 millimeters between the upper deciduous canines.
Who cannot join
- Skeletal asymmetries, anomalies and syndromes.
- Previous orthodontic treatment
Trial locations and contacts
4 sites in 2 countries. Contact the study team or a site near you to ask about taking part.
4 sites in 2 countries
Italy2 sites, 2 recruiting
- Recruiting
Postgraduate School of Orthodontics, University of L'Aquila
Coppito
Simone Ettore Salvati, DDS, simoneettore.salvati@graduate.univaq.it
- Recruiting
Universita Degli Studi Di Milano
Milan, 20122
Alberto Caprioglio, Professor, +39-02 50320240, alberto.caprioglio@unimi.it
Sweden2 sites, 2 recruiting
- Recruiting
The Institute for Postgraduate Dental Education in Jönköping
Jönköping
Cecilia Hedmo, DDS, cecilia.hedmo@rjl.se
- Recruiting
Emil Östlund
Örebro, 70383
Emil Östlund, +46196024045, emil.ostlund@regionorebrolan.se
About this study
Official title: Interceptive Maxillary Expansion to Relief Anterior Crowding in the Mixed Dentition: a Longitudinal, Randomized Controlled Trial
The goal of this clinical trial is to compare if it is better to treat severe anterior crowding in the early mixed dentition then later in the permanent dentition in children with anterior crowding of the upper teeth. The main questions this trial aims to answer are:
- If there is a difference in the degree of anterior crowding between the experimental group and the control group after a five year follow-up period.
- If there is a difference between the experimental group and the control group in regard to oral health related quality of life.
- If there is spontaneous transversal adaption of the lower dental arch to upper dental arch after maxillary expansion and compare this to the control group.
- If early maxillary expansion is more cost-effective than treatment in the permanent dentition.
Read more
To be eligible for this trial the subject must be children between six and nine years old at the time for inclusion. The children must have crowding of the upper front teeth of six millimeters or more and the lateral incisors should not have erupted or just erupted through the gingiva.
Subjects randomized to the experimental group will get an expansion treatment in the upper jaw with rapid maxillary expansion device to gain enough space for the lateral incisors to erupt. All subjects, also the subjects randomized to the control group, are followed until all permanent teeth have erupted.
At the end of the follow-up period all subjects fill out a questionnaire to evaluate their oral health related quality of life.
Researchers will then compare the subjects in both groups to evaluate if there is a difference in anterior crowding after the follow-up period. Differences in cost-effectiveness, morphological changes and the subjects oral health related quality of life will also be evaluated.
Read the detailed description
The study will be conducted on consecutively included subjects referred to the centers and then randomized into either an experimental group or a control group.
To be able to evaluate the amount of anterior crowding before the lateral incisors have erupted, low-dose Cone Beam Computed Tomography-scans are used to measure the width of the unerupted laterals. The anterior crowding is calculated by comparing the width of the laterals with measurements of the distance between the mesial surfaces of the deciduous upper canines on study casts. The eligible subjects are then randomized to either experimental och control group.
The subjects in the experimental group will be treated with a maxillary expansion appliance with bands on the second deciduous molars and arms to the deciduous canines. A small preparation on the palatal surface of the deciduous canines is performed to facilitate bonding of the arms. The screw gives a expansion of 0,20 millimeter per activation. The arms are bonded to the deciduous canines with light curing composite and the bands are cemented on the etched second deciduous molar with glassionomer cement.
Then the subject and the parents are instructed to activate the appliance once a day (1/4 turn) for 2 weeks and thereafter every second day until adequate space for the lateral incisors is obtained and the first permanent molars are approaching scissor-bite.
The expansion can be paused for 7-8 months after 25-30 activations if the lateral incisors are not yet erupted and the permanent molars are going in scissor-bite to allow for their spontaneous correction. The expansion is then continued until adequate space for the lateral permanent incisors is achieved.
During the expansion the subjects will be asked to complete a questionnaire on pain and discomfort.
When enough space is available for the crowding to be resolved the expander is blocked with light curing composite or a stainless steel ligature wire. The appliances is kept as a retainer until the laterals are fully erupted.
After the follow-up period the treatment effects will be evaluated by measuring of the study models. All measurements will be made digitally with the 3Shape OrthoAnalyzer Differences in palatal volume, transversal width of the maxillary and mandibular dentition between the start of the trial and at the end of the follow-up period will be measured. The questionnaires regarding pain and discomfort and PIDAQ will be analyzed.
The last part of the study is to perform a cost-effectiveness analysis for early treatment with maxillary expansion and a cost-effectiveness analysis for treatment in the permanent dentition and then compare them. The direct cost for both experiment and control group will be calculated by adding up material cost and chair-time cost. The indirect cost is defined as the cost for the parents regarding loss of income for the duration of the visits and the trips to and from the clinic. Due to the fact that there are substantial differences in traveling time and income for parents, the indirect costs of treatment will not be taken into account because the randomization will equalize the effect of the differences.
- Conditions
- Crowding of Anterior Maxillary Teeth, Orthodontics, Interceptive, Orthodontics, Corrective, Palatal Expansion Technique
- Being tested
- Maxillary expansion device
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Maxillary expansion deviceDevice
The maxillary expansion device is a orthodontic appliance that is used to expand the maxilla in children.
| Study group | Role | What they receive |
|---|---|---|
| Early maxillary expansion | Experimental | The subjects in the experimental group will be treated with a maxillary expansion appliance with bands on the second deciduous molars and arms to the deciduous canines. The screw gives a expansion of 0,20 millimeter per activation. The arms are bonded to the deciduous canines with light curing composite and the bands are cemented with glassionomer cement.
The subject are instructed to activate the appliance once a day (1/4 turn) for 2 weeks and thereafter every second day until adequate space for the lateral incisors is obtained.During the expansion the subjects will be asked to complete a questionnaire on pain and discomfort.
The subjects will be recalled for follow-up visits after 24 months (T1), 36 months (T2), 48 months (T3) and when all permanent premolars are erupted (T4).
At T1, T2 and T4 the subjects are asked to fill out the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ).
The subjects need for further treatment will be evaluated and initiated at T4. Receives: Device: Maxillary expansion device |
| Control group | No intervention | The control group is not going to receive any treatment under the observation period. The subjects will be recalled for follow-up visits with photographs (4 extraoral photos and 5 intraoral photos) and study models (digital or cast) after 24 months (T1), 36 months (T2), 48 months (T3) and when all permanent premolars are erupted (T4). At T1, T2 and T4 the subjects are asked to fill out the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) to evaluate their oral health related quality of life. The subjects need for further treatment will be evaluated and initiated at T4. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Long-term spontaneous alignment of anterior maxillary teeth
The long-term spontaneous alignment of anterior maxillary teeth will be evaluated visually and measure on the digital study models.
Measured: At the end of the observation period, an average of 5 years
Secondary outcomes (4)
Impact on oral health related quality of life
The impact of early expansion treatment on the oral health will be measure at the end of the observation period in both the experimental group and the control group. This will be measured with the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ). The PIDAQ is made of four subparts;
- Dental Self-Confidence; six questions answered on a Likert-scale between 0 and 4. Maximum score is 24 och minimum is zero. Higher score is better.
- Social Impact: eight questions answered on a Likert-scale between 0 and 4. Maximum score is 32 and zero minimum. Lower score is better.
- Psychological Impact: six questions answered on a Likert-scale between 0 and 4. Maximum score is 24 and zero minimum. Lower score is better.
- Aestethic Concern: three questions answered on a Likert-scale between 0 and 4. Maximum score is twelve and zero minimum. Lower score is better
Measured: At the end of the observation period, an average of 5 years.
Cost-effectiveness of early expansion treatment
The total cost of treatments in both the control- and experimental group will be compared to evaluate which treatment is the most cost-effective.
Measured: At the end of the observation period, an average of 5 years.
Morphological changes in the upper and lower arches.
The morphological changes after expansion will be measured on study models and compared to the study models at the start point. The same will be conducted on the study models for the control group.
Measured: At the end of the observation period, an average of 5 years.
Complications of expansion.
This measure will be reported descriptive and the complications analyzed.
Measured: At the end of the observation period, an average of 5 years.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Jan 2024
- Study start20 Dec 2021
- Primary completion31 Jan 2027 (estimated)
- Study completion31 Jan 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Crowding of Anterior Maxillary TeethStudies 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
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- This is a 2-arm parallel-group, randomized controlled trial with a 1:1 allocation ratio.
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Region Örebro County
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06187337
- Sponsor's protocol ID
- 275470
- Status last verified
- May 2025
- First submitted
- 17 Nov 2023
- Last updated
- 18 Jul 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 18 Jul 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Interceptive Maxillary Expansion to Relief Anterior Crowding in the Mixed Dentition: a Longitudinal, Randomized Controlled Trial
- ClinicalTrials.gov ID
- NCT06187337
- Acronym / sponsor ID
- 275470
- Conditions
- Crowding of Anterior Maxillary Teeth, Orthodontics, Interceptive, Orthodontics, Corrective, Palatal Expansion Technique
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 60 participants (estimated)
- Lead sponsor
- Region Örebro CountyUniversity, hospital or other
- Study start
- 20 Dec 2021 (actual)
- Primary completion
- 31 Jan 2027 (estimated)
- Study completion
- 31 Jan 2028 (estimated)
- First posted
- 2 Jan 2024 (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.
The goal of this clinical trial is to compare if it is better to treat severe anterior crowding in the early mixed dentition then later in the permanent dentition in children with anterior crowding of the upper teeth. The main questions this trial aims to answer are:
- If there is a difference in the degree of anterior crowding between the experimental group and the control group after a five year follow-up period.
- If there is a difference between the experimental group and the control group in regard to oral health related quality of life.
- If there is spontaneous transversal adaption of the lower dental arch to upper dental arch after maxillary expansion and compare this to the control group.
- If early maxillary expansion is more cost-effective than treatment in the permanent dentition.
To be eligible for this trial the subject must be children between six and nine years old at the time for inclusion. The children must have crowding of the upper front teeth of six millimeters or more and the lateral incisors should not have erupted or just erupted through the gingiva.
Subjects randomized to the experimental group will get an expansion treatment in the upper jaw with rapid maxillary expansion device to gain enough space for the lateral incisors to erupt. All subjects, also the subjects randomized to the control group, are followed until all permanent teeth have erupted.
At the end of the follow-up period all subjects fill out a questionnaire to evaluate their oral health related quality of life.
Researchers will then compare the subjects in both groups to evaluate if there is a difference in anterior crowding after the follow-up period. Differences in cost-effectiveness, morphological changes and the subjects oral health related quality of life will also be evaluated.
Detailed description
The study will be conducted on consecutively included subjects referred to the centers and then randomized into either an experimental group or a control group.
To be able to evaluate the amount of anterior crowding before the lateral incisors have erupted, low-dose Cone Beam Computed Tomography-scans are used to measure the width of the unerupted laterals. The anterior crowding is calculated by comparing the width of the laterals with measurements of the distance between the mesial surfaces of the deciduous upper canines on study casts. The eligible subjects are then randomized to either experimental och control group.
The subjects in the experimental group will be treated with a maxillary expansion appliance with bands on the second deciduous molars and arms to the deciduous canines. A small preparation on the palatal surface of the deciduous canines is performed to facilitate bonding of the arms. The screw gives a expansion of 0,20 millimeter per activation. The arms are bonded to the deciduous canines with light curing composite and the bands are cemented on the etched second deciduous molar with glassionomer cement.
Then the subject and the parents are instructed to activate the appliance once a day (1/4 turn) for 2 weeks and thereafter every second day until adequate space for the lateral incisors is obtained and the first permanent molars are approaching scissor-bite.
The expansion can be paused for 7-8 months after 25-30 activations if the lateral incisors are not yet erupted and the permanent molars are going in scissor-bite to allow for their spontaneous correction. The expansion is then continued until adequate space for the lateral permanent incisors is achieved.
During the expansion the subjects will be asked to complete a questionnaire on pain and discomfort.
When enough space is available for the crowding to be resolved the expander is blocked with light curing composite or a stainless steel ligature wire. The appliances is kept as a retainer until the laterals are fully erupted.
After the follow-up period the treatment effects will be evaluated by measuring of the study models. All measurements will be made digitally with the 3Shape OrthoAnalyzer Differences in palatal volume, transversal width of the maxillary and mandibular dentition between the start of the trial and at the end of the follow-up period will be measured. The questionnaires regarding pain and discomfort and PIDAQ will be analyzed.
The last part of the study is to perform a cost-effectiveness analysis for early treatment with maxillary expansion and a cost-effectiveness analysis for treatment in the permanent dentition and then compare them. The direct cost for both experiment and control group will be calculated by adding up material cost and chair-time cost. The indirect cost is defined as the cost for the parents regarding loss of income for the duration of the visits and the trips to and from the clinic. Due to the fact that there are substantial differences in traveling time and income for parents, the indirect costs of treatment will not be taken into account because the randomization will equalize the effect of the differences.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
- Model description
- This is a 2-arm parallel-group, randomized controlled trial with a 1:1 allocation ratio.
| Arm | Type | Receives |
|---|---|---|
| Early maxillary expansion | Experimental | Device: Maxillary expansion deviceThe subjects in the experimental group will be treated with a maxillary expansion appliance with bands on the second deciduous molars and arms to the deciduous canines. The screw gives a expansion of 0,20 millimeter per activation. The arms are bonded to the deciduous canines with light curing composite and the bands are cemented with glassionomer cement. The subject are instructed to activate the appliance once a day (1/4 turn) for 2 weeks and thereafter every second day until adequate space for the lateral incisors is obtained.During the expansion the subjects will be asked to complete a questionnaire on pain and discomfort. The subjects will be recalled for follow-up visits after 24 months (T1), 36 months (T2), 48 months (T3) and when all permanent premolars are erupted (T4). At T1, T2 and T4 the subjects are asked to fill out the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ). The subjects need for further treatment will be evaluated and initiated at T4. |
| Control group | No intervention | –The control group is not going to receive any treatment under the observation period. The subjects will be recalled for follow-up visits with photographs (4 extraoral photos and 5 intraoral photos) and study models (digital or cast) after 24 months (T1), 36 months (T2), 48 months (T3) and when all permanent premolars are erupted (T4). At T1, T2 and T4 the subjects are asked to fill out the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) to evaluate their oral health related quality of life. The subjects need for further treatment will be evaluated and initiated at T4. |
Who may qualify
- Ages
- 6 to 16 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (6 listed)
- Healthy subjects without sucking habits
- Permanent maxillary central incisors and first permanent molars fully erupted. DS1M1.
- No severe crowding or protrusion in the lower arch considering the Leeway space and normal development of the arch.
- Permanent first molar in normal transversal relation.
- Crowding of the maxillary incisors with the lateral incisor just erupting ectopically or not yet emerged through the gingiva.
Key exclusion criteria (2 listed)
- Skeletal asymmetries, anomalies and syndromes.
- Previous orthodontic treatment
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 expansion deviceThe maxillary expansion device is a orthodontic appliance that is used to expand the maxilla in children. | Device | Early maxillary expansion |
Primary outcome
Long-term spontaneous alignment of anterior maxillary teeth
Time frame: At the end of the observation period, an average of 5 years
The long-term spontaneous alignment of anterior maxillary teeth will be evaluated visually and measure on the digital study models.
4 secondary outcomes
Impact on oral health related quality of life
Time frame: At the end of the observation period, an average of 5 years.
Cost-effectiveness of early expansion treatment
Time frame: At the end of the observation period, an average of 5 years.
Morphological changes in the upper and lower arches.
Time frame: At the end of the observation period, an average of 5 years.
Complications of expansion.
Time frame: At the end of the observation period, an average of 5 years.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Jul 2025.
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.
4 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Maxillary expansion device in people with Crowding of Anterior Maxillary Teeth and Orthodontics, Interceptive, run by Region Örebro County at 4 sites in 2 countries.
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 6 inclusion and 2 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: looking for participants now, as of the sponsor's last update on 18 Jul 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 4 sites in Italy, Sweden. 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?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Emil Östlund, DDS (+46196024045, emil.ostlund@regionorebrolan.se), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Long-term spontaneous alignment of anterior maxillary teeth (time frame: At the end of the observation period, an average of 5 years). 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 18 Jul 2025.