Skeletal Class III MalocclusionNCT07433842
Surgery-First Orthognathic Surgery in Skeletal Class III Treatment
A study testing Surgery-First Orthognathic Surgery in people with Skeletal Class III Malocclusion, run by Hanoi Medical University at 1 site in Vietnam.
Trial summary
This study evaluates the efficacy and stability of the "Surgery-First" approach (SF approach) in treating patients with skeletal Class III malocclusion, utilizing a combined retrospective and prospective data collection method. Read more about this study
- Who is it for?
- Ages 16 years and older
- Conditions the study is for
- Skeletal Class III Malocclusion
- What is being tested?
- Surgery-First Orthognathic Surgery
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- 1 siteVietnam
- Study dates
- 1 Mar 2022to 1 May 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 16 years and older
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Who may be able to join
- Female patients aged 16 years or older, and male patients aged 18 years or older.
- Diagnosis of skeletal Class III malocclusion.
- Meeting the clinical indications for the Surgery-First orthognathic approach.
- Treatment plan consensus between the orthodontist and maxillofacial surgeon, aligned with the patient's chief complaint and expectations.
- Underwent orthognathic surgery using the Surgery-First approach without pre-surgical orthodontic treatment.
- Good general health, fit for general anesthesia.
- Voluntarily agreed to participate in the study and provided informed consent.
Who cannot join
- Dentofacial deformities secondary to maxillofacial trauma (e.g., midface retrusion due to Le Fort fractures, or mandibular retrusion due to bilateral condylar fractures).
- Presence of systemic diseases or conditions that contraindicate general anesthesia or orthognathic surgery.
- Presence of psychiatric disorders that may compromise treatment cooperation or the informed consent process.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Surgery First Orthognathic Surgery in Skeletal Class III Treatment: A Study on Digital Dental Models and Computed Tomography Changes
This study evaluates the efficacy and stability of the "Surgery-First" approach (SF approach) in treating patients with skeletal Class III malocclusion, utilizing a combined retrospective and prospective data collection method. Unlike the conventional method, the SF approach performs orthognathic surgery first to correct the skeletal discrepancy, followed by orthodontic treatment. The study aims to analyze pre-operative dentoskeletal characteristics, arch morphology, and treatment complexity indices, as well as assess the hard and soft tissue changes at 1 week and 1 year post-surgery using digital dental models and Computed Tomography (CT) scans.
Read the detailed description
This is a single-arm interventional study designed to evaluate the efficacy and stability of the Surgery-First approach in patients with skeletal Class III malocclusion. The study utilizes a combined retrospective and prospective data collection method.
The study protocol was approved by the Institutional Ethics Committee in October 2022. The study population includes patients diagnosed with skeletal Class III malocclusion who underwent the Surgery-First orthognathic surgery between June 2019 and March 2025.
Study Procedures:
Baseline Assessment (T0): Pre-operative evaluation includes clinical examination, digital dental model analysis (to assess occlusal characteristics, arch morphology, and treatment need/complexity indices such as ICON and IOFTN), and Computed Tomography (CT) scanning to measure hard and soft tissue characteristics.
Surgical Intervention: All patients underwent the surgery-first orthognathic approach without pre-surgical orthodontic preparation. A CT scan was performed 1 week post-surgery (T1) to evaluate the immediate surgical results.
Follow-up (T2): Post-operative assessment and CT scanning are conducted 12 months post-surgery (T2) to evaluate skeletal stability and soft tissue adaptation.
Data Analysis:
The analysis focuses on the pre-surgical dentoskeletal characteristics and treatment need indices at baseline, as well as the displacement of the maxilla/mandible and soft tissue changes between time points (T0, T1, and T2).
- Conditions
- Skeletal Class III Malocclusion
- Being tested
- Surgery-First Orthognathic Surgery
- Keywords
- surgery first orthognathic approach, digital dental model, computed tomography, 3D analysis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Surgery-First Orthognathic SurgeryProcedure or surgery
Orthognathic surgery (Le Fort I, BSSO, or double jaw surgery) performed before orthodontic treatment to correct skeletal discrepancy.
| Study group | Role | What they receive |
|---|---|---|
| Surgery-First Cohort | Experimental | Patients diagnosed with skeletal Class III malocclusion who undergo the Surgery-First approach. Receives: Procedure: Surgery-First Orthognathic Surgery |
What is being measured
The primary outcome is the main question the study is designed to answer.
Three-Dimensional Skeletal and Soft Tissue Changes on Computed Tomography (CT)
Evaluation of dentoskeletal and facial soft tissue changes. The measurements include the three-dimensional (3D) spatial displacement of hard and soft tissue landmarks, as well as angular and linear cephalometric parameters (e.g., SNA, SNB, ANB angles) measured on Computed Tomography (CT) images. Comparisons are made across three time points to assess immediate surgical changes and long-term stability.
Measured: Baseline (T0), 1 week post-surgery (T1), and 12 months post-surgery (T2)
Secondary outcomes (1)
Pre-surgical Dental Arch Characteristics and Treatment Need Indices
Assessment of pre-surgical occlusal characteristics and arch morphology using 3D digital dental models. The evaluated parameters include, but are not limited to, overbite, overjet, Arch Length Discrepancy (ALD), Intercanine Width (ICW) and Intermolar Width (IMW) discrepancies, Arch Form Asymmetry Index (AI), Asymmetric Tooth Number (ATN), and the depth of the Curve of Spee. Additionally, the complexity and functional need for treatment are evaluated using standardized indices such as the Index of Complexity, Outcome and Need (ICON) and the Index of Orthognathic Functional Treatment Need (IOFTN).
Measured: Baseline (T0)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Feb 2026
- Study start1 Mar 2022
- Primary completion1 Apr 2026
- Study completion1 May 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Skeletal Class III MalocclusionStudies 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
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 60 participants (actual)
Sponsor and investigators
- Lead sponsor
- Hanoi Medical University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Nguyen Truong Minh, Hanoi Medical University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07433842
- Sponsor's protocol ID
- 657/GCN-HDDDNCYSH-DHYHN
- Status last verified
- May 2026
- First submitted
- 19 Feb 2026
- Last updated
- 19 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: There is no plan to share individual participant data to protect patient privacy and intellectual property before all publications are completed.
Study at a glance
From the registry record, last updated by the sponsor on 19 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Surgery First Orthognathic Surgery in Skeletal Class III Treatment: A Study on Digital Dental Models and Computed Tomography Changes
- ClinicalTrials.gov ID
- NCT07433842
- Acronym / sponsor ID
- 657/GCN-HDDDNCYSH-DHYHN
- Conditions
- Skeletal Class III Malocclusion
- Keywords
- surgery first orthognathic approach, digital dental model, computed tomography, 3D analysis
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 60 participants (actual)
- Lead sponsor
- Hanoi Medical UniversityUniversity, hospital or other
- Study start
- 1 Mar 2022 (actual)
- Primary completion
- 1 Apr 2026 (actual)
- Study completion
- 1 May 2026 (actual)
- First posted
- 25 Feb 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 study evaluates the efficacy and stability of the "Surgery-First" approach (SF approach) in treating patients with skeletal Class III malocclusion, utilizing a combined retrospective and prospective data collection method. Unlike the conventional method, the SF approach performs orthognathic surgery first to correct the skeletal discrepancy, followed by orthodontic treatment. The study aims to analyze pre-operative dentoskeletal characteristics, arch morphology, and treatment complexity indices, as well as assess the hard and soft tissue changes at 1 week and 1 year post-surgery using digital dental models and Computed Tomography (CT) scans.
Detailed description
This is a single-arm interventional study designed to evaluate the efficacy and stability of the Surgery-First approach in patients with skeletal Class III malocclusion. The study utilizes a combined retrospective and prospective data collection method.
The study protocol was approved by the Institutional Ethics Committee in October 2022. The study population includes patients diagnosed with skeletal Class III malocclusion who underwent the Surgery-First orthognathic surgery between June 2019 and March 2025.
Study Procedures:
Baseline Assessment (T0): Pre-operative evaluation includes clinical examination, digital dental model analysis (to assess occlusal characteristics, arch morphology, and treatment need/complexity indices such as ICON and IOFTN), and Computed Tomography (CT) scanning to measure hard and soft tissue characteristics.
Surgical Intervention: All patients underwent the surgery-first orthognathic approach without pre-surgical orthodontic preparation. A CT scan was performed 1 week post-surgery (T1) to evaluate the immediate surgical results.
Follow-up (T2): Post-operative assessment and CT scanning are conducted 12 months post-surgery (T2) to evaluate skeletal stability and soft tissue adaptation.
Data Analysis:
The analysis focuses on the pre-surgical dentoskeletal characteristics and treatment need indices at baseline, as well as the displacement of the maxilla/mandible and soft tissue changes between time points (T0, T1, and T2).
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Surgery-First Cohort | Experimental | Procedure: Surgery-First Orthognathic SurgeryPatients diagnosed with skeletal Class III malocclusion who undergo the Surgery-First approach. |
Who may qualify
- Ages
- 16 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (7 listed)
- Female patients aged 16 years or older, and male patients aged 18 years or older.
- Diagnosis of skeletal Class III malocclusion.
- Meeting the clinical indications for the Surgery-First orthognathic approach.
- Treatment plan consensus between the orthodontist and maxillofacial surgeon, aligned with the patient's chief complaint and expectations.
- Underwent orthognathic surgery using the Surgery-First approach without pre-surgical orthodontic treatment.
Key exclusion criteria (3 listed)
- Dentofacial deformities secondary to maxillofacial trauma (e.g., midface retrusion due to Le Fort fractures, or mandibular retrusion due to bilateral condylar fractures).
- Presence of systemic diseases or conditions that contraindicate general anesthesia or orthognathic surgery.
- Presence of psychiatric disorders that may compromise treatment cooperation or the informed consent process.
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 |
|---|---|---|
| Surgery-First Orthognathic SurgeryOrthognathic surgery (Le Fort I, BSSO, or double jaw surgery) performed before orthodontic treatment to correct skeletal discrepancy. | Procedure or surgery | Surgery-First Cohort |
Primary outcome
Three-Dimensional Skeletal and Soft Tissue Changes on Computed Tomography (CT)
Time frame: Baseline (T0), 1 week post-surgery (T1), and 12 months post-surgery (T2)
Evaluation of dentoskeletal and facial soft tissue changes. The measurements include the three-dimensional (3D) spatial displacement of hard and soft tissue landmarks, as well as angular and linear cephalometric parameters (e.g., SNA, SNB, ANB angles) measured on Computed Tomography (CT) images. Comparisons are made across three time points to assess immediate surgical changes and long-term stability.
1 secondary outcome
Pre-surgical Dental Arch Characteristics and Treatment Need Indices
Time frame: Baseline (T0)
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 19 May 2026.
- Individual participant dataSharing planned: No. There is no plan to share individual participant data to protect patient privacy and intellectual property before all publications are completed.
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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 Surgery-First Orthognathic Surgery in people with Skeletal Class III Malocclusion, run by Hanoi Medical University at 1 site in Vietnam.
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 7 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 19 May 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 Vietnam. 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?
Three-Dimensional Skeletal and Soft Tissue Changes on Computed Tomography (CT) (time frame: Baseline (T0), 1 week post-surgery (T1), and 12 months post-surgery (T2)). 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 19 May 2026.