RetrognathiaNCT06297109
Maxillary Patient Specific Implants in Bimaxillary Orthognathic Surgery
A study testing Patient-specific implants and Conventional mini-plates in people with Retrognathia and Malocclusion, Angle Class II, run by Esbjerg Hospital - University Hospital of Southern Denmark at 1 site in Denmark.
Trial summary
Orthognathic surgery is a type of jaw surgery where a surgeon cuts the bones of the upper and lower jaw and places them better. There are two ways they can put the bones in the correct place and keep them in place after the surgery. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Retrognathia, Malocclusion, Angle Class II
- What is being tested?
- Patient-specific implants and Conventional mini-plates
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- 1 siteDenmark
- Study dates
- 12 Sep 2023to 31 Aug 2027
- 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 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Mandibular retrognathia
- Occlusion class II
- Three-piece Le Fort I osteotomy, as part of bimaxillary orthognathic surgery with or without genioplasty
Who cannot join
- Cleft lip
- Craniofacial syndromes
- Former trauma
- Obstructive sleep apnea
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Maxillary Patient Specific Implants in Bimaxillary Orthognathic Surgery: A Quality Assessment by Novel Automated Virtual Methods
Orthognathic surgery is a type of jaw surgery where a surgeon cuts the bones of the upper and lower jaw and places them better. There are two ways they can put the bones in the correct place and keep them in place after the surgery. One way, called the "conventional method", is to use a 3D-printed guide called a splint to set the bones in the right place and then screw the bones together using metal plates that the surgeon bends into shape to fit during the surgery. Another way is to use a patient-specific implants (PSI) that has been 3D-printed in titanium beforehand that because of its unique shape both places and keeps all the bones in the correct place after they are screwed in. Both ways of doing it are golden standards, meaning they are already approved.
Measuring the accuracy of the surgery is done by comparing the positions of the bones after the surgery with the intended positions of those bones, according to the surgical plan. The closer the achieved position of each bone is to the intended position, the more accurate the result.
Read more
Measuring the stability of the surgery is done by comparing the positions of the bones after the surgery with the positions of the bones two years later. The less the position is changed, the more stable the result.
The goal of this clinical trial is to see how accurate and stable PSIs are in orthognathic surgery when the maxilla is split in 3 pieces, and to compare them with the conventional method in patients with overjet or overbite. The main questions it aims to answer are:
- Does using PSIs provide accurate movements of the maxilla pieces?
- Does using PSIs provide more accurate movements of the maxilla pieces than the conventional method?
- Does using PSIs provide stable movements of the maxilla pieces after 2 years?
- Does using PSIs provide more stable movements of the maxilla pieces than the conventional method?
Participants will get orthognathic surgery as part of their normal orthodontic treatment.
Investigators will compare the PSI and conventional groups to see if the PSIs are more accurate than the conventional method.
- Conditions
- Retrognathia, Malocclusion, Angle Class II
- Being tested
- Patient-specific implants, Conventional mini-plates
- Keywords
- Orthognathic Surgery, Computer-Assisted Surgery, Three-dimensional Imaging, Cone-Beam Computed Tomography, Virtual Surgical Planning, Maxillary Osteotomy, Mandibular Osteotomy, Genioplasty, Osteotomy, Le Fort, Patient-Specific Implants, Accuracy, Stability
- Medical subject headings
- Retrognathia, Malocclusion, Angle Class II
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Patient-specific implantsDevice
Application of patient-specific implants for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery.
Conventional mini-platesDevice
Application of conventional mini-plates for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery.
| Study group | Role | What they receive |
|---|---|---|
| Intervention | Experimental | Participants treated with patient-specific implants for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery. Receives: Device: Patient-specific implants |
| Control | Active comparator | Participants treated with conventional mini-plates for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery. Receives: Device: Conventional mini-plates |
What is being measured
The primary outcome is the main question the study is designed to answer.
The accuracy of segmental Le Fort I bone movements
The three-dimensional linear and angular accuracy are measured as differences between the planned and postoperative positions of all repositioned bone segments. Measurements are performed on pre- and two weeks postoperative cone-beam computed tomography scans using the Mimics Innovation Suite software (Materialise NV, Leuven, Belgium). An error measure above 2 mm and/or 4 degrees is categorized as inaccurate.
Measured: Two weeks postoperative
The stability of segmental Le Fort I bone movements
The three-dimensional linear and angular stability are measured as differences between the short- and long-term postoperative positions of all repositioned bone segments. Measurements are performed on two weeks and two years postoperative cone-beam computed tomography scans using the Mimics Innovation Suite software (Materialise NV, Leuven, Belgium). An error measure above 2 mm and/or 4 degrees is categorized as unstable.
Measured: Two years postoperative
The stability of the upper airway
The stability of the upper airway space is measured as voluminal and cross-sectional area differences between the short- and long-term postoperative airway in mm3 and mm2, respectively. Measurements are performed on two weeks and two years postoperative cone-beam computed tomography scans using the Mimics Innovation Suite software (Materialise NV, Leuven, Belgium).
Measured: Two years postoperative
Secondary outcomes (5)
The Diagnostic Criteria for Temporomandibular Disorders Symptom questionnaire
Has Yes/No questions for the patient, used by the clinician to diagnose according to specific diagnostic criteria. See:
Schiffman E, Ohrbach R, Truelove E, Look J, Anderson G, Goulet JP, List T, Svensson P, Gonzalez Y, Lobbezoo F, Michelotti A. Diagnostic criteria for temporomandibular disorders (DC/TMD) for clinical and research applications: recommendations of the International RDC/TMD Consortium Network and Orofacial Pain Special Interest Group. Journal of oral \& facial pain and headache. 2014;28(1):6.
Measured: Preoperative and two years postoperative
The Jaw Functional Limitation Scale
JFLS-8 measures global functional limitation of the jaw. It has 8 questions scored 0-10, where 10 is the most severe level jaw limitation in the last month.
Measured: Preoperative and two years postoperative
The STOP-BANG - Snorting, Tiredness, Observed apnea, blood Pressure, BMI, Age, Neck circumference, Gender questionnaire
It assesses risk/likelihood of obstructive sleep apnea (OSA). It has 8 yes/no questions, and the number of yes answers are counted towards the score as follows:
0-2: low risk of OSA. 3-4: moderate risk of OSA. 5-8: high risk of OSA.
Measured: Preoperative and two years postoperative
The Epworth Sleepiness Scale questionnaire
Is scored by the sum of the responses to eight questions, on a scale 0-24 where 24 is the highest sleepiness. A score above 10 is considered as significant daytime sleepiness and is considered abnormal.
Measured: Preoperative and two years postoperative
The occlusion including horizontal/vertical overlap
The horizontal/vertical dental overlap is measured using a ruler in millimeters.
Measured: Preoperative, two weeks postoperative and two years postoperative
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Mar 2024
- Study start12 Sep 2023
- Primary completion31 Aug 2027 (estimated)
- Study completion31 Aug 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for RetrognathiaStudies 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
- Masking
- Triple blind
- Who is masked
- Participant, Care provider, Investigator
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Esbjerg Hospital - University Hospital of Southern Denmark
- Sponsor type
- University, hospital or other
- Collaborators
- University of Southern Denmark
- Responsible party
- Sponsor
- Investigators
- Else M Pinholt, dr.odont., Study chair, University Hospital of Southern Denmark, EsbjergAlexandru Diaconu, m.sc., Principal investigator, University Hospital of Southern Denmark, EsbjergMichael B Holte, ph.d., Study director, University Hospital of Southern Denmark, Esbjerg
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06297109
- Sponsor's protocol ID
- S-20230033
- Status last verified
- Jan 2026
- First submitted
- 17 Jan 2024
- Last updated
- 27 Jan 2026
- 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 27 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Maxillary Patient Specific Implants in Bimaxillary Orthognathic Surgery: A Quality Assessment by Novel Automated Virtual Methods
- ClinicalTrials.gov ID
- NCT06297109
- Acronym / sponsor ID
- S-20230033
- Conditions
- Retrognathia, Malocclusion, Angle Class II
- Keywords
- Orthognathic Surgery, Computer-Assisted Surgery, Three-dimensional Imaging, Cone-Beam Computed Tomography, Virtual Surgical Planning, Maxillary Osteotomy, Mandibular Osteotomy, Genioplasty
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 60 participants (estimated)
- Lead sponsor
- Esbjerg Hospital - University Hospital of Southern DenmarkUniversity, hospital or other
- Collaborators
- University of Southern Denmark
- Study start
- 12 Sep 2023 (actual)
- Primary completion
- 31 Aug 2027 (estimated)
- Study completion
- 31 Aug 2027 (estimated)
- First posted
- 7 Mar 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.
Orthognathic surgery is a type of jaw surgery where a surgeon cuts the bones of the upper and lower jaw and places them better. There are two ways they can put the bones in the correct place and keep them in place after the surgery. One way, called the "conventional method", is to use a 3D-printed guide called a splint to set the bones in the right place and then screw the bones together using metal plates that the surgeon bends into shape to fit during the surgery. Another way is to use a patient-specific implants (PSI) that has been 3D-printed in titanium beforehand that because of its unique shape both places and keeps all the bones in the correct place after they are screwed in. Both ways of doing it are golden standards, meaning they are already approved.
Measuring the accuracy of the surgery is done by comparing the positions of the bones after the surgery with the intended positions of those bones, according to the surgical plan. The closer the achieved position of each bone is to the intended position, the more accurate the result.
Measuring the stability of the surgery is done by comparing the positions of the bones after the surgery with the positions of the bones two years later. The less the position is changed, the more stable the result.
The goal of this clinical trial is to see how accurate and stable PSIs are in orthognathic surgery when the maxilla is split in 3 pieces, and to compare them with the conventional method in patients with overjet or overbite. The main questions it aims to answer are:
- Does using PSIs provide accurate movements of the maxilla pieces?
- Does using PSIs provide more accurate movements of the maxilla pieces than the conventional method?
- Does using PSIs provide stable movements of the maxilla pieces after 2 years?
- Does using PSIs provide more stable movements of the maxilla pieces than the conventional method?
Participants will get orthognathic surgery as part of their normal orthodontic treatment.
Investigators will compare the PSI and conventional groups to see if the PSIs are more accurate than the conventional method.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, care provider, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Intervention | Experimental | Device: Patient-specific implantsParticipants treated with patient-specific implants for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery. |
| Control | Active comparator | Device: Conventional mini-platesParticipants treated with conventional mini-plates for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Mandibular retrognathia
- Occlusion class II
- Three-piece Le Fort I osteotomy, as part of bimaxillary orthognathic surgery with or without genioplasty
Key exclusion criteria (4 listed)
- Cleft lip
- Craniofacial syndromes
- Former trauma
- Obstructive sleep apnea
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 |
|---|---|---|
| Patient-specific implantsApplication of patient-specific implants for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery. | Device | Intervention |
| Conventional mini-platesApplication of conventional mini-plates for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery. | Device | Control |
Primary outcome
The accuracy of segmental Le Fort I bone movements
Time frame: Two weeks postoperative
The three-dimensional linear and angular accuracy are measured as differences between the planned and postoperative positions of all repositioned bone segments. Measurements are performed on pre- and two weeks postoperative cone-beam computed tomography scans using the Mimics Innovation Suite software (Materialise NV, Leuven, Belgium). An error measure above 2 mm and/or 4 degrees is categorized as inaccurate.
The stability of segmental Le Fort I bone movements
Time frame: Two years postoperative
The three-dimensional linear and angular stability are measured as differences between the short- and long-term postoperative positions of all repositioned bone segments. Measurements are performed on two weeks and two years postoperative cone-beam computed tomography scans using the Mimics Innovation Suite software (Materialise NV, Leuven, Belgium). An error measure above 2 mm and/or 4 degrees is categorized as unstable.
The stability of the upper airway
Time frame: Two years postoperative
The stability of the upper airway space is measured as voluminal and cross-sectional area differences between the short- and long-term postoperative airway in mm3 and mm2, respectively. Measurements are performed on two weeks and two years postoperative cone-beam computed tomography scans using the Mimics Innovation Suite software (Materialise NV, Leuven, Belgium).
5 secondary outcomes
The Diagnostic Criteria for Temporomandibular Disorders Symptom questionnaire
Time frame: Preoperative and two years postoperative
The Jaw Functional Limitation Scale
Time frame: Preoperative and two years postoperative
The STOP-BANG - Snorting, Tiredness, Observed apnea, blood Pressure, BMI, Age, Neck circumference, Gender questionnaire
Time frame: Preoperative and two years postoperative
The Epworth Sleepiness Scale questionnaire
Time frame: Preoperative and two years postoperative
The occlusion including horizontal/vertical overlap
Time frame: Preoperative, two weeks postoperative and two years postoperative
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 27 Jan 2026.
Related trials for Retrognathia
RecruitingObservational study
Natural History of Craniofacial Anomalies and Developmental Growth Variants
Prognathism, Retrognathism
Not yet recruiting
Treatment of Mandibular Overjet in Children With Maxillary Retrognathism
Maxillary Retrognathism, Children
Recruiting
Using Chin Bone Rings for Sinus Lifting and Dental Implants in One Surgery
Maxillary Deficiency, Bone Resorption
Active, not recruitingObservational study
Comparative Evaluation of Functional and Aesthetic Outcomes of Box and Mini-Wing Genioplasty Techniques
Class II Malocclusion, Dentofacial Deformities
Recruiting
Leaf Expander Versus Hyrax Expander in Mixed Dentition Patients With Posterior Crossbite.
Posterior Crossbite, Maxilla; Hypoplasia
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.
Else M Pinholt, dr.odont. study chair
University Hospital of Southern Denmark, Esbjerg
Alexandru Diaconu, m.sc. principal investigator
University Hospital of Southern Denmark, Esbjerg
Michael B Holte, ph.d. study director
University Hospital of Southern Denmark, Esbjerg
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Patient-specific implants and Conventional mini-plates in people with Retrognathia and Malocclusion, Angle Class II, run by Esbjerg Hospital - University Hospital of Southern Denmark at 1 site in Denmark.
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 3 inclusion and 4 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: under way, not looking for participants, as of the sponsor's last update on 27 Jan 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 Denmark. 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?
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?
The accuracy of segmental Le Fort I bone movements (time frame: Two weeks postoperative). The study lists 3 primary outcomes in all. 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 27 Jan 2026; AzTrials last refreshed its copy on 1 Nov 2026.