An interventional study of Patient-specific implants and Conventional mini-plates in Retrognathia and Malocclusion, Angle Class II, sponsored by Esbjerg Hospital - University Hospital of Southern Denmark. Active, not recruiting at 1 site in Denmark. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-01-27.
Sponsored by Esbjerg Hospital - University Hospital of Southern Denmark · Not applicable, Interventional, and Treatment
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:
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.
62 studies on the registry are indexed under Retrognathia; 15 are open to participants now.
This study's planned enrollment of 60 is above the median of 34 across 52 interventional studies indexed under Retrognathia.
Browse Retrognathia studies →Esbjerg Hospital - University Hospital of Southern Denmark is the lead sponsor of 50 studies on the registry; 15 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Participants treated with patient-specific implants for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery.
Device: Patient-specific implants
Participants treated with conventional mini-plates for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery.
Device: Conventional mini-plates
Application of patient-specific implants for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery.
Application of conventional mini-plates for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery.
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.
Time frame: 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.
Time frame: 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).
Time frame: Two years postoperative
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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: Preoperative and two years postoperative
The occlusion including horizontal/vertical overlap
The horizontal/vertical dental overlap is measured using a ruler in millimeters.
Time frame: Preoperative, two weeks postoperative and two years postoperative
Started Sep 2023 (actual). Primary completion is estimated for Aug 2027, 47 months after the start.
Of 30 interventional studies with no phase under Retrognathia, half reached primary completion within 19 months of starting (the median), counting those still running; a quarter within 14 and three quarters within 35. This study's planned 47 months is above that.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
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Esbjerg Hospital - University Hospital of Southern Denmark