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Maxillary Patient Specific Implants in Bimaxillary Orthognathic Surgery

Not Applicable
Recruiting
Conditions
Malocclusion, Angle Class II
Retrognathia
Interventions
Device: Conventional mini-plates
Device: Patient-specific implants
Registration Number
NCT06297109
Lead Sponsor
Esbjerg Hospital - University Hospital of Southern Denmark
Brief 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. 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.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
60
Inclusion Criteria
  • Mandibular retrognathia
  • Occlusion class II
  • Three-piece Le Fort I osteotomy, as part of bimaxillary orthognathic surgery with or without genioplasty
Exclusion Criteria
  • Cleft lip
  • Craniofacial syndromes
  • Former trauma
  • Obstructive sleep apnea

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
ControlConventional mini-platesParticipants treated with conventional mini-plates for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery.
InterventionPatient-specific implantsParticipants treated with patient-specific implants for Le Fort I osteotomy and genioplasty in bimaxillary orthognathic surgery.
Primary Outcome Measures
NameTimeMethod
The stability of the upper airwayTwo 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).

The accuracy of segmental Le Fort I bone movementsTwo 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 movementsTwo 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.

Secondary Outcome Measures
NameTimeMethod
The Epworth Sleepiness Scale questionnairePreoperative and two years postoperative

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.

The STOP-BANG - Snorting, Tiredness, Observed apnea, blood Pressure, BMI, Age, Neck circumference, Gender questionnairePreoperative and two years postoperative

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.

The Jaw Functional Limitation ScalePreoperative and two years postoperative

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.

The occlusion including horizontal/vertical overlapPreoperative, two weeks postoperative and two years postoperative

The horizontal/vertical dental overlap is measured using a ruler in millimeters.

The Diagnostic Criteria for Temporomandibular Disorders Symptom questionnairePreoperative and two years postoperative

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.

Trial Locations

Locations (1)

University Hospital of Southern Denmark

🇩🇰

Esbjerg, Denmark

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