Real-time augmented model guidance for mandibular proximal segment repositioning in orthognathic surgery, using...

Area of Science:

• Oral and Maxillofacial Surgery
• Medical Imaging
• Surgical Navigation

Background:

• Accurate repositioning of the mandibular proximal segment (MPS) is crucial in orthognathic surgery.
• Conventional methods lack real-time precision for condyle-in-fossa positioning.
• Existing techniques struggle to pinpoint the exact condyle position during surgery.

Purpose of the Study:

• To develop a real-time, augmented, model-guided surgical method for precise MPS repositioning.
• To improve the accuracy of placing the condyle into its original position within the glenoid fossa.
• To provide surgeons with enhanced visualization of the 3D condyle-fossa relationship during surgery.

Main Methods:

• An improved registration method and a separable electromagnetic tracking tool were utilized.
• Preoperative registration used a novel registration body with optimal fiducial points based on a phantom study.
• A separable frame facilitated real-time tracking of MPS movement via an electromagnetic tracking system.

Main Results:

• The developed method provides real-time augmented visualization of the condyle and fossa.
• Augmented 3D coronal and sagittal views aid in assessing the 3D condyle-fossa positional relationship.
• Root mean square differences of 1.71 ± 0.63 mm (intraoperative) and 1.89 ± 0.22 mm (postoperative) were achieved at condylar landmarks.

Conclusions:

• The novel method enables convenient and accurate MPS repositioning guided by real-time augmented models.
• Surgeons can precisely manage the 3D condyle positional relationship with the glenoid fossa.
• This technique offers a significant advancement in achieving optimal outcomes in orthognathic surgery.