J Korean Assoc Oral Maxillofac Surg.  2014 Feb;40(1):32-36. 10.5125/jkaoms.2014.40.1.32.

Unilateral intraoral vertical ramus osteotomy based on preoperative three-dimensional simulation surgery in a patient with facial asymmetry

• Lee JW
• Kim MK
• Kang SH

• KMID: 1960970
• DOI: http://doi.org/10.5125/jkaoms.2014.40.1.32

Abstract

Preoperative surgical simulation in orthognathic surgery has progressed in recent years; the movement of the mandible can be anticipated through three-dimensional (3D) simulation surgery before the actual procedure. In this case report, the mandible was moved to the intended postoperative occlusion through preoperative surgical 3D simulation. Right-side condylar movement change was very slight in the surgical simulation, suggesting the possibility of mandibular surgery that included only left-side ramal osteotomy. This case report describes a patient with a mild asymmetric facial profile in which the mandibular menton had been deviated to the right and the lips canted down to the left. Before surgery, three-dimensional surgical simulation was used to evaluate and confirm a position for the condyle as well as the symmetrical postoperative state of the face. Facial asymmetry was resolved with minimal surgical treatment through unilateral intraoral vertical ramus osteotomy on the left side of the mandible. It would be a valuable complement for the reduction of the surgical treatment if one could decide with good predictability when an isolated intraoral vertical ramus osteotomy can be done without a compensatory osteotomy on the contralateral side.

Keyword

Surgical simulation; Orthognathic surgery; Three-dimensional simulation surgery; Intraoral vertical ramus osteotomy; Facial asymmetry

MeSH Terms

Complement System Proteins
Facial Asymmetry*
Humans
Lip
Mandible
Orthognathic Surgery
Osteotomy*
Complement System Proteins

Figure

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  Fig. 1 A-C. Initial pretreatment extraoral photographs. D. Intraoral photograph.

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  Fig. 2 Mandibular simulation surgery. A. Preoperative three-dimensional (3D) skeletal image overlapped with current occlusion digital cast images. B, C. 3D images of the mandibular setback (blue) repositioning under bilateral ramus osteotomy was simulated and evaluated according to the planned postoperative occlusion images. D. Images were overlaid consisting of the current mandible image (pink) and the repositioned mandible image (blue) in the 3D surgical simulation with the planned postoperative occlusion state.

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  Fig. 3 A. Discrepancies were color-coded and evaluated in the three-dimensional (3D) image based on the range of difference values in the superimposed preoperative mandibular image and the simulated repositioned mandible. B. Discrepancies of the right condyle were evaluated in the 3D image based on the moved range of 3D coordinate planes in the superimposed preoperative mandibular image (sky blue) and the simulated repositioned mandible (red).

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  Fig. 4 Final surgical simulation image, with only left mandibular ramus osteotomy. Final surgical simulation with only left mandibular ramus osteotomy (blue) was confirmed, and decided as final surgical plan.

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  Fig. 5 Extraoral photographs (A, B), intraoral photograph (C), and three-dimensional facial computed tomography (D) of the final result.

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  Fig. 6 Discrepancies were color-coded in the three-dimensional image based on the range of difference values in the superimposed preoperative mandibular image and the final result mandible.

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