Volume 17, Number 4, December 2005
| | Three-dimensional Analysis of Facial Soft Tissue Changes after Mandibular Retrusion Surgery |
|---|
Fernando Jose Lores Seijas, Katsuaki Mishima, Toshio Sugahara
Department of Oral and Maxillofacial Reconstructive Surgery, Graduate School of Medicine and Dentistry, Okayama University, Okayama, Japan
Abstract
Objective: To introduce a new method for obtaining 3-dimensional facial images and evaluating soft tissue changes after surgery.
Patients and Methods: Six orthognathic surgery patients who underwent mandibular setback procedures by bilateral sagittal split ramus osteotomy were evaluated. The movements performed during surgery were estimated by lateral cephalogram tracings. The soft tissue changes were evaluated by the use of a non-contact 3-dimensional laser scanner. Changes were analysed by measuring the distance of the normal vectors from the preoperative scan surface to the surface of the postoperative scan at each pixel. The shape change pattern was analysed at the mental and inferior lip areas.
Results: The amount of mandibular retrusion ranged from 4.2 mm to 17.1 mm at the bony pogonion. The 3-dimensional scans showed that all patients presented a similar change pattern in which the greatest amount of soft tissue change was close to the midline and gradually diminished laterally.
Conclusions: The scanning method used in this study to obtain the facial scan was simple, fast, and reliable. Since the direction of the normal vectors analysed was dependent on the facial surface, change was analysed in multiple directions and represented by a coloured facial map. Despite the statistical limitations of this system, it provides the clinician with a visual and comprehensible image to represent shape changes.
Key words: Face, Imaging, three-dimensional, Lasers, Surgery
Asian J Oral Maxillofac Surg. 2005;17:230-237.
 |
|
|
|
