|
KMID : 1149720220120010036
|
|
Clinical Journal of Korean association of Orthodontists
2022 Volume.12 No. 1 p.36 ~ p.52
|
|
|
Orthodontic Treatment with Isolated Mandibular Setback Surgery: Use of 3D Surgical Simulation including Postsurgical Relapse of Mandibular Setback
|
|
Kim Hye-Min
Lim Sung-Hoon
Oh Ji-Su
Jeong Seo-Rin
Kang Shin-Gu
|
|
|
Abstract
|
|
|
|
Isolated mandibular setback along the occlusal plane inevitably causes the development of the vertical bony step (VBS) between the mesial and distal segments of the mandible due to the angular difference between the occlusal plane and mandibular plane. Because the development of VBS causes postsurgical counterclockwise rotation of the mandible, simulation of this counterclockwise rotation should be incorporated into the simulation of surgery and the determination of surgical occlusion. In this case report, a 27-year-old female was treated to correct mandibular prognathism with asymmetry. During presurgical orthodontic treatment, maxillary molars were intruded to reduce the development of VBS during the isolated mandibular setback surgery. Despite this presurgical molar intrusion, 5.6 mm VBS was still developed at the 3D surgical simulation of single jaw surgery. Ideal jaw position was simulated, reducing this VBS to 2.1 mm, resulting in vertical overlaps of molars. To resolve these vertical overlaps or premature contacts, the distal segment was rotated 3.2° clockwise along the hinge axis. This simulation resulted in a surgical occlusion similar to a Class II open bite. During postsurgical orthodontic treatment, the mandible rotated 5.8° counterclockwise with the center of rotation 13 mm inferior to the hinge axis, resolving the VBS almost completely. This was slightly more than the anticipated amount of postsurgical rotation of the mandible. This case report showed that the isolated mandibular setback surgery can be done more predictably by incorporating the postsurgical counterclockwise rotation of the mandible into the simulation of surgery.
|
|
|
KEYWORD
|
|
|
Mandibular prognathism with asymmetry, Isolated mandibular setback, Vetical bony step, Postsurgical counterclockwise rotation, Surgical simulation
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|