Korean J Orthod.  2023 Mar;53(2):99-105. 10.4041/kjod22.077.

Three-dimensional evaluation of mandibular width after mandibular asymmetric setback surgery using sagittal split ramus osteotomy

• Kim SS
• Kim SH
• Kim YI
• Park SB

• KMID: 2540949
• DOI: http://doi.org/10.4041/kjod22.077

Abstract

Objective
The study aimed to evaluate the changes in mandibular width after sagittal split ramus osteotomy (SSRO) in patients with mandibular asymmetric prognathism using cone-beam computed tomography (CBCT).
Methods
Seventy patients who underwent SSRO for mandibular setback surgery were included in two groups, symmetric (n = 35) and asymmetric (n = 35), which were divided according to the differences in their right and left setback amounts. The mandibular width was evaluated three-dimensionally using CBCT images taken immediately before surgery (T1), 3 days after surgery (T2), and 6 months after surgery (T3). Repeated measures analysis of variance was applied to verify the differences in mandibular width statistically.
Results
Both groups showed a significant increase in the mandibular width at T2, followed by a significant decrease at T3. No significant difference was observed between T1 and T3 in any of the measurements. No significant differences were found between the two groups (p > 0.05). Conclusions: After mandibular asymmetric setback surgery using SSRO, the mandibular width increased immediately but returned to its original width 6 months after surgery.

Keyword

Class III orthognathic surgery; Computed tomography; Facial asymmetry

Figure

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  Figure 1 Hard tissue landmarks. See Table 2 for definitions of each landmark.

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  Figure 2 Soft tissue landmarks. See Table 2 for definitions of each landmark.

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  Figure 3 Changes of mandibular width in the asymmetric group.

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