Correlation between skeletal and dental changes after mandibular setback surgery-first orthodontic treatment: Cone-beam computed tomography-generated half-cephalograms.
10.4041/kjod.2015.45.2.59
- Author:
Chang Hoon RHEE
1
;
Youn Kyung CHOI
;
Yong Il KIM
;
Seong Sik KIM
;
Soo Byung PARK
;
Woo Sung SON
Author Information
1. Private Practice, Busan, Korea.
- Publication Type:Original Article
- Keywords:
Three-dimensional cephalometrics;
Computed tomography;
Class III orthognathic surgery
- MeSH:
Cone-Beam Computed Tomography;
Congenital Abnormalities;
Female;
Humans;
Male;
Malocclusion;
Mandible;
Maxilla;
Retrospective Studies;
Vertical Dimension
- From:The Korean Journal of Orthodontics
2015;45(2):59-65
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVE: To investigate skeletal and dental changes after application of a mandibular setback surgery-first orthodontic treatment approach in cases of skeletal Class III malocclusion. METHODS: A retrospective study of 34 patients (23 men, 11 women; mean age, 26.2 +/- 6.6 years) with skeletal Class III deformities, who underwent surgery-first orthodontic treatment, was conducted. Skeletal landmarks in the maxilla and mandible at three time points, pre-treatment (T0), immediate-postoperative (T1), and post-treatment (T2), were analyzed using cone-beam computed tomography (CBCT)-generated half-cephalograms. RESULTS: The significant T0 to T1 mandibular changes occurred -9.24 +/- 3.97 mm horizontally. From T1 to T2, the mandible tended to move forward 1.22 +/- 2.02 mm, while the condylar position (Cd to Po-perpendicular plane) shifted backward, and the coronoid process (Cp to FH plane) moved vertically. Between T1 and T2, the vertical dimension changed significantly (p < 0.05). Changes in the vertical dimension were significantly correlated to T1 to T2 changes in the Cd to Po-perpendicular plane (r = -0.671, p = 0.034), and in the Cp to FH plane (r = 0.733, p = 0.016), as well as to T0 to T1 changes in the Cp to Po-perpendicular plane (r = 0.758, p = 0.011). CONCLUSIONS: Greater alterations in the vertical dimension caused larger post-treatment (T2) stage skeletal changes. Studying the mandibular position in relation to the post-surgical vertical dimension emphasized the integral importance of vertical dimension control and proximal segment management to the success of surgery-first orthodontic treatment.