Post-operative soft tissue changes in patients with mandibular prognathism after bimaxillary surgery.
OBJECTIVE
The objective of this study was to evaluate the three-dimensional soft tissue changes observed over time after bimaxillary surgery for mandibular prognathism using cone-beam computed tomography (CBCT) superimposed imaging.


METHODS
CBCT scans were obtained for 25 patients before bimaxillary surgery (T0), at 2 months after surgery (T1) and at 6 months after surgery (T2). Cephalometric variables from the reoriented volumetric images were measured and compared at T0, T1, and T2. The quantitative surface displacement in the middle and the lower third of the facial soft tissue using CMF tools was assessed by superimposing the T0 and T1 or T0 and T2 3D images.


RESULTS
The soft tissue in middle third of face moved forward at T1 and significantly moved backward from T1 to T2 (Ch-Al, p < 0.001; Al, p < 0.05; Pn, p < 0.05). Most of the soft tissue changes from T1 to T2 were not correlated with the hard tissue changes (p > 0.05), while the cheeks were positively correlated with the soft tissue around them (Exo-Al, p < 0.01; Ch-Al, p < 0.01).


CONCLUSIONS
Post-operative soft tissue changes occurred in the middle third of the face and are considered to be more complex than the changes in the lower third of face. Therefore, soft tissue assessment at least 6 months after surgery is desirable.
Department of Orthodontics, Kangdong Sacred Heart Hospital, Hallym University Medical Center, Gil-dong 445, Gangdong-gu, Seoul 134-701, Republic of Korea.
Kyung-Min
KM
Oh
Sung-Kyung
SK
Seo
Jeong-Eon
JE
Park
Hyoung-Seob
HS
Sim
Lucia H S
LH
Cevidanes
Yoon-Ji R
YJ
Kim
Yang-Ho
YH
Park
D000293:Adolescent; D000328:Adult; D001860:Bone Plates; D001863:Bone Screws; D002508:Cephalometry / Q000379:methods; D002610:Cheek / Q000000981:diagnostic imaging; D002680:Chin / Q000000981:diagnostic imaging; D054893:Cone-Beam Computed Tomography / Q000379:methods; D005143:Eyelids / Q000000981:diagnostic imaging; D005145:Face / Q000000981:diagnostic imaging; D005260:Female; D005500:Follow-Up Studies; D063172:Genioplasty / Q000379:methods; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008046:Lip / Q000000981:diagnostic imaging / Q000601:surgery; D008297:Male; D008313:Malocclusion, Angle Class III / Q000601:surgery; D008334:Mandible / Q000000981:diagnostic imaging / Q000601:surgery*; D008437:Maxilla / Q000000981:diagnostic imaging / Q000601:surgery*; D009295:Nasal Bone / Q000000981:diagnostic imaging; D055171:Nasal Cartilages / Q000000981:diagnostic imaging / Q000601:surgery; D056948:Orthognathic Surgical Procedures / Q000379:methods; D019340:Osteotomy, Le Fort / Q000379:methods; D059229:Osteotomy, Sagittal Split Ramus / Q000379:methods; D011378:Prognathism / Q000601:surgery*; D012189:Retrospective Studies; D055815:Young Adult