Obwegeser II osteotomy (transoral angle osteotomy) for open bite with skeletal class III deformity.
BACKGROUND
This study evaluated postoperative stability after Obwegeser II osteotomy (transoral angle osteotomy, first reported by Obwegeser 1973) for severe open bite with mandibular prognathism.


METHODS
This retrospective study reviewed 20 consecutive patients who underwent only mandibular Obwegeser II osteotomy to correct open bite and mandibular prognathism. Lateral cephalograms were evaluated preoperatively (T1), immediate postoperatively (T2) and at least 6 months after the surgery (T3). Surgical and postsurgical changes in cephalometric measurements were evaluated statistically.


RESULTS
Open bite with skeletal class III malocclusion was corrected by the Obwegeser II osteotomy alone. After an average of 9.9 ± 5.2 mm of mandibular setback with open bite closure (T2-T1, over-bite change, 5.7 ± 2.4 mm) by counter-clockwise rotation of the mandible, the patients showed 0.8 ± 1.7 mm of horizontal relapse (p > 0.05), 1.1 ± 1.7 mm of vertical relapse at the B point (p = 0.011) and -0.2 ± 1.6 mm of over-bite change postoperatively (T3-T2).


CONCLUSIONS
With the adequate control of the condylar position with rigid internal fixation, Obwegeser II osteotomy showed acceptable stability after the correction of open bite with mandibular prognathism without a simultaneous maxillary osteotomy. An isolated Obwegeser II osteotomy can be considered a reliable option in cases with moderate to severe open bite with mandibular prognathism when the maxillary osteotomy is not needed if the patients have a well-positioned maxilla.
Department of Oral & Maxillofacial Surgery (Head: Prof. Tae-Geon Kwon), School of Dentistry, Kyungpook National University, Samduck 2 Ga, Jung Gu, Daegu 700-421, South Korea. Electronic address: kwondk@knu.ac.kr.
Tae-Geon
TG
Kwon
Department of Oral & Maxillofacial Surgery (Head: Prof. Tae-Geon Kwon), School of Dentistry, Kyungpook National University, Samduck 2 Ga, Jung Gu, Daegu 700-421, South Korea.
KwangMyung
K
Na
Department of Oral & Maxillofacial Surgery (Head: Prof. Tae-Geon Kwon), School of Dentistry, Kyungpook National University, Samduck 2 Ga, Jung Gu, Daegu 700-421, South Korea.
Sang-Han
SH
Lee
D000328:Adult; D059925:Anatomic Landmarks / Q000473:pathology; D001860:Bone Plates; D001863:Bone Screws; D002508:Cephalometry / Q000379:methods; D004424:Ear Canal / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008313:Malocclusion, Angle Class III / Q000601:surgery*; D008334:Mandible / Q000473:pathology / Q000601:surgery; D008335:Mandibular Condyle / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D009295:Nasal Bone / Q000473:pathology; D024343:Open Bite / Q000601:surgery*; D009915:Orbit / Q000473:pathology; D059229:Osteotomy, Sagittal Split Ramus / Q000145:classification / Q000295:instrumentation / Q000379:methods*; D011378:Prognathism / Q000601:surgery; D012008:Recurrence; D012189:Retrospective Studies; D012399:Rotation; D012658:Sella Turcica / Q000473:pathology; D014716:Vertical Dimension; D055815:Young Adult
Mandibular prognathism; Obwegeser II osteotomy; Open bite; Transoral angle ostectomy