To evaluate the effect of
distraction osteogenesis in correction of
micrognathia accompanying
obstructive sleep apnea syndrome, a total of 28 patients with different severities of
obstructive sleep apnea syndrome underwent mandibular
distraction osteogenesis. A total of 51 distraction devices were placed for bilateral distraction in 23 patients and for unilateral distraction in five patients. The mean age of patients was 21.2 years (range, 3 to 60 years). Eleven patients had
micrognathia accompanying
obstructive sleep apnea syndrome secondary to bilateral temporomandibular joint
ankylosis, and 10 patients had
micrognathia accompanying
obstructive sleep apnea syndrome secondary to unilateral temporomandibular joint
ankylosis. Three patients had developmental
micrognathia accompanying
obstructive sleep apnea syndrome. The other four patients had
micrognathia and concomitant
obstructive sleep apnea syndrome induced by
trauma,
infection, or
tumor resection. Each patient had been evaluated preoperatively and postoperatively with cephalometry and polysomnography. Mandible advancement ranged from 9 to 30 mm (average, 20.4 mm) and was successfully achieved after distraction. Fine new bone formed in the distraction gap when the distraction devices were removed 3 to 4 months after distraction was completed. No
infection or other complications occurred in any patients. Complete curative effects were achieved in nine severe, six moderate, and eight mild
obstructive sleep apnea syndrome patients after distraction, and the other five patients had been improved to the mild level. After distraction was completed, the posterior airway space was increased on average from 4.6 mm to 12.5 mm and the sella-nasion-point B angle was increased on average from 66 degrees to 75 degrees on cephalometric studies. The polysomnographic examination showed that the
apnea hypopnea index was lowered on average from 58.0 to 3.15, and the lowest oxygen saturation was increased on average from 77 percent to 90.3 percent after distraction was completed. The follow-up period was 3 to 61 months (average, 18.1 months). The curative effect was stable and no relapse occurred. Therefore, the authors conclude that mandibular
distraction osteogenesis is an effective method for correcting
micrognathia accompanying
obstructive sleep apnea syndrome. Compared with other current routine
surgical procedures, it has many advantages, such as low risk, simple manipulation, high curative rate, low relapse rate, and stable result. It is presently the most effective method for the treatment of this difficult and complicated disorder.