Combined orthodontic and surgical treatment for a patient with Hallermann-Streiff-Francois syndrome, severe obstructive sleep apnea, and history of antiresorptive medication.

Micrognathia and retrognathia, as observed in patients with the Hallermann-Streiff-Francois syndrome, might result in obstructive sleep apnea syndrome. When it becomes severe (apnea-hypopnea index [AHI], ≥30), noninvasive treatment options might be insufficient. An orthognathic treatment with mandibular advancement will increase the upper airway volume, which results in a decrease of apneas.