Obstructive sleep apnoea syndrome (OSAS) is potentially a lifethreatening disorder. It is characterized by at least five episodes of apnoea or hypopnoea during sleep lasting for more than 10 seconds. Apnoea or hypopnoea are accompanied by increased respiratory efforts. Maxillo-mandibular advancement belongs to the surgical techniques by which severe OSAS may be influenced. It is a surgical procedure when the upper and lower jaws are moved forward by at least 10 mm. Thus, the muscles fixed to the facial skeleton and upper airway dilatators are moved forwards. The case-report shows a 50-year-old man with the diagnosis of a very severe obstructive sleep apnoea syndrome (Respiratory Disturbances Index 70 and Oxygen Desaturation Index 59). The patient underwent a maxillo-mandibular advancement therapy. Six months after the surgery the patient was without OSAS symptoms, and the x-ray check showed a stable result in terms of both skeletal stability as well as stability of upper airway dilatation. Possible complications and limitations of this surgical technique are also discussed.

        Key words: obstructive sleep apnoea syndrome, maxillo-mandibular advancement, upper airway dilatation