Background Maxillomandibular advancement surgery (MMA) has demonstrated high success rates, improving both the apnea-hypopnea index and associated patient' quality of life (QOL), in patients diagnosed with obstructive sleep apnea syndrome (OSAS). However, clinical relapse has been described in the target population, especially when associated with significant weight gain. Literature reporting the long-term impact of MMA for OSAS is lacking. The surgeons of the Division of Maxillofacial Surgery already started to perform this type of surgery in 1995.

Objectives The investigators aim to evaluate the long-term (minimum 15 years post-surgery) biologic and QOL impact of MMA in patients with OSAS. The biologic impact refers to the stability of hard and soft tissues and polysomnographic results.

Study design Retrospective study Both pre- en postoperative clinical imaging, polysomnography and quality of life questionnaires will be retrieved from all patients that were surgically treated with an MMA by one surgeon (CDC) between 01/11/1995 and 01/12/1999.

Conclusion Short-term data have shown high success rates for MMA in OSAS patients. However, long-term data are lacking. This retrospective study might provide us with more information about the incidence of clinical relapse fifteen to twenty years after surgery.

Inclusion Criteria:

• clinically confirmed diagnosis of OSAS
• treated with an MMA between 01/11/1995 and 01/12/1999 by one surgeon (CDC)

Exclusion Criteria:

• not following abovementioned criteria

All patients (n=10/12) with a clinically confirmed diagnosis of OSAS, that were treated with an MMA between 01/11/1995 and 01/12/1999 by one surgeon (CDC)