Mandibular advancement devices: indications and predictors of treatment outcome. A review

Obstructive sleep apnea syndrome (OSAS) is a chronic sleep and respiratory disorder, which causes a partial or total obstruction of the air passage at the upper airway level. Mandibular advancement devices (MADs) have been used in the treatment of snoring, but may be a valid alternative to the continuous nasal positive airway pressure (CPAP) for certain OSAS cases. Therapy by means of MADs arises the interest of the scientific community and now there are many sleep-centres where dentists work as experts in sleep disorders. MADs are instruments of value because they are simple to use, reversible, portable and they generally have a low complication rate. They mechanically increase the oropharyngeal space by advancing the mandible and/or the tongue and reduce pharyngeal collapsibility. More than 60 different MADs are in use, with considerable variations in design. Several studies show that their systematic use produces an evident improvement in the global quality of life as well as in the symptoms of patients with OSAS, especially sleepiness. Even though significant progress has been made in proving the efficacy of MADs for OSAS, the ability to predict the treatment outcome and hence pre-select suitable candidates for this treatment still remains in its early stage. The first aim of this review is to supply to the clinician informations on the cephalometric and polysomnographic parameters that can be used to predict the efficacy of the outcome of MAD therapy in OSAS. Moreover, we examine the cases for which the use of a MAD is indicated.