Telefactor twin version 2

At baseline we obtained medical histories, performed physical examinations, collected self-reported questionnaires, and gathered overnight PSG data. PSG was performed using a digital polygraph system (Grass-Telefactor twin version 2.6, West Warwick, RI, USA) according to standard protocols. Airflow was measured using both an oronasal thermal sensor and a nasal pressure sensor. The data were manually scored according to version 2.2 of the Manual for the Scoring of Sleep and Associated Events published by American Academy of Sleep Medicine.15 The patients who met the inclusion criteria received a customized two-piece OA (SomnoDent, SomnoMed, Sydney, Australia). The treatment protocol for the OA was identical in all centers: the OA was incrementally titrated to the maximum comfortable limit over an acclimatization period lasting 4–6 weeks, and the results were confirmed by a qualified dentist. The degree of mandibular advancement was set by the dentist according to the maximum comfortable (or tolerable) limit for each patient. The patients were followed up 1 month after the completion of OA titration, and the questionnaires and PSG were repeated. Compliance during OA treatment was determined objectively after 1 month using a temperature-sensitive microsensor (Dentitrac, Braebon, Ontario, Canada) embedded in the upper right side of the OA device.