The Effect of mandible advancement splints in mild, moderate, and severe obstructive sleep apnea-the need for sleep registrations during follow up

Abstract

Objective and design: Our aim was to evaluate the effect of mandible advancement splint (MAS) in mild, moderate, and severe obstructive sleep apnea (OSA). We also determined, if and in which OSA-groups the adequate forward movement in MAS could be quantified without sleep registration for different OSA levels. A retrospective study.

Settings: The effect of MAS was measured with clinical methods and by sleep registration.

Participants: The series consisted of 103 patients, 75 males and 28 females (mean age 52 years) suffering from mild (32 per cent), moderate (32 per cent), or severe (36 per cent) OSA, who were treated with MAS at Helsinki University Hospital, Finland during the years 2011-2012. Seventy per cent of the patients had tried continuous positive airway pressure (CPAP) before MAS.

Results: The lower the body mass index (BMI) was the bigger the probability was to get apnea/hypopnea index (AHI) values <5 per hour with MAS (P < 0.01). The total AHI decreased significantly from the baseline with MAS: 23 per hour (range 5-89) to 6 per hour (range 0.3-54), (P < 0.001). The mean oxygen desaturation index (ODI4%) improved significantly from 16 per hour (range 1-76) to 5.3 per hour (range 0.2-49), (P < 0.01), and the minimum oxygen saturation improved significantly from 84 per cent (67-91) to 87 per cent (68-93), (P < 0.01). The reduction of AHI with MAS was significantly bigger in patients with a previous CPAP experience (73 per cent) than those who did not tried CPAP therapy. The positive correlation was found between the decrease in AHI and the increase of the protrusion in MAS.

Conclusion: Both sleep recordings and subjective indicators demonstrated that MAS therapy was successful in OSA based on ESS, total AHI, ODI4%, and minimum oxygen saturation values. It seems useful to increase the protrusion at its maximal clinical tolerance. An experienced dentist could make therapeutically decision concerning the follow up of MAS efficacy regardless of the result of sleep study. We suggest that MAS is a valuable treatment alternative for CPAP. However, the previous use of CPAP with MAS as well as lower baseline BMI seem to have a positive correlation with the success of MAS therapy.