Tongue position controller as an alternative treatment for obstructive sleep apnea

Abstract

Obstructive sleep apnea (OSA) is a common, but underdiagnosed, public health problem that predisposes the patient to higher cardiovascular morbidity and mortality. Nasal continuous positive airway pressure (nCPAP) has been established as a standard treatment for OSA for nearly three decades, whereas oral appliances (i.e., mandibular repositioning splint and tongue retaining device) have been prescribed for patients with mild to moderate OSA and/or who have failed to respond to nCPAP [1–3]. A tongue retaining device is particularly recommended in patients who are contraindicated for mandibular repositioning splints due to an insufficient number of teeth, severe periodontal disease, temporomandibular joint problems, and so on [1]. To improve the patency of the pharyngeal airway, this device holds the tongue at a protruded position by negative pressure that is generated within the anterior socket, thus possibly displacing the tongue base ventrally. Dort and Brant [4] succeeded in reducing the respiratory disturbance index (from a baseline of 15.5±17.6 to 8.9±7.6 at follow-up) with a tongue retaining device that had an improved anterior socket for tongue suction. There have also been a few reports on the efficacy of, compliance with, and indications for a tongue stabilizing device [5–7], which is considered to be a type of tongue retaining device. In a pilot study, Kingshott et al. [5] first documented that a tongue stabilizing device reduced the severity of snoring and microarousals. Deane et al. [6] later demonstrated that a tongue stabilizing device was as efficacious as a mandibular repositioning splint in terms of reducing the apnea– hypopnea index (AHI), but noted that a lower compliance was observed with the tongue stabilizing device when both appliances were offered. After the Fukushima Daiichi Nuclear Power Plant accident that occurred right after the East Japan earthquake, Tsuiki et al. [7] proposed that a tongue stabilizing device could be a first-line treatment modality for snorers with suspected OSA at temporary refuges because of its simplicity. Although these reports describe certain favorable results with tongue retaining devices, strong evidence indicating the effectiveness of the device is still limited. Clinically, incomplete tongue suction often fails to hold the tongue, leading to unsatisfactory outcomes. Moreover, the tongue retaining device does not involve alternative methods when the suction pressure is incomplete. This may result in an overall lower effectiveness of tongue retaining devices [2] in comparison with mandibular repositioning splints. S. Tsuiki :K. Maeda :M. Kobayashi : T. Sasai :Y. Takahashi : Y. Inoue Neuropsychiatric Research Institute, Tokyo, Japan