Treatment outcome of the two-part semi-rigid oral appliance in obstructive sleep apnea

AimThe aim of this study was to assess the effectiveness of the two-part semi-rigid oral appliance, Silensor® (Erkodent, Tuttlingen, Germany) which prevents the mandible from retracting during mouth opening.Materials and methodsTen patients with mild or moderate obstructive sleep apnea (2 males and 8 females; mean age = 62.5 ± 10.0 years) were recruited and lateral cephalometric radiographs were taken. The patients underwent polysomnography before and after 3 months of receiving treatment with the Silensor®. The relationship between the improvement in the polysomnographic variables after the therapy and the cephalometric features was analyzed.ResultsA significant difference was observed in the apnea–hypopnea index after 3 months of Silensor® therapy (1st (baseline), 17.1 ± 5.5; 2nd (therapy of Silensor®), 11.0 ± 7.2, p = 0.011). Furthermore there was a significant positive correlation between the improvement in the degree of slow wave sleep (%) and the mandibular plane angle (R = 0.662, p = 0.037), as well as between the improvement in degree of slow wave sleep (%) and the lower face height (R = 0.845, p = 0.002). A significant negative correlation was observed between the improvement in degree of sleep efficiency (%) and the soft palate area (R = −0.809, p = 0.005).ConclusionThese results suggested that keeping the nasopharyngeal airway space during mouth opening improves apnea–hypopnea index of some patients with mild or moderate obstructive sleep apnea and quality of sleep in obstructive sleep apnea patients with a long lower face height and a small soft palate.

▸ There is no information as to which OSA patients may be expected to benefit from the two-part semi-rigid OA, Silensor®. ▸ We analyzed changes in the PSG variables after the therapy and the cephalometric features of ten OSA patients. ▸ The mean AHI was improved after 3 months of Silensor® therapy. ▸ Significant correlations were observed between the improvement of slow wave sleep (%) and some cephalometric variables. ▸ Keeping the nasopharyngeal airway space during mouth opening improves AHI and quality of sleep of some OSA patients.