Mandibular Movement Analysis Offers Insight on Oral Appliance Efficacy in OSA

An analysis of mandibular movements provides valuable information on the effects of oral appliance therapy titration in patients with mild to moderate obstructive sleep apnea (OSA) once snoring is reported to be absent.

An intent-to-treat, prospective cohort study was conducted in a single sleep center at the University Hospital Namur in Namur, Belgium, during a period of 18 months in 2016 to 2017. Results of the analysis were published in CHEST.

Recognizing that the respiratory effort index derived from vertical mandibular movements (MM-REI) is a potential marker of increased respiratory effort during sleep, investigators sought to assess the effectiveness of mandibular advancement splint therapy using MM-REI compared with the apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) in patients with OSA. A total of 65 adult patients who were referred to the sleep center for loud snoring, with or without other symptoms suggestive of OSA, were invited to participate.

Overall, 56 individuals with OSA who had been treated with a custom mandibular advancement splint were assessed at the conclusion of the titration procedure, when snoring was reported as being absent by the participant’s sleep partner. The median age of the participants was 47 years. A magnetometer was used to capture all participants’ mandibular movements. The efficacy of mandibular advancement splint therapy was evaluated as the percent change from baseline.

At the conclusion of titration, all indices of OSA severity decreased in comparison with baseline values: AHI, –61.5% (95% CI, –48.9% to –71.1%) and ODI, –66.1% (–49.5% to –77.2%), with obstructive hypopnea index and MM-REI demonstrating the largest responses (–70.6% to –88.5% and –69.5% to –96.3%, respectively). MM-REI normalization because of decreases in both mandibular movement event rate and duration accurately reflected the appliance’s efficacy.

The investigators concluded that the decrease in vertical respiratory mandibular movements estimated by MM-REI and sleep respiratory effort duration accompanied the reduction in obstructive hypopneas, ODI, and AHI when snoring was resolved in participants with OSA who were treated with an optimally titrated mandibular advancement splint. When the respiratory disturbance index derived from MM was reduced by 75%, there is predicted decrease of 50% in both AHI and ODI.

Reference

Martinot J-B, Le-Dong NN, Crespeigne E, et al. Mandibular movement analysis to assess efficacy of oral appliance therapy in OSA [published online November 6, 2018]. CHEST.  doi:10.1016/j.chest.2018.08.1027