P095 Temporalis and Masseter EMG leads in the assessment of Sleep Bruxism scoring in individuals with Obstructive Sleep Apnea and Sleep Bruxism

Abstract Study Objectives Sleep bruxism (SB) is defined as the repetitive jaw muscle activity characterized by the clenching or grinding of teeth. Untreated SB may lead to dental complications, orofacial pain, OSA and insomnia. We postulate that SB scoring is more accurate with the addition of bilateral masseter and temporalis EMG leads (SB leads) to conventional PSG. Methods Full-night PSG of 25 individuals with OSA and history of SB were included. An independent sleep technologist (RPSGT) scored bruxism episodes according to the AASM criteria. The Bruxism Episode Index (BEI) measures the number of bruxism episodes per hour of sleep (<2: irrelevant SB; 2–4: mild/moderate SB; >4: severe SB.) SB-related EMG jaw muscle activity recorded are Rhythmic Masticatory Muscle Activity episodes and bursts (RMMA), which were scored using SB leads in addition to conventional PSG leads. Masseter and temporal EMG bursts with duration >0.25sec were selected according to published criteria. RMMA is categorized as phasic (≥3 rhythmic bursts 0.25-2sec) or tonic (sustained burst lasting >2sec). The same PSG were re-scored without these additional SB leads and the results were compared. Results Of the 25 PSGs without SB leads, incidence of none, mild to moderate and severe SB is 7, 11 and 7. With addition of the SB leads, incidence of none, mild to moderate and severe SB is 2, 5 and 18. Median Bruxism Episode Index (BEI) was 6.4 and 2.8 with and without SB leads respectively. Conclusions Conventional PSG without SB leads results in significant underestimation of SB incidence and severity.