Differences in the effectiveness of stabilization splints between the categories of sleep bruxism

Purpose: The present study investigated the effects of stabilization splints on two categories of sleep bruxism using a portable electromyographic recording system. Methods: Twenty-six individuals confirmed as mild to severe bruxers by nocturnal masseter electromyographic episodes were enrolled in the study. Participants wore a stabilization splint during sleep for 30 nights, and mas-seter muscle activity was measured at baseline, immediately after, and 1 and 4 weeks after insertion of the splint. Bursts in masseter electromyographic episodes were separated into phasic bursts or tonic bursts, then each burst was analyzed in terms of duration, frequency, and magnitude of bursts. Results: The frequency of phasic bursts significantly decreased immediately after insertion of the splint compared with the baseline. The geometric mean magnitude of tonic bursts decreased when wearing the splint compared with the baseline. Conclusion: These findings suggest that stabilization splints reduce jaw-muscle activity during sleep in patients suffering from sleep bruxism by reducing the frequency of phasic bursts in the short term and reducing the magnitude of tonic bursts over a longer period.