Search

The pathogenesis, pathophysiology, and pharmacotherapy of sleep bruxism (SB) are still not fully understood. We investigated symptomatology, objective and subjective sleep and awakening quality of middle-aged bruxers compared with controls and acute effects of clonazepam 1 mg compared with placebo by polysomnography and psychometry. Twenty-one drug-free bruxers spent 3 nights in the sleep lab, 21 age- and sex-matched controls 2 nights. Clinically, bruxers exhibited deteriorated PSQI, SAS, SDS and IRLSSG measures, polysomnographically impaired sleep maintenance, increased movement time, stage shift index, periodic leg movements (PLM) and arousals and psychometrically deteriorated subjective sleep and awakening quality, evening/morning well-being, drive, mood, drowsiness, attention variability, memory, and fine motor activity. As compared with placebo, clonazepam significantly decreased the SB index in all patients (mean: -42 +/- 15%). Sleep efficiency, maintenance, latency, awakenings and nocturnal wake time, the stage shift index, S1, PLM, the arousal index, subjective sleep and awakening quality, and fine motor activity improved.

Objectives: Sleep bruxism (SB) is a parasomnia defined as a stereotyped movement disorder characterized by grinding or clenching of the teeth during sleep. Pathophysiologically, SB is the result of biological and psychosocial influences. Treatment comprises behavioral, orthodontic and pharmacological interventions. While benzodiazepines and muscle relaxants have been reported by clinicians to reduce bruxism-related motor activity, placebo-controlled studies are lacking. Thus, the aim of the present study was to investigate the acute effects of clonazepam (Rivotril) as compared with placebo, utilizing polysomnography and psychometry., Method: Ten drug-free outpatients (6 females, 4 males), aged 46.5 +/- 13.1 years, suffering from SB (ICD-10: F45.8; ICSD: 306.8) and having been treated by bite splints were included in the trial. Comorbidity was high: 7 patients presented nonorganic insomnia related to adjustment or anxiety disorders (5 patients) or depression (2 patients); all patients had a concomitant movement disorder (6 restless legs syndrome, 4 periodic leg movement disorder). After one adaptation night, patients received placebo and 1 mg clonazepam 1/2 hour before lights out in a single-blind, nonrandomized study design. Objective sleep quality was determined by polysomnography, subjective sleep and awakening quality by rating scales, objective awakening quality by psychometric tests. Clinical evaluation was based on the Pittsburgh Sleep Quality Index (PSQI), the Zung Depression (SDS) and Anxiety (SAS) Scales, the Quality of Life Index, the Epworth Sleepiness Scale and the International Restless Legs Syndrome Study Group (IRLSSG) Scale., Results: On admission, SB patients exhibited deteriorated PSQI, SAS, SDS and IRLSSG measures. As compared with placebo, 1 mg clonazepam significantly improved the mean bruxism index from 9.3 to 6.3/h of sleep. Furthermore, it significantly improved the total sleep period, total sleep time, sleep efficiency, sleep latency and time awake during the total sleep period, and increased stage 2 sleep and movement time. Periodic leg movements decreased significantly, while the apnea index and apnea-hypopnea index increased marginally, but remained within normal limits. Subjective sleep quality improved as well, while in mood, performance and psychophysiology no changes were observed., Conclusion: Acute clonazepam therapy significantly improved not only the bruxism index but also objective and subjective sleep quality, with unchanged mood, performance and psychophysiological measures upon awakening, suggesting good tolerability of the drug., (Copyright (c) 2005 S. Karger AG, Basel.)