Sleeping in a hunched position known as the Fowler position and taking medications prescribed for glaucoma may reduce nocturnal bruxism.
Episodes of sleep bruxism (SB) and rhythmic masticatory muscle activity (RMMA) may have decreased due to decreased intracranial pressure (ICP). ICP is a determinant of sympathetic nervous system activity and is associated with teeth grinding when SB and RMMA increase, the authors write.
“Changes in ICP and sympathetic activity induced by Fowler's position and methazolamide may contribute to the reduction in RMMA/SB episodes,” write the authors, led by Dongyuan Yao of Jiangxi Provincial People's Hospital in China.
SB has been reported in approximately 8% of adults and up to 17% of children and adolescents. According to the study, nighttime grinding and clenching of teeth is associated with many factors, including lifestyle habits such as smoking and drinking coffee, as well as stress, anxiety and genetics, and can cause jaw pain and tooth damage.
Metazolamide has been tested as an intracranial pressure lowering agent because previous studies have demonstrated its benefit in the treatment of idiopathic intracranial hypertension.
To examine the effects of the Fowler position during sleep and methazolamide treatment on the occurrence of teeth grinding episodes, a randomized controlled trial was conducted involving 20 patients aged 18 to 27 years suffering from nocturnal bruxism. Of these patients, 11 slept in the Fowler position or supine, i.e. at an angle of 15° to 30°. Nine participants took 100 mg of methazolamide or placebo three to four hours before bedtime. The authors write that the patients underwent polysomnographic studies.
The authors reported that the SB index, the number of masticatory muscle electromyographic impulses per hour of sleep, the ratio of RMMA duration to total sleep duration, the total limb movement index, the RMMA limb movement index, and the number of SB clusters per hour of sleep were significantly less (p < 0 .05-0.001) in the Fowler's position and after taking methazolamide.
During stage 2 non-rapid eye movement sleep, low-frequency heart rate variability was significantly lower (p < 0.05) in those sleeping in the Fowler position and in those taking methazolamide.
However, the study was not without limitations. The sample size was small and the age range of patients was limited.
The authors write that more studies involving noninvasive recording of ICP in patients with SB should be conducted in the future.
“In patients with SB without concomitant OSA, Fowler's position and methazolamide treatment resulted in a significant reduction in the occurrence of RMMA/SB episodes without significant changes in sleep patterns and performance,” Yao concluded.