Sleep bruxism can be a harbinger of sleep disordered breathing

Background & Objective: The mechanism of sleep bruxism (SB) remains an enigma to this day. The saga of SB was kept alive by dental surgeon's relentless research. Then the sleep physicians stepped in with their polysomnogram (PSG), having a hunch that the answer was in sleep disordered breathing (SDB). In the face of uncertainty and conflicting reports in the relationship between SDB and SDB that followed, we made an alternative approach to investigate the pathogenesis of SB, using CPAP as an experimental tool. The objective was to substantiate that SB can occur during the arousal phase of SDB. Methods: This is a PSG study of SB in 20 consecutive cases of SDB. First night PSG was diagnostic and followed by the second night PSG for Continuous Positive Airway Pressure (CPAP) titration for treatment. We studied every SDB wave and observed its relationship with arousal and SB. An experiment was conducted on the second night, where we used CPAP as a tool, to stent upper airway and toggle the pressure to cause apnea and await the aftermath. Results: Diagnostic PSG of all 20 patients showed a common sequence of events: SDB is followed by brain arousal which is followed by SB, there being an almost one to one relationship between SB and SDB. On the second night's PSG, toggling CRAP down or up causes SDB to come on or off, respectively. SB followed suit along with arousal. Conclusion: SB commonly occurs during arousal from SDB. CPAP gets rid of SDB and SB.