Complex temporal patterns of bruxism require multi-day observation to capture clinically meaningful patterns, with three days being the minimum viable EMG monitoring period for comprehensive bruxism assessment.
Sleep grinding episodes showed a progressive day-to-day increase across measurement nights.
Sleep clenching episodes demonstrated both a day-to-day increase and a linear decline across sleep hours within each night.
Awake grinding episodes showed an hourly decline throughout waking hours with no significant day-to-day variation.
Awake clenching episodes exhibited curvilinear (polynomial) patterns for both hourly and daily variations.
The four bruxism behavior types (sleep grinding, sleep clenching, awake grinding, awake clenching) displayed distinct temporal signatures from one another.
Three days was identified as the minimum viable EMG monitoring period for comprehensive bruxism assessment.
The study employed a mixed model analysis framework to evaluate both hourly and day-to-day variations in bruxism episodes.
This research suggests that teeth grinding and clenching — collectively known as bruxism — follow complex and distinct patterns depending on whether they occur during sleep or while awake, and whether the behavior is grinding (back-and-forth jaw movement) versus clenching (sustained jaw pressure). Using small wearable muscle activity sensors worn continuously for three days and nights by 20 participants, researchers found that nighttime grinding tended to get worse each successive night, while nighttime clenching was highest early in the sleep period and tapered off. Daytime grinding, by contrast, was highest in the morning and decreased as the day went on, while daytime clenching followed a more complex wave-like pattern both within each day and across the three days. A particularly important practical implication is that recording bruxism for only a single day or night may paint a misleading picture. Because each type of bruxism behavior follows its own unique time course that unfolds over multiple days, a snapshot from just one recording session could miss the true severity or variability of the problem. The researchers suggest that three days is likely the minimum monitoring period needed to get a clinically useful picture of a person's bruxism. This research also highlights that sleep bruxism and awake bruxism should not be treated as a single condition when it comes to measurement and monitoring. Their different temporal patterns suggest they may have different underlying mechanisms and may need to be tracked separately. The authors call for standardization in how bruxism is measured using portable devices — including which specific measurements are used and how long recordings should last — so that future research and clinical assessments can be more consistent and comparable.
Alona E, Amit S, Khalil M, Ilana E. (2026). Temporal patterns of bruxism behaviors: multiple day recording with portable electromyography.. Scientific reports. https://doi.org/10.1038/s41598-025-30704-z