The Effect of Clear Aligners on Awareness of Tooth Clenching.

Introduction: Clear aligners (CAs) are an increasingly popular treatment option in modern dentistry, yet surprisingly little is known about their potential unwanted side effects. Previous observations suggest that CAs may induce tooth clenching, which, in turn, could lead to masticatory muscle discomfort or pain. Nevertheless, available information is mainly subjective, anecdotal, and contradictory. The aim of this study was to investigate the effect of wearing passive CAs on both objectively measured tooth clenching and the awareness of tooth clenching during stress-inducing tasks.

Methods: Twenty-one study participants completed a 10-min stress-inducing mental arithmetic task, both with and without the passive CAs in place. During these tasks, masticatory muscle activity (MMA) was continuously recorded to objectively assess clenching. Following completion of each task, participants rated their perceived clenching and stress using visual-analogue scales. After the final task, they completed the Oral Behaviours and Somatization Questionnaire. Spearman's correlation and mixed models were used for the statistical analyses.

Results: Wearing CAs did not significantly affect MMA or perceived clenching. MMA was not associated with self-reported oral behaviours, but a significant association was found with somatisation scores (p < 0.05). Individuals with higher somatisation scores experienced more MMA contraction episodes compared to those with lower scores (R = 0.47; p = 0.015).

Conclusions: Wearing an aligner does not influence either perceived or objectively assessed clenching over the short term. Self-reported clenching is not a reliable measure of actual clenching behaviours. Somatisation appears to be a key mediator in the relationship between clenching and clear aligner wear.