Daylight Saving Time and Self-Reported Bruxism Manifestations: First Results From a Multicentric, Case-Control Study

Introduction:A circadian profile has been suggested in bruxism that may characterize sleep/awake recurrent masticatory muscle activity fluctuations.The current study aims to test whether daylight saving time (DST) as a disruptive factor to the physiologic circadian rhythmicity may affect self-perceived bruxism manifestations.Methods: Patients with the criteria for probable bruxism (either awake bruxism or sleep bruxism) were collected from specialized centers in Portugal, Spain, and Brazil.Bruxism symptoms/intensity changes from pre-DST to post-DST implementation were assessed by a questionnaire applied during the week following implementation of DST.Case and control groups (no DST implemented in the country) were compared, and relative frequency of patients reporting changes was computed, and then analyzed using standard statistical approaches.Results: A total of 48 patients were included.Circadian distribution of bruxism manifestations varied across the cohort in a symmetric way in cases and control groups.A total of 54.1% of patients and only 18,2% of control patients complained about worsened bruxism symptoms during the week corresponding to the switch to DST (P<0.05).Any of the patients among the cases and 63.6% among the control group reported an improvement of bruxism symptoms after DST/sham treatment.Discussion: Preliminary findings are suggestive that bruxism-related symptoms may be affected by the switch to DST, supporting the hypothesis of a sleep-independent circadian role in this condition.Clinical relevance of such findings warrants further confirmation and exploration in future studies.