What has a year of social isolation due to the COVID-19 pandemic influenced oral parafunctional habits and temporomandibular disorders? A case-control study.

Objective: Few studies investigated the influence of oral parafunctional habits during the COVID-19 pandemic. Since some studies have demonstrated that signs and symptoms of temporomandibular disorder (TMD), as well as psychological alterations, increased during the COVID-19 pandemic lockdown, the aim of this study was to investigate whether social isolation is a situation that increases the prevalence of oral parafunctional habits.

Methods: This was an observational case-control study. An online survey with questions about TMD symptoms (Diagnostic Criteria Symptom Questionnaire) and oral parafunctional habits (Oral Behaviours Checklist [OBC]) was administered to Brazilian residents at two different times (2020 and 2021). The participants were divided according to social isolation practices into study groups (GI: 2020, n = 507; GIII: 2021, n = 282) and control groups (GII: 2020, n = 98; GIV: 2021, n = 202).

Result: In each group, we evaluated the association of the frequency of oral parafunctional habits with the symptoms of TMD, and we observed that individuals with a greater presence of painful TMD present a greater number of oral parafunctional habits. Despite the literature showing that individuals who practiced social isolation developed more oral parafunctional habits, when analysing the association of the OBC questions in Groups GI × GII and GIII × GIV, only 'sustained talking' (p = .0022) and 'hold telephone between your hand and shoulders' (p = .0124) showed a significant difference in GI × GII. Kendall's coefficient of concordance revealed that there was a very strong concordance (GI × GII 0.9515 (p = .0087) and GIII × GIV 0.9655 (p = .0074)) between the ranks of the analysed oral parafunctional habits in all groups.

Conclusion: We can state that Individuals who practiced social isolation did not present more oral parafunctional habits than individuals who did not.