BackgroundThe relation between personality, psychosocial factors, somatisation, andoral behaviours as risk factors to temporomandibular disorder symptoms have notbeen well established.ObjectivesThis study examined the association of temporomandibular disorder (TMD) symptoms with personality traits, psychological distress, somatisation and oral behaviours. The psychosocial and oral behavioural risk factors for TMD symptoms were also established in Asian young adults.MethodsParticipants were recruited from a large private University. Based on the quintessential five TMD symptoms (5Ts) of the DC/TMD, the participants were stratified into those with no (NT), painful (PT), dysfunctional (DT) and mixed (MT) TMD symptoms. Personality traits, psychological distress, somatisation and oral behaviours were evaluated with the Big Five Inventory‐10 (BFI‐10), Depression, Anxiety, Stress Scales‐21 (DASS‐21), Patient Health Questionnaire‐15 (PHQ‐15) and Oral Behaviours Checklist (OBC) accordingly. Data were examined using Kruskal–Wallis/Mann–Whitney U and Chi‐squared tests, as well as multivariate logistic regression analysis (α = .05).ResultsOf the 420 young adults (mean age 22.7 ± 1.1 years) evaluated, 41.4% had no TMD symptoms, while 17.4%, 20.0% and 21.2% reported PT, DT and MT, respectively. Though personality traits did not vary notably, participants with MT and PT had significantly higher levels of negative affectivity, anxiety and stress than the NT group. Moreover, those with MT and PT presented significantly greater somatisation and more oral behaviours than the DT and NT groups. Multivariate regression analyses indicated that anxiety, somatisation, sleep‐related and waking‐state nonfunctional oral activities were associated with painful and/or dysfunctional TMD symptoms.ConclusionsExcept for sleep‐related oral activity, psychosocial and oral behavioural risk factors differed for painful, dysfunctional and mixed TMD symptoms in Asian young adults.