ObjectivesTo assess the association between waking‐state oral behaviours and temporomandibular disorder (TMD) subgroups and to develop new scoring methods for the Oral Behavior Checklist (OBC).MethodsPatients with any TMD diagnosis, according to the diagnostic criteria for TMD (DC/TMD), were divided into subgroups: ‘Dysfunctional‐TMD’ (n = 70), only mechanical dysfunction; ‘Painful‐TMD’ (n = 204), only myalgia, arthralgia or both; and ‘Painful‐Dysfunctional TMD’ (n = 95), combined pain and dysfunction. A group of individuals without TMD, ‘Non‐TMD’ (n = 374), was used for testing associations. Participants completed the OBC. An exploratory factor analysis, followed by a confirmatory factor analysis of the OBC responses, identified 2 major factors, named non‐functional activities (NFA) and functional activities (FA). Component total scores were computed. Differences among subgroups for OBC‐MS (mean score) and NFA and FA factor scores were estimated using one‐way ANOVA and Tukey post hoc tests. Significance was set at p < .05.ResultsThe OBC‐MS in Non‐TMD, Painful‐TMD and Painful‐Dysfunctional TMD subgroups was higher than in the Dysfunctional‐TMD subgroup (p ≤ .001). NFA in Painful‐TMD and Painful‐Dysfunctional TMD subgroups were higher than in the Non‐TMD group (p < .05); NFA in the Dysfunctional‐TMD subgroup were lower than in the Painful‐TMD subgroup (p = .034). In contrast, FA in Painful‐TMD, Dysfunctional‐TMD and Painful‐Dysfunctional TMD subgroups were lower than in the Non‐TMD group (p < .0001).ConclusionsA new scoring method for the OBC results in item reduction and creation of meaningful subscales for functional and non‐functional behaviours, which are differentially associated with painful and dysfunctional TMDs. This may help clinicians to better tailor treatment for the management of subtypes of TMD patients.