The aim of the study was to compare the presence of oral tori and parafunctional activity (clenching, grinding teeth and/or bruxism) between temporomandibular disorder (TMD) patients and control subjects. Fifty-nine TMD and 353 control subjects were included. The groups were similar in sex and age distribution. There was no significant difference in prevalence of torus palatinus (TP) between TMD and control group (P = 0.2), while torus mandibularis (TM) was more common in TMD than in control group (P < 0.0005). Parafunctional habit was more common in TMD patients than in the control group (P < 0.0005). There was no significant association between size of TM and Helkimo's dysfunction index (P = 0.4). The results show that the prevalence of TM and parafunctional activity was higher in TMD than control patients. TM might be useful as an indicator of increased risk of TMD in some patients.