[Study on the influence of psychological factors in developing manifestations of temporomandibular disorders].

PURPOSE: To determine whether psychological factors be a risk of temporomandibular disorders (TMDs) or not. METHODS: A case-control study was carried out in 100 patients with TMD and 100 controls without TMD. A self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were used as the instruments to evaluate tendencies of anxiety and depression. The suspected confounding factors such as habit of eating hard food, chewing on one side, knocking teeth, night bruxism and history of extraction of teeth were also recorded. The data were analyzed by using Stata 11.0 software package to estimate risk strength of the psychological factors and confounding factors in occurrence of TMD. The cut point of significance was set up at 0.05. RESULTS: The mean scores of SAS and SDS of TMD group were significantly higher than those of control group (P<0.05).The trend tests of OR in SAS and SDS were both reaching to a significant level. The logistic analysis showed that only SAS and lateral chewing are significant risk factors of TMD (P<0.05). CONCLUSIONS: Tendencies of anxiety and depression are the significant risk factors related to TMD. However, when confounding factor such as chewing on one side exists, only tendency of anxiety remains a significant risk of TMD.