Chewing ability as a parameter for evaluating the disability of patients with temporomandibular disorders

Restoration of chewing ability is an important aspect of the treatment for temporomandibular disorders (TMDs). However, too little attention has been paid to it. We have used a questionnaire to evaluate and score the chewing ability of TMD patients. The questionnaire includes 19 kinds of food and a chewing task. The patient was asked if she/he experiences difficulty in enjoying eating. The aim of this study was to evaluate correlations between score of chewing ability (SCA) and other symptoms/signs of TMD. Four hundred and seventy-three consecutive TMD patients were evaluated for SCA and other symptoms/signs including temporomandibular joint (TMJ) pain, TMJ and muscle tenderness, TMJ noise (clicking and crepitus), and maximum mouth opening. The relationship between SCA and other symptoms/signs were analysed by multiple regression analysis. Score of chewing ability correlated significantly with TMJ pain and mouth opening capacity but not with TMJ noise and muscle tenderness. Age was a background factor but sex was not. The result of this study suggests that SCA correlated with dysfunction of the TMD patients. This method could be used to evaluate the ability of chewing in assessment of TMD.