Copyright © 2018 the Author(s). Published by Wolters Kluwer Health, Inc. We aimed to obtain greater understanding of dentists' distress when they diagnose and treat patients with temporomandibular disorders (TMD), and to explore ways in which TMD can be better treated. We conducted a cross-sectional study based on a questionnaire survey of dentists (n = 148). Dentists were queried using an open-ended questionnaire about distress they experienced when treating patients with TMD. Survey responses were analyzed using mixed methods. Associations between specific dentist and patient characteristics and types of distress were analyzed by one way analysis of variance and residual analysis. One hundred thirteen clinicians responded to the questionnaire, giving a 76% response rate. Thematic analysis identified 6 major themes: difficulty in predicting therapeutic effect and prognosis; difficulty in diagnosis; difficulty in the decision about whether to do occlusal adjustment; difficulty in specifying a cause; difficulty in communicating with patients and mental factors; and health insurance system barriers. Clinicians who reported difficulty in deciding whether to do occlusal adjustment saw significantly more patients who experienced shoulder stiffness and headache (P = .008 and P = .022, respectively). Dentists' knowledge of TMD guidelines was associated with a lower percentage of difficulty in predicting therapeutic effect and prognosis (residual analysis; P = .010). These findings provide important insights into clinician's perception of difficulties with patients experiencing TMD-related pain. Knowledge of the existence of TMD clinical practice guidelines may lower dentist distress, particularly with regard to prognosis. Further studies are needed to decrease dentist's distress and to overcome the evidence-practice gap in TMD treatment.