TMDs tied to depression, somatization

There is a high prevalence of psychological disorders in patients with temporomandibular disorders (TMDs), according to an article published on September 13 in the Journal of Prosthetic Dentistry. The study focused on depression or somatization, a disorder in which symptoms have no identifiable cause.

TMDs affect the muscles involved with chewing, the temporomandibular joint, and other associated structures. These disorders are commonly the main cause of pain in the orofacial region and may eventually cause psychological problems in patients, but the burden of psychological disorders is unknown.

To conduct this study, researchers searched for clinical observational studies investigating depression and somatization in patients with TMD diagnosed by the Diagnostic Research for Temporomandibular Disorders criteria in muscular, articular, and disc disorders. A total of 22 articles were included in the study.

The general prevalence of depression and somatization in patients diagnosed with TMD was estimated at 43% and 60%, respectively. The average overall score for depression was estimated at 0.92, which is classified as moderate depression in the scale used by researchers. The average overall score for somatization was estimated at 1.09, which is classified as severe somatization according to the scale.

"The research determined that a large portion of patients with a TMD diagnosis treated at a TMD service have some degree of somatization," wrote the study authors, led by Gabriella Caovilla Felin of the University of Passo Fundo in Brazil (J Prosthet Dent, September 13, 2022).

Furthermore, a muscle disorder was most often diagnosed among patients with TMD, followed by the association of muscle disorder with another diagnosis. This finding is consistent with a previous study that found muscle pain was the most frequent cause of orofacial pain, followed by reduced disc displacement and arthralgia.

"Patients with more than a single TMD diagnosis, of chronic character, with high levels of pain-related disability had significantly higher scores for depression, pain intensity, somatization, and mandibular disability than patients with low levels of disability related to pain," wrote the study's authors.

Depression and somatization are considered risk factors for TMDs, and these two psychological conditions can worsen the symptoms and perpetuation of TMD.

"Psychological disorders must be analyzed when managing orofacial pain since pain has a psychological and social component as well as a biological element," Felin and colleagues explained.

Muscle hyperactivity related to stress and oral health habits have been suggested as etiological factors in addition to a psychological factor that exacerbates symptoms and prevents patients from seeking treatment. Further, psychological conditions have explained why some patients do not respond to conventional therapies.

Based on this study's findings, patients with TMD should be screened for depression and somatizations.

"When managing patients with TMDs in clinical practice, psychological factors should be evaluated since they may be the main risk factor for triggering or perpetuating TMDs," Felin and colleagues concluded.