Interplay of Psychosocial, Clinical and Modulation Mechanisms in Chronic TMD-Related Disability.

BACKGROUND

Temporomandibular disorder (TMD) is a multifactorial condition characterised by pain and functional impairment in the orofacial region. Although psychosocial and psychophysical factors significantly influence chronic pain, their combined impact on functional disability remains poorly understood.

OBJECTIVES

To investigate the influence of clinical, psychosocial and psychophysical variables on functional disability related to chronic pain in muscular TMD, utilising principal component analysis (PCA) and logistic regression.

METHODS

A cross-sectional study with 77 women with painful TMD assessed clinical parameters (pain intensity, frequency, comorbidities and duration), psychosocial characteristics (stress, anxiety, depression, sleep quality and pain catastrophising) and psychophysical assessments (pressure pain threshold, mechanical pain threshold and conditioned pain modulation). PCA identified principal components, which were analysed using logistic regression to evaluate their association with chronic pain grades through the Graded Chronic Pain Scale.

RESULTS

Five principal components were identified: psychosocial, clinical pain, duration and extent of pain, pain modulation and sensory. The clinical pain component significantly predicted functional disability across all chronic pain grades (p < 0.05). The psychosocial component was a strong predictor of higher disability levels, whereas the pain modulation component showed a protective effect at the highest disability grade.

CONCLUSION

Functional disability in TMD is influenced by a complex interplay of clinical, psychosocial and psychophysical factors. Among five components founded, clinical pain and psychosocial components emerged as the most significant predictors of functional disability, with pain modulation providing a protective role at higher disability levels. This study elucidates the intricate interplay between clinical, psychosocial and psychophysical factors contributing to functional disability in chronic TMD-related pain.