Role of Genetic Component in Temporomandibular Disorders: A Review

The role of genetics in Temporomandibular joint (TMJ) has been a topic of interest recently. Any impairment of the TMJ can result in Temporomandibular joint disorders (TMDs), characterized by pain, restriction of jaw movement, and other associated symptoms. Genetic variables are thought to play a role in aetiology of TMDs and the morphological and functional differences observed in the TMJ. Numerous studies have identified particular genes and genetic variations in the onset of TMD. These genes are involved in biological functions, including inflammation, pain perception, cartilage metabolism, and collagen formation. TMD risk has been linked to genetic polymorphisms in collagen genes, including COL1A1 and COL5A1. The structure and integrity of the TMJ could change causing fragility of collagen. Another essential step for the health of the TMJ is cartilage metabolism. Genetic differences in genes encoding cartilage metabolism-related enzymes like MMP-3 and TIMP-2 have been associated with TMDs. These disparities disturb the balance of cartilage degeneration and regeneration and lead to cartilage damage. Important aspects of TMDs include the impression of and sensitivity to pain. Changes in pain perception and higher vulnerability to TMDs have been linked to genetic differences in pain-modulating genes such COMT and OPRM1. These changes may have an impact on how the central nervous system processes pain signals causing orofacial pain. This knowledge may also aid in the future development of targeted medicines and individualised treatment plans.