Temporomandibular Joint (TMJ) and Muscles of Mastication

When radiation portals include the temporomandibular joint or masticatory muscles, cellular damage and subsequent tissue fibrosis may compromise the integrity of the joint capsule or musculature. These effects, which typically appear 3 to 6 months post-radiotherapy, may cause muscle spasms, trismus, and restricted function, with threshold doses ranging between 15 Gy and 50 Gy.¹³