Tmj, arthrocentesis complications?

Very rare!: Tmj arthrocentesis is a minor procedure with few risks or potential complications when properly performed. As with any procedure, infection and bleeding are risks. Those complications specific to TMJ arthrocentesis include: facial nerve damage with possible temporary weakness or paralysis of the forehead or upper eyelid muscles, and perforation of the ear canal with possible damage to the eardrum.

Swelling: As with all surgical procedures, there are always some potential complications. Although an arthrocentesis procedure is considered a minimally invasive procedure complications and include but are not limited to infection, bleeding, temporary change in occlusion, swelling, perception of "hearing while under water" and damage to nearby anatomic structures such as nerves, cartilage and bone.

Very few: Very few complications. Safe in the hands of an experienced doc. Worst thing is usually it doesnt work. May need arthroscopic surgery.