The temporomandibular joint has synovial fluid which allows the disc to move freely as the jaw moves. If the disc is displaced or is not moving correctly, the synovial fluid within the joint becomes more viscous. Over time, this causes the disc to be stuck causing the jaw to lock.
Arthrocentesis is a technique that washes out the affected synovial fluid and is replaced with sterile saline. Within a very short period of time, the joint space is replaced by new synovial fluid which allows the disc to have greater mobility. A steroid is also injected into the joint space to decrease any inflammation that usually occurs when the disc is displaced.
The procedure is usually performed in the office either under local anesthesia or light IV sedation. The patient is instructed to wear their bite guard immediately after the procedure and to eat soft food for a few days. There is usually minimal if any postoperative discomfort.