Technique for achieving a stable position of the condylar process during injection into the temporomandibular joint.

Our purpose was to develop a reproducible and easy-to-use technique to establish the best place to inject the temporomandibular joint (TMJ) that ensured stable positioning of the condylar process. We implemented a 3-dimensional process to treat osteoarthritis of the TMJ with hyaluronic acid that was guided by cone-beam computed tomography (CT), and stabilised with a maxillomandibular wax bite block. Two wax rims (fabricated from previously-taken impressions) were attached together securely to stabilise the condyles during imaging and to fix the maxillomandibular position. The use of 3-dimensional cone-beam CT increased the accuracy of the injection. The point, angle, and depth were ascertained precisely, which was intended to ensure safety and give the physician confidence, even when treating patients with anatomical anomalies. The procedure had good stability (the displacing effect of muscle contraction was eliminated) and it presented an easy and reproducible 3-dimensional method for injecting the TMJ that was safer than the conventional one.