Inferior Jonit Space Injection Therapy in Patients with TMD

Aims: To compare the outcome of inferior joint space and superior joint space injection of sodium hyaluronate in patients with anterior disc displacement without reduction of the temporomandibular joint (TMJ). Methods: 120 patients were randomized to two groups, one group receiving superior joint space injections of sodium hyaluronate and the other receiving inferior joint space injections of sodium hyaluronate. To evaluate the efficacy of both procedures based on the diagnosis of clinical signs and symptoms of anterior disc displacement without reduction in the 3 and 6 months follow-up after the last of the three injection therapies by maximal mouth opening (MMO), pain intensity on a visual analogue scale(VAS), and modified Helkimo's clinical dysfunction index . Results: In the superior joint space therapy, 50 patients follow up for 3 months and 6 months and in the inferior joint space therapy, 54 patients follow up for 3 months and 6 months. MMO, VAS and Helkimo's index improved in both the superior joint space therapy and the inferior joint space therapy at 3 months and 6 months follow up. There was a significant reduction in TMJ pain in the inferior joint injection group at 3 months follow-up as compare to the superior joint injection group (p<0.001), but the results of increasing MMO and TMJ function was almost the same in both groups at 3 months follow-up. There was a significant difference between the inferior joint injection group and superior joint injection group in MMO (p<0.005), VAS (p<0.001) and Helkimo's index (p<0.001) at 6 months follow-up. Conclusion: This study demonstrated that the inferior joint space injection with sodium hyaluronate is a valid method of treating the anterior disc displacement without reduction of TMJ.