The purpose of this study was to compare the clinical success and efficacy of single-needle, double-cannula arthrocentesis with conventional arthrocentesis techniques in patients with temporomandibular joint disorders. Patients with nonreducible disc displacement complained of limited mouth opening and/or pain. All treated patients had baseline and follow-up (with mouth opening and VAS). Comparisons were made within and between groups.

The patients included in the study were evaluated in the preoperative, 1week, 1-3, and 6 months after the procedure. Double-needle group: two needles were inserted into the joint and washed. In the single-needle group, two needles were bent (from their lower parts) before the procedure and their pointed ends were joined by placing acrylic on the plastic parts from a single point. The resulting combined needle was directed to the upper joint space and washed. 13 underwent single-needle double cannula arthrocentesis and 15 underwent double needle arthrocentesis.

Inclusion Criteria:

• with complaints of pain and restricted mouth opening and who had not received any previous treatment.
• Patients with a diagnosis of disc displacement without reduction characterized by persistent or frequent TMJ pain, history of joint clicking, limited mouth opening with deviation to the affected side, limited lateral movement to the opposite side, limited protrusive movements with deviation to the affected side were included.

Exclusion Criteria:

• Patients with systemic inflammatory joint disease, facial growth disorder, and direct trauma to the TMJ were excluded.