The aim of the study is to evaluate the clinical effectiveness of automated irrigation arthrocentesis in TMJ internal derangement compared to syringe-based lavage, which is limited by fluctuating hydraulic pressure and operator fatigue. This prospective clinical trial included 10 patients with clinically and radiographically diagnosed TMJ. Internal derangement unresponsive to >3 months of conservative therapy. Arthrocentesis was performed using Nitzan's two-needle technique with 150 ml of saline at 40 kpa via a dental implant motor. Pain, maximum mouth opening, lateral movement, and clicking were assessed preoperatively, immediately postoperatively, and at the 1st and 3rd months. Data were analysed using 100 Wilcoxon signed-rank tests (P < 0.05). All 10 patients completed follow-up. The Friedman test showed significant improvement across parameters over time (P < 0.001). Mean VAS scores decreased from 7.30 ± 0.95 preoperatively to 0.70 ± 0.95 at 3 months. Maximal mouth opening increased from 24.60 ± 1.43 mm pre-operatively to 39 ± 0.67 at 3 months. Maximal lateral movement showed a similar significant increase from 24.60 ± 1.43mm pre-operatively to 39.00 ± 0.66 at 3 months. Cochran's Q test showed significant reduction in clicking (Q = 13.957, P=0.003), decreasing from 8 patients pre-operatively to 1 patient at 3 months. The McNemar test was significant between preoperative and 3-month assessments only (P=0.016). Pressure-controlled Automated arthrocentesis is a safe, minimally invasive, cost-effective outpatient technique for TMJ internal derangement. Consistent lavage pressure improves functional recovery requiring specialized arthroscopic equipment. It may serve as a reliable intermediate option before open joint surgery.
