Temporomandibular joint disorders are a heterogeneous group of diseases that cause progressive joint degeneration leading to chronic pain and reduced quality of life. Both effective pain reduction and restoration of TMJ function remain a challenge. Internal derangement (ID) of the temporomandibular joint (TMJ) is one of the most common forms of temporomandibular disorders .TMJ arthrocenthesis developed from the great success of TMJ arthroscopic lysis and lavage, as well as pumping irrigation of the upper joint space, in treating patients with temporomandibular closed lock.To enhance the outcome of arthrocenthesis, post operative intra-articular injection of various substances were used regarding their analgesic, anti-inflammatory and lubrication properties. Local anesthetics, morphine, corticosteroids, sodium hyaluronate, tenoxicam, celecoxib and pixroxicam were introduced as treatment modalities.The presented study was concerned with the treatment of patients with internal derangement of the temporomandibular joint by arthrocenthesis with normal saline, and corticosteroids and hyaluronic acid as an intra-articular drug injection.The study was conducted on 12 female patients that were randomly selected from the outpatient clinic of the Oral and Maxillofacial Surgery Department, Faculty of Oral and Dental Medicine, Cairo University. The selected patients were asked to go through a full clinical history and examination that was documented in a specific chart. The patients were divided randomly into two groups:Group A: (Study Group)Consisted of six patients treated using a combination of Hyaluronic Acid and Corticosteroid following TMJ arthrocenthesis.Group B: (Control Group)Consisted of six patients treated using corticosteroid alone following TMJ arthrocenthesis.All patients were recalled for follow up on a fixed recall system as follows:Follow up 2 weeks from the second visit, and were evaluated in the intervals of 2,4,6,8 and 12 weeks.The results of the study concluded the following:•Single needle arthrocenthesis is an effective technique for treatment of internal derangement of the TMJ.•The mix of hyaluronic acid and corticosteroid did not show any significant difference when compared to the injection of corticosteroids alone in mouth opening and VAS score.•Psychological stresses have a negative effect on temporomandibular condition, and the effectiveness of the treatment procedure.