Ultrasound Guided Versus Conventional Arthrocentesis in Treatment of Temporomandibular Joint Internal Derangement.

* Scrubbing and draping of the patient will be carried out in a standard fashion using betadine surgical scrub. * Head turned to the affected side. • External auditory meatus will be blocked with a cotton plug. * Transducer is placed over TMJ, parallel to the long axis of mandibular ramus. • Transducer is tilted until the optimal visualization is obtained. * Disc is visualized as a thin homogenous, hypo-to-iso-echoic band lying adjacent to the inferior relation. The bony landmarks of the mandibular condyle and the articular eminence are visualized as hyperdense lines. * Superior joint space located between the disc and articular eminence is the targeted point of the needle. Intra-operative procedures - continued in both groups: * Lavage is performed with 100 ml of saline solution. * 1 ml of Hyaluronic acid is injected into the superior joint space. * Puncture point is covered with sterile dressing for 24 hours

* Scrubbing and draping of the patient will be carried out in a standard fashion using betadine surgical scrub. * Head turned to the affected side. • External auditory meatus will be blocked with a cotton plug. * A line will be drawn from tragus of the ear to the outer canthus of the eye with ink. * Double needled canula is inserted into superior compartment of the joint space 2mm below and 10 mm ahead of mid-tragal end of Holmund Hellsing's line. Intra-operative procedures - continued in both groups: * Lavage is performed with 100 ml of saline solution. * 1 ml of Hyaluronic acid is injected into the superior joint space. * Puncture point is covered with sterile dressing for 24 hours