This randomized controlled clinical trial aims to compare the clinical and magnetic resonance imaging (MRI) outcomes of three intra-articular injection protocols for the treatment of temporomandibular joint (TMJ) internal derangement with reduction. Sixty patients who remain symptomatic despite conservative therapy will be randomly assigned to receive hyaluronic acid combined with platelet-rich plasma (PRP), tenoxicam, or corticosteroid. Clinical outcomes including pain intensity, maximum mouth opening, and joint clicking, together with MRI findings, will be evaluated over a 6-month follow-up period.