Abstract This study aimed to evaluate the effectiveness of a new combined treatment approach using arthrocentesis, hyaluronic acid (HA) injection, mandibular manipulation (MM), and the Twin-Block appliance (TBA) for managing acute anterior disc displacement without reduction (ADDwoR). A retrospective cross-sectional study was designed. Thirty-seven patients (38 joints) diagnosed with acute ADDwoR were treated with arthrocentesis plus HA combined with MM and TBA in turn from January 2022 to December 2023. The maximum mouth opening (MMO), visual analogue scale (VAS) pain score, condyle/disc position were measured and comparatively analyzed at baseline and one week, three and six months post-treatment. Analysis of variance, Dunnett’s T3 analysis, and paired samples t-tests were conducted for statistical analyses setting the threshold for statistical significance at P