Traumatic TMJ dislocation is uncommon in the paediatric population, and long-standing bilateral cases are particularly rare. Early recognition and appropriate management are essential to prevent functional impairment and growth disturbances.

A 4-year-old female child presented with a sustained inability to close her mouth following a fall. Clinical examination and radiographic evaluation confirmed bilateral TMJ dislocation. Multiple attempts at manual reduction were unsuccessful, necessitating open reduction. The procedure was performed via a preauricular approach with meticulous preservation of the capsular and periarticular tissues to minimise the risk of future growth-related disturbances.

Postoperative recovery was uneventful, with restoration of normal mandibular function and stable joint position on latest four month follow-up. This case underscores the diagnostic challenges associated with long-standing TMJ dislocation in children and highlights open reduction as a viable option when conservative techniques fail, particularly when preservation of developing joint structures is paramount.