Abstract: The present invention discloses a mechanical device for joint distraction of the Temporomandibular Joint (TMJ) comprising an upper arm (19) and lower arm (20) joined in a pivotal zone by a mechanical and pivoting component (5) and by a spring (6) or mechanical component between the arms (19) (20). Each arm has a handle (1) of the upper arm (19) and a handle (4) of the lower arm (20). Each arm has an intraoral mouth end for contact with dental surfaces: the upper arm (19) has a tray (2) with a flat support surface for the maxillary teeth flanked by a containment flap (11) of the upper tray; the lower arm (20) has a curvature until its end, with a customized surface (3) for supporting the lower teeth. It presents a mechanical component (13) that limits the extent of movement and force applied by the patient or clinician.