The invention relates to a customised intraoral jaw distractor, of the type that comprises at least two anchoring means (1, 2) attached to the mandibular body at two fixed anchor points, located on either side of the osseous callus. Such a distractor is characterised in that it includes: a) a threaded cylindrical rail (6) connecting the two anchoring means (1, 2) b) a mobile carriage (10) guided to slide on the rail (6) and attached to the osseous segment to be distracted, said mobile carriage being provided with a worm screw (11) with a thread that complements that of the rail and engages with the latter c) a pin (12) secured to the worm screw (11) and controlling the rotation thereof, said pin, which is parallel to the rail (6), being supported by two bearings (13, 14) arranged on the mobile carriage (10), on either side of the worm screw d) at least one resilient part (15) which said pin (12) passes through and which engages with one end (16) of the worm screw (11) and with the inner wall (18) of the bearing (14) that faces said end (16). The invention can be used for reconstruction of a missing or deficient osseous segment by means of osteogenic distraction.Linvention concerne un distracteur mandibulaire intraoral sur mesure, du type comportant deux moyens dancrage (1, 2) fixés dans le corps mandibulaire en des points dancrage fixes, situés de part et dautre du cal osseux. Un tel distracteur est caractérisé en ce quil comprend : a) un rail cylindrique fileté (6) reliant les deux moyens d ancrage (1, 2), b) un chariot mobile (10) guidé à coulissement sur le rail (6) et fixé sur le segment osseux à distracter, ledit chariot mobile étant équipé dune vis sans fin (11) dont le filetage est complémentaire de celui du rail et coopère avec ce dernier, c) un axe (12) solidaire de la vis sans fin (11) et commandant la rotation de celle-ci, ledit axe, parallèle au rail (6), étant supporté par deux paliers (13, 14) agencés sur le chariot mobile (10), de part et dautre de la
