Device for activating mandibular growth, maxillary growth and mandibular advancement, the device having a first rod with a front end and a rear end; a second rod with a front end and a rear end; the first and second rods having mutually different lengths; a first pivoting articulation for connecting the front end of the first rod to a first dental arch of a person; a second pivoting articulation for connecting the front end of the second rod to the second dental arch of the person; a third pivoting articulation interconnecting the rear ends of the rods, the third pivoting articulation being connected to the dental arch carrying the shortest rod with the aid of elastic means returning the device to the closed position.