A technique is described of true rebuilding of the mandibular crest using a combination of the visor-osteotomy (Härle, 1975) and a subperiosteal rib graft (Obwegeser, 1963 b). A preliminary report on 25 patients with a mean follow-up of 30 months leads to the following conclusions: the resorption in the anterior part ist 52% of the initial gain after 43 months. In the lateral regions 61% is lost. This compares favourably with other techniques. Impairment of sensibility, although usually acceptable, is the main drawback of the procedure.