Pycnodysostosis is a rare osteopetrotic disorder. This report describes a case of a 3(1/2)-year-old boy with pycnodysostosis who presented with severe snoring. The snoring was the result of a pharyngeal narrowing due to a hypoplastic mandible. Surgery consisted of a bilateral rib graft, which allowed an enlargement of the pharynx by acting both on an anterior projection of the chin and a decrease of the glossoptosis. A significant reduction of the snoring and an excellent mouth aperture were obtained. This technique is ideal for such patients presenting a high risk of infection, nonunion, and secondary fracture.