Guided Biaxial Alveolar Distraction Device in Posterior Atrophic Mandible

Inclusion Criteria: * Patients with the posterior atrophic mandible. * The distance from the alveolar crest to the upper border of the canal is not less than 5 mm. * Adult patients from 30-60 years old with no gender predilection who agreed to present for follow-up visits for a minimum postoperative period of 4 months. * Patientswithanadequateoralhygiene. * The patient should be psychologically accepting of the involved procedures. Exclusion Criteria: * Medically compromised patients contradicting operation (ASA III, IV \& V). * Patients receiving radiotherapy or chemotherapy or bisphosphonate. * Bonediseases(Osteoporosis,Osteopetrosis,Osteomalacia...etc.) * Any habits that might retard healing such as heavy smoking and alcoholism. * A history of any grafting procedure at the designated area.