Three-Dimensional Bone Augmentation of Severely Atrophied Posterior Mandibular Alveolar Ridges Using Customized-3D Zirconia Barriers Versus Pre-bent Titanium Mesh

Inclusion Criteria: * Patients are systemically medically free according to the American Society of Anesthesiologists (ASA) considered as ASA I. * Ability to maintain good oral hygiene as evidenced in recall visits. * patients who had a partial or completely edentulous alveolar ridge with apparent 3D defect following teeth loss. * All patients were free from any local or general disease that may interfere with bone healing and had no history of previous grafting procedure at the designated edentulous ridge. * The ridge had to exhibit severe vertical and horizontal (3D) alveolar ridge deficiency with alveolar ridge height less than 7 mm from the alveolar crest to the inferior alveolar canal and width less than 5 mm which was firstly measured by CBCT, or a clinically apparent increase in inter-arch space relative to the adjacent natural teeth. * Pre-operative clinical assessment of soft tissue coverage was done to cover the graft and its membrane, in addition to assessment of occlusion and inter-arch distance should allow for the graft, membrane, implan and the future prosthesis. Exclusion Criteria: * Smoker (\> 25 cigarettes/ day). * Patients undergoing radiotherapy or chemotherapy * Patients having infection or local lesions in the area of surgery. * Patients with diabetes mellitus or bone diseases which may compromise the results. * Patient with poor oral hygiene or active periodontal disease. * Patient with limited mouth opening. * Participation in other clinical trials