Inclusion Criteria:  The presence of horizontal and vertical alveolar defects in both jaws, inadequate for the placement of at least two fixtures, even ≤6 mm long ones; ≥ 18 years; informed consent signed.  Exclusion Criteria:  acute or chronic infections in the head and neck; smoking >10 cigarettes per day; uncontrolled diabetes (glycated hemoglobin level > 7 mg/dL); a history of radiation therapy in the head or neck region; current antitumor chemotherapy; liver, blood, or kidney disease; immunosuppression; everyday corticosteroid use; pregnancy; inflammatory and autoimmune disease of the oral cavity; poor oral hygiene and motivation