Metformin and Alveolar Cleft

* Completed medical history will take for all patients. All patients' guardians were informed about the procedure, the possible postoperative complications, and requested to sign an informed consent that was translated into Arabic language. * Patients were randomly divided into two equal groups by means of sealed envelopes: * Group A ( study group) 18 patients who received a combination of illiac cancellous bone graft and 2ml of 1% metformin gel (20mg of metformin with 2% hydroxymethyl cellulose) * Group B (control group): 18 patients who received illiac cancellous bone graft and 2 ml placebo gel (2% hydroxymethyl cellulose) Preparation of the Donor Site (Anterior Iliac Crest) and Harvesting of the Bone Graft * A standard incision will be done to expose the anterior iliac crest. The cancellous bone graft will be harvested using 8 mm diameter trephine bur (KLS Martin, city, Germany). The graft will be harvested by molt and surgical curettes. The wound was then closed in the usual manner. * For group A, the patients will receive iliac bone graft mixed with metformin gel and packed into the defect While in group B, the iliac bone graft will be mixed with placebo gel and packed into the defect. * The labial flap was then approximated to the palatal one and sutured over the cleft area beginning with a horizontal mattress suture followed by multiple interrupted sutures to completely cover the grafted area