Effect of Metformin Gel on Guided Bone Regeneration Around Immediate Dental Implant at Posterior Maxillary Region

To evaluate, by standardized radiographic follow-up, whether locally delivered 1% metformin gel improves bone healing around immediately placed dental implants augmented with GBR.

Inclusion Criteria: * 1\. All patients were free from any systemic diseases according to criteria of Cornell Medical Index and its modification(184). 2\. Patent's age at least 18 years old. 3. Patients had remaining roots or badly decayed hopeless teeth indicated for extraction for immediate implant placement in the posterior maxilla region. 4\. Extraction socket has sufficient bone quality and quantity amenable for implant length that is not less than 10 mm and of suitable diameter. 5\. The implant recipient site should be free from any pathological conditions. 6. Patients with Good Oral Hygiene, and instructed for oral hygiene measures Exclusion Criteria: * Patients with bad oral hygiene. 2. Uncontrolled systemic diseases that complicate bone healing. 3. Presence of any pathology in the implant site. 4. Heavy smokers, alcohol or drug abuse patients. 5. Patients with para functional habits such as bruxism and clenching. 6. Conditions that might lead to alteration of bone region as osteoporosis or Paget's disease. 7\. Any medicines such as bisphosphonates or steroids that affect bone turn over. 8\. History of chemotherapy or radiotherapy.