Radiographic and Histological Assessment of GBR Using DBB Compared to Spontaneous Bone Regeneration of Maxillary Defects , Resulted from Enucleation of Intra-bony Cystic Lesions

‐ Two groups of patients with maxillary cystic lesions indicated for enucleation. Onewill be subjected to guided bone regeneration while the other will be subjected tospontaneous bone regeneration. ‐ General pre‐operative procedures: ‐ All patients will undergo appropriate preparation involving periodontal therapy , proper oral hygiene measures in addition to endodontic treatment for the non‐vital teeth related to the lesion.intraoperative procedure: (both groups) ‐ Scrubbing and draping of the patient will be carried out in a standard fashion usingbetadine surgical scrub. ‐ Local anesthesia will be administered (articaine hydrochloride 68 mg/1.7 ml +adrenaline 0.017 mg/1.7 ml injectable solution. ‐ Flap design: a sulcular incision will be done , extending two teeth beyond the areaof interest followed by two oblique incisions on either side of the flap. A fullthickness mucoperiosteal flap will be raised to expose the area occupied by thelesion. ‐ After flap reflection, the exposed bone related to the lesion will need to beremoved to provide adequate accessibility before enucleation of the lesion. ‐ The specimens will be fixed in 10% formalin for pathological examination.Intra‐operative procedures ‐ continued in Study Group (GBR group) The intra‐bony defectwill be filled with Deproteinized Bovine Bone. In Both groups: Titanium mesh will betailored with 3mm overlap at the edges to cover the bone window completely and fixed tothe bone using mono‐cortical titanium screws.This is followed by: ‐ proper decompression of soft tissue will be applied to achieve tension‐reducedsuture. ‐ Primary closure will be performed using 4‐0 vicryl sutures. ‐ Sutures will be removed one week postoperatively.Postoperative medications:For both groups, postoperative antibiotic course of amoxicillin+ clavulanic acid 1 g tab(Augmentin) will be prescribed for one week and isobutylphenylpropionic acid 600 mg tab(Brufen) twice daily for one week. One shot of dexamethasone 8 mg vial will beadministered intramuscularly immediately after the surgery together with ketorolactromethamine 30 mg .Postoperative care and instructions: ‐ Cold compresses will be applied for 10 minutes every 30 minutes for the first 24hours postoperatively replaced by warm fomentation with the same rate for the nexttwo days. ‐ Patients will be advised to maintain good oral hygiene and oral hygiene rinses using2% chlorohexidine gluconate mouth rinse for a week starting from the secondpostoperative day (three times daily) ‐ Soft diet is recommended for the first 48 hours. ‐ The patients will be recalled after two days, after one week, at the end of thefirst month and then at three and six months to monitor the soft tissue healingwhere the sutures were removed after one week, then at the sixth months to evaluatethe bony healing.Radiographic assessment will be achieved by CBCT scan immediately postoperative todetermine the baseline bone density and 6 months postoperatively to evaluate the changein the bone density . A total of three scans will be taken for each patient.6 months after the surgery ,titanium mesh and the screws will be removed , core biopsywill be taken for histological assessment and implant/s will be placed.