Effect of Open Tray Versus Digital Impressions on the Passivity and Prosthetic Complications of Full Arch Screw-retained Prosthesis

Inclusion Criteria: * Completely edentulous patients with sufficient inter-arch space to receive fixed prosthesis (Crown height space 9-15 mm per arch) * Completely edentulous patients with 4 implants in mandible and/ or 6 implants in maxilla * sufficient bone volume for implant placement without graft a confirmed by CBCT * adequate zone of keratinized mucosa ( \> 2mm width) * All genders * Acceptable oral hygiene * Cooperative patients * Controlled systemic diseases ( Diabetes, hypertension) Exclusion Criteria: * Completely edentulous patients with sufficient inter-arch space to receive fixed prosthesis (Crown height space 9-15 mm per arch) * Completely edentulous patients with 4 implants in mandible and/ or 6 implants in maxilla * sufficient bone volume for implant placement without graft a confirmed by CBCT * adequate zone of keratinized mucosa ( \> 2mm width) * All genders * Acceptable oral hygiene * Cooperative patients * Controlled systemic diseases ( Diabetes, hypertension)