Digital Intraoral Scanning With and Without Prefabricated Landmarks Versus Conventional Impression Technique

Inclusion Criteria: * patients with completely edentulous mandible, non-smokers, 50-70 years in age, have Good oral hygiene and motivation. Exclusion Criteria: * patients with major systemic diseases that may affect osseointegration as uncontrolled diabetes mellitus, the need for extensive bone grafting in planned implant site, pregnancy, patients under bisphosphonate treatment, and limited mouth-opening for executing the guided implant surgery.