Effect of Geometric Modifications of Implant Scan Bodies

Inclusion Criteria: * 1\. All selected patients will have four implants placed in the mandibular interforaminal region according to all -on -four concept. 2\. All selected patients have a healthy mucosa and with no clinical complications. 3\. All patients are cooperative and approve the proposed treatment protocol. Exclusion Criteria: * 1\. Patients who reject to participate in the study. 2. Patients who need implant placement as a result of previous implant failure.