The purpose was to evaluate the accuracy of traditional and digital implant level impression procedures by using three-dimensional superimposition analysis , and evaluate the passive fit of screw- retained implant supported restorations fabricated using conventional and digital impression techniques in bilateral distal extension cases (class I kennedy classification)

Eight patients who had missing all mandibular posterior teeth except first premolars were included in this study. In each patient, 4 implants were placed, 2 in each side to support 3 units screw retained zirconia restorations. Three months after implant placement, each patient underwent two implant level impression techniques (n=8) for each technique: Conventional implant impressions CII (pick-up, splinted transfers), and digital implant impressions DII were captured with TRIOS 3 Shape intraoral optical scanner. In this study, digital impression was considered as a reference data.

Inclusion Criteria:

• All participants have sufficient bone length and width for implant insertion.
• General health of the patients was evaluated by taking a full medical history to ensure that these patients were free from any systemic conditions that would have impaired implant osseointegration
• Good oral hygiene
• Sufficient inter-arch spaces
• The opposing arch was almost dentulous, and any missing teeth were restored using a fixed partial denture.

Exclusion Criteria:

• parafunctional habits
• Heavy smoking
• Those patients with systemic diseases that may influence soft or hard tissue healing.
• Patients with a history of radiation therapy in the head and neck region.
• Patients with a history of radiation therapy in the head and neck region.