Comparison of functional and esthetic outcomes in digital versus analog rehabilitation of one-piece screw-retained implant crowns placed at second stage surgery

PURPOSE: Analog and digital impressions are established procedures for restoration of single-tooth implants. In this study, single-tooth implants were restored with definitive restorations during second-stage surgery. Analog and digital workflows were compared.

MATERIAL AND METHODS: Eighty single-tooth implants were examined in total. In 40 implants, an index was taken immediately after implant placement using composite resin to fabricate the final crowns (analog workflow). For the other 40 single-tooth implants, intraoral intraoperative scans were performed (digital workflow) during primary surgery. The custom-fabricated screw-retained crowns were placed during second-stage surgery. Photographs and examinations for the scores were taken at the time of the follow-up visit, 1-4 years after placement of the crowns. The number of treatment appointments required was recorded and the modified pink esthetic score (PES) was determined. Additionally, the functional implant prosthetic score (FIPS) was measured.

RESULTS: The mean PES was 12.15/14 for the digital workflow and 11.95/14 for the analog workflow. The most common deficit was incomplete papillae for both workflows. Three treatment appointments were required for both workflows: (1) Scan and/or impressions making and patient consent, (2) implant placement, and (3) second-stage surgery with crown insertion. The FIPS was 9.1/10 for the digital workflow group and 9.2/10 for the analog workflow group. Common deficits presented as missing papillae as well as open approximal contacts. The FIPS was not significantly different between workflows (p = 0.679). The PES also did not show a statistically significant difference for both workflows (p = 0.654), however, the analog workflow showed better values for the papillae (p < 0.05). A significant difference was also found in the other PES values, with the digital workflow showing better results here (p < 0.05). A chronological analysis of the results of the digital technique showed that the cases treated last had significantly better values than the cases treated first.

CONCLUSIONS: According to the results of this study, both workflows allowed placement of the definitive crowns on single-tooth implants during second-stage surgery. Both workflows were found to be equivalent in terms of esthetic results in this study, although the digital workflow demonstrated a learning curve.