Transfer Accuracy of Closed-Tray Implant Impressions: An In Vitro Comparison Across Five Implant Systems

This in vitro study aimed to evaluate and compare the transfer accuracy of implant impression systems utilizing transfer caps for the closed-tray technique across five different implant systems, with the open-tray (pick-up) technique serving as a reference.

Six bone-level implants from different manufacturers (SIC Invent, BEGO, Bredent, Camlog, and Straumann) were placed in a 3D-printed custom-designed master model. The master model with the inserted implants and the attached scan bodies served as the reference model. The implant master model was duplicated 10 times by means of conventional impressions. Based on these impressions, the master models were fabricated. Finally, closed-tray impressions using transfer caps were taken ten times for each system, and one system (SIC Invent) was also tested using the open-tray technique. Polyether impression material and standardized laboratory protocols were used throughout. The accuracy of the impressions was evaluated through 3D superimposition using Final Surface software, comparing master models to a reference model. Deviation measurements were statistically analyzed using rank-based ANOVA.

No statistically significant differences were found in the transfer accuracy among the five closed-tray systems. Similarly, the closed-tray technique showed comparable precision to the open-tray technique.

Closed-tray implant impressions using transfer caps can achieve transfer accuracy on par with the open-tray technique. These findings support the potential clinical reliability and reproducibility of closed-tray systems across multiple implant manufacturers.