COMPARISON OF THE ACCURACY BETWEEN DIGITAL AND TRADITIONAL IMPRESSIONS FOR FABRICATION OF IMPLANT-SUPPORTED CROWN

Subject. Currently, in prosthetic dentistry, significant attention is being paid to digital protocols. The conventional method of fabricating dental prostheses involves using silicone impression materials to obtain a working cast – a replica that closely mimics the spatial position of implants within the jawbone. The accuracy of this cast is a critical factor influencing the outcomes of prosthetic treatment. When performing implant-supported prosthetics, clinicians employ well-documented protocols using either open-tray or closed-tray impression techniques. Numerous scientific studies have compared the accuracy of conventional impressions to that of digital impressions. However, a comparative analysis of conventional impressions made with open-tray, closed-tray techniques and digital impressions has not been found in the literature. Therefore, conducting this comparative study represents a relevant and timely research objective. Objectives. A comparative analysis of implant-level impression techniques for single implant-supported crowns with the aim of minimizing prosthetic misfit and providing clinical recommendations. Materials and methods. A reference model fabricated via additive manufacturing from an STL file acquired through an intraoral scan of the patient served as the control. Conventional impressions were made using a polyvinyl siloxane material, while digital impressions were acquired with a 3Shape TRIOS intraoral scanner. Results. The smallest deviation from the reference model in the centro-occlusal (CO) and axio-occlusal (AO) zones was observed for the digital impression technique (17.5 ± 0.7 µm and 50.8 ± 2.4 µm, respectively), followed by the open-tray technique (28.5 ± 1.9 µm and 58.0 ± 1.3 µm, respectively). The closed-tray technique demonstrated the lowest accuracy (101.8 ± 6.3 µm and 99.0 ± 1.7 µm, respectively). Regarding the medio-axial (MA) zone, the most accurate results were obtained with the closed-tray and open-tray techniques (8.5 ± 0.7 µm and 31.8 ± 0.9 µm, respectively), while the digital impression method yielded the least accurate result (63.3 ± 3.0 µm). Conclusions. In conclusion, we would like to say that for taking precise impression from a single implant, it’s recommended to use a digital protocol and digital impression. For taking a conventional silicon impression, the open-tray technique showed the best results, being more accurate in compare the closed-tray technique.