ACCURACY OF DIGITAL VS CONVENTIONAL IMPRESSION TECHNIQUES: A NARRATIVE REVIEW

Abstract

Computer-aided design and manufacturing (CAD/CAM) techniques are increasingly used in dental restorations, yet many approaches start with traditional gypsum casts based on conventional impression techniques. Despite advancements in impression techniques and materials, results in clinical practice often remain unsatisfactory. Digital impressioning procedures offer promise in improving restoration accuracy by eliminating error-prone conventional methods and ensuring high standardization. This review aims to compare the accuracy of digital versus conventional impression techniques in dentistry. A comprehensive search of electronic databases from 1987 to 2023 was conducted, focusing on English-language articles in peer-reviewed dental journals. Inclusion criteria required studies comparing both digital and conventional techniques. Results from PubMed, Cochrane Central Register of Controlled Trials, and Web of Science yielded 19 articles meeting selection criteria. While systems like CEREC have been commercially available for over 25 years, newer digital impressioning devices like Lava C.O.S., iTero, and TRIOS are gaining prominence. The marginal accuracy of restorations is crucial for periodontal health, with internal fit important for restoration longevity. Studies comparing digital and conventional impressions show comparable accuracy, meeting information transfer requirements from patient to laboratory. Digital impressions offer advantages in reducing chair time and patient discomfort, leading to improved treatment effectiveness. However, challenges remain in establishing protocols for evaluating intraoral impression accuracy and ensuring precision. Overall, digital impression systems demonstrate comparable accuracy to conventional techniques, with added benefits in efficiency and operator ease, though challenges with distal targets persist.