Accuracy of Conventional and Digital Methods of Obtaining Full-Arch Dental Impression (In Vitro Study)

IntroductionThe current gold standard is a conventional impression made with various impression materials and trays and results in a gypsum cast. With the development of milling and printing materials in dentistry, especially zirconia, a digital model has become increasingly important.ObjectivesTo compare the accuracy of the conventional impression scan (CIS), gypsum cast scan (GCS), and digital impression scan (DIS) to obtain a full-arch digital model.Materials and methodsA resin reference cast was fabricated. It was scanned by an extra-oral scanner to measure its accuracy as a reference scanner. Eight conventional impressions of the reference cast were taken by polyvinyl siloxane and scanned. After that, they were poured with type IV dental stones and scanned too. The reference cast was scanned by an intraoral scanner eight separate times. Digital models within each group were superimposed individually to measure precision. In addition, each model from each group was superimposed on one model from the reference scanner precision group to measure trueness.ResultsThe reference scanner showed the highest accuracy among groups with a precision of 1.5±0.8 µm and a trueness of 5.5±1.9 µm (P