With a digital impression system, the dentist or dental assistant captures an image of a tooth/teeth preparation. With some digital impression systems, once the area to be treated is anesthetized and free of saliva and blood, the teeth are lightly dusted with specially formulated titanium dioxide powder in order to scan both arches and the bite. Other systems (such as Cadent iTero and the impression technology that accompanies the E4D Dentist System for in-office CAD/CAM restorations) allow dentists to create a powder-free, three-dimensional image of the patient’s teeth.
The digital impression typically is captured using an intraoral wand that is inserted into the patient’s mouth and moved over the surface area of the tooth or teeth. Most digital impression systems use a chairside monitor to display the impression image as it is captured.
Additionally, most digital impression systems also rely on point-and-click capture, which requires the images to be pieced together to create the final digital impression. However, the Lava C.O.S system is the only one that uses three-dimensional real-time video capture to display live images on a touch-screen monitor. This live video capture creates the final digital impressions without the need to piece together data.
It takes approximately a minute and a half to capture a digital impression of prepared teeth. An impression of the teeth in the opposite arch takes just 45 seconds.
As the dentist reviews the electronic real-time image, he or she can enlarge and manipulate it for enhanced detail to ensure that any possible mistakes are identified and corrected onscreen before sending the digital impression electronically to the dental laboratory or in-office dental CAD/CAM system. The delivery workflow will vary depending on the digital impression system the dental practice works with. Current digital impression systems available for the dental office are digital impressions only or digital chairside CAD/CAM systems.
Digital impression systems — such as Cadent iTero, 3M ESPE Lava Chairside Oral Scanner (C.O.S.) and Sirona CEREC Connect — digitally record the tooth preparations and adjacent teeth in the arch or quadrant, as well as the opposing teeth and bite registration. The data is transmitted electronically to the dental laboratory for use in restoration fabrication.
Digital chairside systems — such as D4D Technologies E4D Dentist System and Cirona CEREC Acquisition Center (AC) — also record digital impressions, but the recorded data is used within the dental office to design, mill and deliver the final restoration in one appointment for same day dentistry.
The iTero and Lava Cos are the only digital system that can be used for all types of dental restorations, including bridges, crowns, inlays and onlays, and veneers. The other digital impression systems are designed for use with select types of ceramic and composite systems.