The next generation of intraoral scanning

Sirona Dental Systems has launched a second acquisition camera unit for its CEREC AC chairside CAD/CAM system at the "CEREC 27 and a Half" anniversary event staged recently in Las Vegas. More than 4,000 dental professionals who attended the event at the Venetian Resort Hotel Casino gained first look at the new CEREC Omnicam that promises powder-free image acquisition and unique full colour live streaming image capture whilst maintaining detail and precision.

CEREC is now used in more than 36,000 dental practices worldwide and one of the foundations of the system has always been the ease of imaging with all generations of cameras. Despite the fact that the system required an opaque powder to be applied to the teeth, the intraoral scanning with the previous generation of camera, the Bluecam, was quite easy and set the standard for all other systems (Figure 1). In a matter of seconds, users could spray a thin coat of powder on the teeth and use the Bluecam to capture individual images. Those images would then be processed by the software to create a virtual model on which the restoration could be designed allowing the clinician full control over the contacts, contours and occlusion (Figure 2).

The Omnicam differs in three main ways from the Bluecam which, up to this point, was considered the gold standard in intraoral imaging in dentistry:

1. Omnicam is completely powder-less. Simply take the camera and use it in a similar motion to an intraoral camera to capture images in the mouth. The camera captures in vivid detail the hard and soft tissues and allows the user to differentiate dentin from enamel from soft tissue. Figure 3 shows the actual scan of a prepared tooth as it's being imaged with the Omnicam. There is no powder required on the teeth prior to imaging.

2. The Omnicam images in full colour. Virtually every other intraoral imaging system takes its images in black-and-white and renders the virtual model in a graphical representation of the teeth. The Omnicam, on the other hand, not only allows the user to visualize the teeth in full colour, it also renders the models in true photorealistic imaging. The models are not a graphical representation of the acquired information, but are in fact of the quality of a high-resolution photo. This allows the user to design the restorations on a true representation of the model. The colour capabilities were already shown in Figure 3 and the virtual model that is created by the colour capture is visualized in Figure 4.

3. The images that are captured by the Omnicam are in live streaming of data format, not as individual images. The advantage of this is that the user simply waves the camera over the area they want to capture - without any powder - and the live streaming of data feed fills in all the missing data to create a virtual model. No longer is the user dependent on individual images to fill in the missing data. The clinician can simply scan the desired arch without having to worry about any images "stitching". Figure 5 shows the Omnicam capturing the buccal bite utilizing a live stream in colour.

While other imaging systems have had one or two of these features, until the Omnicam, no other system has been able to combine all three features in a single system. Video capture has been done previously, but never with the ease of the Omnicam and with the absence of powder. Colour has been present on other systems, but the systems that used colour had a camera that was slow and clunky to use and captured individual images, which require a long time to stitch together to form a virtual model. Some systems have had powder-free capabilities, but the imaging was archaic and the data captured rendered virtually useless models. Not until the Omnicam has there been a system that is powder-free, captures live streaming of data and is in colour. The result is a system that is easy to use by clinicians and renders accurate and precise models quickly and efficiently. Having used the Omnicam for several months now, the authors feel that it is a major step forward in the world of CAD/CAM dentistry.

For existing CEREC owners, it's important to understand that once the image is acquired with the Omnicam, the data is processed by the same 4.0 software that was released by Sirona in 2011 and used by Bluecam users. This ensures that the learning curve is minimal. The software is obviously modified to work with the Omnicam, but in all other aspects has the same tools and features as the regular 4.0 software that is currently available with the Bluecam - allowing users to easily and rapidly integrate it into their practices.

Case study

A patient presented to the office with decay of the pre-molars. The teeth were prepped and captured with Omnicam. Figure 6 shows the prepared premolar teeth captured with Omnicam. After administering anaesthesia, the teeth were prepared for full coverage crowns and imaged with the Omnicam. The preps, buccal bite and opposing teeth were captured using intraoral scanning and the models were digitally articulated in the software (Figure 7).

After articulating the models, the margins were drawn on the virtual models that were created with the intraoral scanning. The photorealistic models were a true representation of the preparations, where not only the preps were captured but also the surrounding tooth structure with their appropriate restorations such as amalgams (Figure 8).

Once the margins were drawn, the software rendered the proposals (Figure 9). The proposals were based on the same Biogeneric principles that have been used in previous CEREC software versions. All of the familiar tools and menu items that are present in the Bluecam are available in the Omnicam software. The opposing arch was turned on to accurately modify the proposals as well as the occlusion (Figure 11).

After completion of the design, the restorations were milled with lithium disilicate e.max blocks.

Another advantage of the Omnicam is that it can be used to verify intraoral fit of the milled restorations. Due to the high resolution of the camera, the visual verification of the fit of the restorations can be performed with ease. Figure 11 shows how the marginal fit of the restorations is verified visually using the Omnicam. The milled restorations were crystallized using the Ivoclar Fast Fire cycle and bonded in place using Multilink adhesive cement.

The Omnicam represents a major leap forward in CAD/CAM imaging. Its ease-of-use and clinical accuracy sets the bar for all other systems going forward. It is the authors' opinion that all current and future CEREC clinicians will benefit significantly from utilizing this technology in their practices.

About the authors

Dr Sameer Puri is the Director of CAD/CAM at the Scottsdale Center for Dentistry. He is the co-founder of www.cerecdoctors.com and has been a CEREC beta tester since 2005.

Dr Armen Mirzayan is co-director of CAD/CAM at the Scottsdale Center for Dentistry and a former clinical assistant professor at the University of Southern California Dental School. He has been a CEREC user since 2000, a chief beta tester for Sirona for the past 8 years and is co-founder of www.cerecdoctors.com.

This article was originally published on www.cerecdoctors.com, a website dedicated to CEREC online education where clinicians can learn the ins and outs of CEREC dentistry from basic training to more advanced techniques such as anterior aesthetics.

NB: Dentists purchasing a CEREC AC can opt for either the Omnicam or Bluecam. Omnicam cannot be retrofitted to existing CEREC AC units with Bluecam.