The advantage of the CAM CAD

CAD/CAM dentistry is quickly digitizing a process long known for being time-consuming and nearly entirely manual. Using the latest design and manufacturing techniques, CAD/CAM has started a new era in dentistry characterized by faster procedures, more efficient workflow and a better overall patient experience. In this blog, we’ll take a deep dive into CAD/CAM dentistry, including how it works, what it involves, its pros and cons, and the technologies involved.

First, let’s define some terms.

Computer-aided design (CAD) refers to the practice of creating a digital 3D model of a dental product with software, as opposed to a traditional wax-up.

Computer-aided manufacturing (CAM) refers to techniques like CNC milling and 3D printing that are done by machines and controlled by software, as opposed to traditional processes like casting or ceramic layering, which are entirely manual.

CAD/CAM dentistry describes the use of CAD tools and CAM methods to produce crowns, dentures, inlays, onlays, bridges, veneers, implants, and abutment restorations or prostheses.

In the simplest terms, a dentist or technician would use CAD software to create the virtual crown, for example, which would be manufactured with a CAM process. As you can imagine, CAD/CAM dentistry is more replicable and scalable than conventional methods.

The evolution of CAD/CAM dentistry

The introduction of CAD/CAM dentistry has changed how dental practices and dental labs handle impressions, design, and manufacturing.  

Prior to CAD/CAM technology, dentists would take an impression of the patient’s teeth using alginate or silicone. This impression would be used to make a model out of plaster, either by the dentist or a technician in a dental lab. The plaster model would then be used to manufacture the personalized prosthetics. From end to end, this process required the patient to schedule two or three appointments, depending on how accurate the end product was.

CAD/CAM dentistry and its associated technologies have made a formerly manual process more digital.  

The first step in the process can be done directly from the dentist’s office when the dentist records a digital impression of the patient’s teeth with an intraoral 3D scanner. The resulting 3D scan can be sent to a dental lab, where technicians open it in CAD software and use it to design a 3D model of the dental part that will be printed or milled.

Even if a dentist uses physical impressions, dental labs can take advantage of CAD technology by digitizing the physical impression with a desktop scanner, making it available within CAD software.  

Advantages of CAD/CAM dentistry

The biggest advantage of CAD/CAM dentistry is speed. These techniques can deliver a dental product in as little as one day — and sometimes the same day if the dentist designs and manufactures in house. Dentists can also take more digital impressions per day than physical impressions. CAD/CAM also allows dental labs to finish far more products per day with less effort and fewer manual steps.

Because CAD/CAM dentistry is faster and has a simpler workflow, it is also more cost-effective for dental practices and labs. For example, there is no need to buy or ship materials for impressions or casts. In addition, dental labs can manufacture more prosthetics per day and per technician with these technologies, which can help labs deal with the shortage of available technicians.

CAD/CAM dentistry typically requires fewer patient visits, too — one for the intra-oral scan and one for placement — which is much more convenient. It is also more comfortable for patients because they can be scanned digitally and avoid the unpleasant process of holding a viscous wad of alginate in their mouth for up to five minutes while it sets.

Product quality is also higher with CAD/CAM dentistry. The digital accuracy of intraoral scanners, 3D design software, milling machines and 3D printers often produces more predictable results that fit patients more accurately. CAD/CAM dentistry has also made it possible for practices to handle complex restorations more easily.

dental milling machines

Applications of CAD/CAM dentistry

The applications of CAD/CAM dentistry are primarily in restorative work, or the repair and replacement of teeth that have decay, damage, or are missing. CAD/CAM technology can be used to create a wide range of dental products, including:

Crowns

Inlays

 Onlays

Veneers

Bridges

Full and partial dentures

Implant restorations

Overall, CAD/CAM dentistry is appealing because it is faster and easier while frequently delivering better results.

How does CAD/CAM dentistry work?

CAD/CAM dentistry follows a straightforward process, and in cases where all processes are done in-house, can be completed in as little as 45 minutes. The steps typically include:

Preparation: The dentist removes any decay to ensure the patient’s teeth are ready for scanning and restoration.

Scanning: Using a handheld intraoral scanner, the dentist captures 3D images of the patient’s teeth and mouth.

Design: The dentist (or another member of the practice) imports the 3D scans into the CAD software and creates a 3D model of the restoration product.

Production: The custom restoration (crown, veneer, denture, etc.) is either 3D printed or milled.

Finishing: This step depends on the type of product and material, but may include sintering, staining, glazing, polishing and firing (for ceramic) to ensure accurate fit and appearance.

Placement: The dentist installs the restorative prosthetics in the patient’s mouth.

Digital impressions and scanning

One of the biggest advantages of CAD/CAM dentistry is that it uses digital impressions, which are more comfortable for patients and help dentists get a 360-degree view of the impression. In this way, digital impressions make it easier for dentists to ensure the preparation is well done so the lab can make the best possible restoration without the need for another patient appointment to make further adjustments.

Digital impressions are made with intraoral 3D scanners, which are slim handheld devices that are placed directly in the patient’s mouth to scan the teeth in seconds. Some of these wand-like devices even feature thinner tips to accommodate patients who can’t open their mouths very wide.

These scanners may use video or LED light to quickly capture high-resolution, full-color images of the patient’s teeth and mouth. Scanned images can be exported directly into CAD software for design with no intermediate steps. The digital images are more accurate, more detailed, and less prone to error than conventional analog (physical) impressions.

Another important benefit of this approach is that the dentist can ensure there is enough space for the antagonist and check the quality of occlusion. In addition, the dental lab can receive the digital impression a few minutes after it is prepared and reviewed by the dentist without the time or cost typically associated with shipping a physical impression. 


CAD workflow for dentistry

After the 3D scan is brought into the CAD software application, the dentist or a design specialist can use the software to create the crown, veneer, denture, or implant.

These software applications often guide the user through the process of creating a product that matches the shape, size, contour and color of the patient’s tooth. The software may allow the user to adjust thickness, angle, cement space and other variables to ensure the proper fit and occlusion.

CAD software may also include specialized tools, such as a contact analyzer, occlusion checker, virtual articulator, or anatomy library, all of which help enhance the design. The path of insertion axis may also be determined. Many CAD applications also use artificial intelligence (AI) to simplify, streamline and automate many of these steps or provide suggestions for the user to follow.

CAD software can also assist with material selection because each material offers a different combination of flexural strength, mechanical strength and translucency.