Though first used in some capacity as far back as the 1980s, it has only been in the last decade or so that its use has become commonplace thanks to major advances in the associated technology. Despite its potential to improve the design and creation of dental restorations, many dentists remain hesitant to adopt it. This guide aims to provide an overview of CAD/CAM, how it works, its core uses, advantages and disadvantages.
A simple definition of CAD/CAM dentistry is the use of digital software to design and manufacture dental restorations and prostheses. CAD stands for computer-aided design and CAM stands for computer-aided manufacturing.
The technology can be used to create crowns, dentures, inlays, onlays, bridges and veneers among other things. The speed of the CAD/CAM process allows for dental prosthetics to be designed, manufactured and delivered to the patient in quick time, sometimes the same day. The wider system of using computer assisted technologies to produce restorations is known as CEREC (Chairside Economical Restoration of Aesthetic Ceramics).
Once any necessary prep has been completed, an intraoral scanner is used to scan the necessary teeth and oral regions. The captured images are then imported onto a computer ready for the prosthetic to be designed. Designing can be done either chairside by the dentist or in a lab. Once designed, the digital impression is then transferred across to a milling machine which mills the final product out of a CAD/CAM block. The milled prosthetic is then stained and glazed to improve its appearance. Prior to this it may also need firing in a ceramic furnace for crystallisation and sintering, although some blocks such as GC LiSi Initial Blocks are fully crystallised to remove this step. Once inside the patient’s mouth, the prosthetic can be cemented or bonded into place, then adjusted as required.
A CAD/CAM block is a solid block that is milled to produce a final or temporary restoration/prosthetic. CAD/CAM discs are also available in a circular shape.
The block is placed into a milling machine and cut to shape to match the imported digital design. This process can take anywhere between 10 and 25 minutes depending on the size of the design and speed of the milling machine.
CAD/CAM blocks come in various materials. These include zirconia, lithium silicate, ceramic and resin. Lithium silicate and zirconium ceramic blocks are the two most widely used materials.
Both lithium silicate and zirconia CAD/CAM blocks are considered full-coverage blocks, meaning they are suitable for both anterior and posterior high-strength restorations.