Digital Options for Restoring Teeth

An intra-oral camera and a dental plaster model

There cannot be any doubt that the future of dentistry is digital. The first commercially available dental CAD/CAM system was produced by Siemens as long ago as 1985. It used optical scanning technology and a milling machine to make tooth coloured porcelain restorations.

In the intervening years optical scanning technology, digital manipulation software, computer hardware and dental porcelains have significantly improved. There are now a range of optical scanners available that provide an alternative to conventional impression taking. Manufacturers claim enhanced patient comfort, easier control of the gag reflex along with digital data that provides a permanent record without requiring physical storage space. (unlike conventional dental plaster models)

In order to adopt new technology we believe that it should be fundamentally faster, easier and most importantly, more precise than conventional alternatives. The question is always when to adopt new technology and we have never been early adopters. We prefer to adopt once the development process is well underway. While some of our patients may be happy to be part of an “experiment”, most prefer predictable outcomes.

We are currently considering our options for digital dentistry. In principle all systems begin with an intraoral scanner. The captured digital data can then be sent to a CAD/CAM system to make a restoration at the surgery. This has the advantage of the possibility to complete the restoration in a single visit.

The alternative is that the data can be sent by email to an appropriately equipped dental laboratory. There are then two options:

1. The restoration is designed on a computer and digitally manufactured.

2. A model is fabricated, possibly by 3D printing, and then a conventional restoration is made.

Ultimately the clinicians' choice will depend on their judgement of the suitability and long term clinical stability of the different materials available with each process. Early CAD/CAM systems failed to gain widespread use, not because they were expensive, but because the dental ceramics of that era were prone to mechanical failure, thus negating the value of the very clever technology.

The suitability of these systems for any given procedure depends on the degree of accuracy required. The current systems are excellent for case planning, planning and executing orthodontic tooth movement using “aligners” and for making single crowns. Studies have shown that they are not yet entirely predictable for big implant cases where conventional impressions produce more precise outcomes.

It should theoretically be possible to fuse the digital data from optical scanners and the data from Cone Beam Computer Tomography images to plan complex implant surgery cases. This data can be used to 3D print surgical guides which are intended to reduce the possibility of human error. This approach is not yet predictable enough to adopt routinely.

Digital dentistry is now a routine part of dental care and this will only ever increase.