By Danny Chan
If anyone understands the uniqueness of teeth, it is the dentist. That being the case, it shouldn’t be hard for a dentist to appreciate the high level of customization that 3D printing, with its additive mode of manufacturing, brings to the construction of prosthetic teeth and oral appliances. 3D printing has, for sound reasons, been widely tipped the next big technology to watch for in the dental space – and dentists have been paying close attention.
Those of you who have been scouting for next-generation dental applications would probably have heard of 3DRPD. As one of the world’s leading 3D printing dental solution providers, the tech firm specialises in 3D printing of Removable Partial Dentures (in cobalt chrome). With more than 50,000 restorations in the mouth, theirs is a proven solution that uses laser-sintering technology to manufacture digitally-modelled denture designs directly in 3D printers. This hassle-free process does away with casting and plastic patterns while allowing cost-efficient and speedy results.
Australian dentists who can’t wait to reap the rewards of 3D printing can google up Intelligent Dental Solutions (iDS), the exclusive partner for 3DRPD in Australasia.
Intelligent Dental Solutions is a forward-thinking dental laboratory headed by Joe Nguyen and Fred Carlstrom. Founded by Joe in 2001 as a full-service lab, the company officially entered the CAD/CAM arena when Fred joined two years later. 3DRPD is the latest hi-tech venture for the enterprising duo – whose unconventional slate includes an open-source cloud system that connects lab owners and dentists. True to the partners’ pedigree, Intelligent Dental Solutions is the only lab in Australia that provides full service 3D printing of RPDs direct to metal. In addition, they also 3D-print dental models, splints and copings.
The 3DRPD distributorship was forged during the last IDS exhibition in Cologne, Germany. The partners were “immediately impressed” by the technology and products on display – which Fred believes, reinforces 3DRPD’s position as a committed technological supplier:
“It is not as simple as it may sound. It took 3DRPD best part of two years to develop their own patented powder material and perfect the manufacturing process. Each metal printer represents a large investment at around $700K and 3DRPD has got 15 of them – it’s not for the small investor.”
Dental 3D-printing technology and workflow
In regards to the 3DRPD workflow, Fred says the all-digital process is “less labour intensive and far cleaner”. Compared with the traditional casting process, it doesn’t have as many health and environmental issues.
To manufacture the partial chrome, what the prosthetist needs is a dental model with a prescription on what is required. The dental model can be produced using an Intra-Oral 3D scanner or a 3D scan of an impression/model obtained by a desktop dental scanner. The model scan is transferred to a partial design software, inside which the chrome geometry is built. All undercuts are removed and the partial geometry is constructed in full 3D. Once finished, the chrome part is exported to the 3D printer as a STL file
The “build file” of the 3D CAD model is sliced into layers by the machine software, which then creates a path for the focussed laser beam to melt and sinter fine metal powder to the perimieter of the part. The part is constructed additively layer by layer until the build is complete. Once finished, the partial chrome is polished, fitted to the model and ready for fitting the teeth.
Stronger and faster – with superior patient benefits
Fred explains that the laser sintering process results in 3D-printed RPDs’ structural integrity being superior to conventional cast chromes. “The powder material is manufactured under strictest quality control resulting in a very homogenous material with no porosity. The powder material is far more consistent in its composition than materials used for conventional casting.”
“The 3D-printed frames are much stronger and retain their shape much longer. Fatigue resistance tests of clasps over 6000 cycles has shown that 91% of 3DRPD clasps return to their original shape where only 25% of traditional cast clasps retain their memory on a distance of 0.2mm.”
Price-wise, he reckons the cost of frames produced by 3DRPD – made with FDA-compliant materials – is comparable to quality cast frames despite having many advantages over them. While periodic adjustments of 3DRPD frames by a dentist will still be required, they can often last for 6 months without adjustment. As for turnaround speeds, it takes 1-5 hours for a resin build, and 8-10 hours for its metal counterpart.
“Most 3D printers can build a whole platform full of parts as quickly as a single part. If you fill up the platform, the time for each part will be greatly reduced.”
Apart from partial frames 3DRPD can also 3D print other restorative parts like dental bars and metal copings. Dental bars have become very popular due to price and functionality. A major feature with 3D printed dental bars is that they can have complex features and undercuts without adding extra cost.
Fred says 3DRPD users gave high marks on their experience with the 3D-printed frame. Quoting survey results, he says that 3DRPD fared better than cast chromes when it came to patient benefits – ranging from comfort and aesthetics to retention and stability to restoring speaking and chewing functions. It is also a healthier subsitute, Fred explains:
“There is no Nickel (Ni), Chromium (Cr) or contamination in the 3DRPD frames. There are no allergy issues for patients sensitive to contaminations.”
A former Mechanical Engineer with over 30 years’ experience implementing CAD/CAM in a wide variety of industries, Fred sees a dentally-paved future for 3D printing:
“The price for smaller printers is coming down and will make 3D printing available to many smaller labs. Many new materials will be available in the future in particular bio-compatible materials that can be 3D printed and used in the mouth for long periods of time.
Although the technology has yet to be fully exploited, Fred believes it has already reached a point of maturity and that it is as good a time as any to jump on the bandwagon.
For more information contact Intelligent Dental Solutions
Phone: 1300 445 115 firstname.lastname@example.org www.ids-dental.com.au