Perfit Dental solutions – New Solutions to Old Problems
When it comes to new technologies, Denturists have largely been left on the outside looking in. While we’ve seen major advancements in crown and bridge (with systems like Cerec, which was globally released in 1986), 30 years later, digital technology has yet to make its way into main stream Denturism.
Instead of intra-oral scanners, we still use traditional alginate and PVS impressions. Instead of scanning a bite in a few seconds, we must take the time to fabricate occlusal rims or gothic pin tracers. Where dentists have a consistent and repeatable dentate bites, Denturists must coach the patients to provide the right information (sometimes more than once). Full arch restorations, whether on implants or resting on soft tissues, require larger data sets and are often more challenging. For this reason, there have been few technological advancements in the world of Denturism.
When restoring existing hybrid implant bars, we often face challenges with the amount of clearance we have to work with. During initial placement of the implants and bars, a bone reduction can create more space for the restorative elements. However, when the implants and bars are already placed, there is little that can be done. We must work with what we’ve been given and do the best we can.
Using new digital workflows and new materials, we can start to develop new solutions to old problems.
The use of digital technology and new materials in challenging situations is illustrated in this case report.
The patient presented with existing upper and lower Nobel Biocare bars and informed us that they had fractured the acrylic teeth in the posterior region more than half a dozen times! The patient was in desperate need of a long-term solution.
Upon reviewing the case and removing the fractured acrylic, we discovered only 4.93mm between the upper and lower bars. (Fig.1)
With 4.93 mm of total space to work with, we had less than 2.5 mm to work on each arch. Restoring with acrylic would have likely lead to additional failures.
By working in conjunction with Perfit Dental Solutions, their in-house CAD experts designed a wrap around structure which would fit over top of the existing bars (Fig.2).
After the design was completed and reviewed, Perfit milled the restoration in a high-end milling machine from Europe, capable of milling to 0.5 microns of accuracy to ensure quality and fit.
For the restoration, Perfit milled a material generally used for making non-metallic bars, copings, frameworks and bridge work. The material is composed of a multi-directional interlacing of fiberglass and resin in several layers. While the material is quite difficult to mill, the strength properties made it ideal. With a flexural strength of 393 MPa, we were quite confident that the restoration would not break again, even though the patient had a very strong bite.
The denture was finished with custom composite to provide a highly esthetic solution. Perfit’s in-house RDT created highly esthetic, natural looking teeth, by building up multiple layers of composites.
After completing a dry-fit to ensure proper fit, the denture was cemented in place with the referring surgeon (due to the scope of practice this can not be done by Denturists in BC). Because of the high accuracy of the design software and milling machine used, the restoration required minimal adjustments which made delivery extremely quick. Everything, from the design, milling and finishing was completed within 24 hours so the patient did not have to go without teeth for more than one night.
The patient was extremely satisfied with the restorations and shared his excitement with another patient in the lobby while leaving. (Fig. 3)
Materials such as reinforced fibre composites and PEEK materials approved for long term use (such as Pekkton) are redefining Denturism as we know it. While these materials are generally only available in millable forms, they are drastically changing the workflows as we know them. The patient benefits and practitioner benefits are significant. Denturists can now produce high end restorations in a fraction of the time.
Because the material is approved as a fixed substructure, Denturists can look at various workflows depending on the implant platform used. With Nobel, Denturists can utilize authentic bars and custom abutments to satisfy the needs of dentists / surgeons who insist on having authentic parts. If 3rd party warranties are sufficient, Denturists can create final restorations, the day of surgery. This eliminates the need for several appointments at the time of the final restoration for bar verification jigs, bar try-ins etc.
With other implant platforms such as Struamann, Denturists can deliver fully authentic permanent solution the day of surgery. No final denture is required. When the implants are fully integrated, Denturists / Surgeons remove the prosthetic and quickly add to the underside using light cure composite. The digital workflow and materials significantly reduce the amount of appointments as well as potential failures during implant integration repairing or replacing restorations. By picking the restoration up in mouth, we can also guarantee passivity.
Unlike a Zirconia, these materials are much easier to adjust in-mouth should any occlusal adjustments be required. They can easily be added to using composites and provide a much more efficient solution to an old problem.
The future of digital dentistry is exciting!
Prior to publishing the article we wanted to follow up with the patient to see how they were doing. The patient had not experienced any additional breakages or fractures. In addition, the patient advised us that they hit a fence on their snowmobile going 70km/hour that hit their face. With a bloody mouth, he was forced to walk 5km back to their house (out of cell service). He was convinced the restoration would have broken to impact, but much to his surprise the restoration had not chipped or fractured at all.
About the Author:
Laura Throupe RD is an independent registered mobile denturist in the province of British Columbia who focuses on the implementation of digital solutions, working closely with surgeons, specialists and general practitioners.