Removing Limitations

A roundtable discussion on removable prosthetics

As dentistry continues to evolve, the world of removable prosthetics is beginning to undergo a change that many feel will soon accelerate rapidly. Digital integration is becoming more viable and popular for dentures; fixed laboratories are increasingly willing and able to expand their offerings to these solutions; and the wide variety of solutions is benefiting both dentist and patient. Inside Dental Technology spoke with three dental technicians and three dentists about the changing environment.

Transition from Analog to Digital

Inside Dental Technology (IDT): For analog denture technicians, what digital denture processes would prove to be useful, time saving, and profitable if converting to digital? What imperfections in the analog process can a digital process eliminate?

Stephen Wagner, DDS: Dental professionals developing digital dentures need to integrate the new system into a traditional process and give a reason for doing it. Some protocols ignored traditional concepts—learned and validated through experience—in the early days of digital dentures and tried to cut technicians out of the process, but that became a problem because the dentists did not have the necessary specialized knowledge. Denture making still requires so much more than simply pushing a button. Since then, digital dentures have cemented the critical role of the technician.

Robert Kreyer, CDT: By removing as many variables as possible, we can produce a higher-valued product with improved consistency and efficiency. A digital process can eliminate distortion in impression materials, as well as variables in processing, investing, and boil-out steps. It can also eliminate expansion during polymerization/processing of acrylic resin. All of these variables can affect the quality of the restoration and can be eliminated if a digital workflow is used properly.

Charles Goodacre, DDS, MSD: In addition to the benefits of fewer patient visits at the beginning of the process, creating a permanent record for future use is extremely important. With traditional methods, needing to repeat the entire process can be difficult and costly, especially for denture patients who may have limited resources.

IDT: What challenges does transitioning to a digital approach present for both the dentist and technician?

Valerie Cooper, DDS, MS: Some dentists and laboratories are hesitant about a monolithic denture—I was too, initially. I thought it would not be esthetic enough for my patients. However, the more I tried it for immediate dentures, interim dentures, and certainly implant dentures, I saw that patients were extremely satisfied with it. Now, I love it.

Kreyer: The biggest challenge is changing the mindset of practitioners, especially older ones. Newer dental school graduates are “digital natives” and are more likely to adopt digital processes. Education, however, remains a significant hurdle; it is important that school curriculums include digital processes, especially for removable prosthodontics. In clinical practices, education is also critical; dentists and denturists need to know how and when to utilize analog, digital, or hybrid processes based on the variables involved and what is best for each patient and each case.

Andre Theberge, CDT: The biggest challenge is that some dentists and technicians believe that digital technology can replace analog skills and knowledge. Digital technology should only supplement a strong knowledge of removables. Additionally, some digital denture systems involve a monetary investment, whether in digital equipment or material inventory.

IDT: Who is making the transition to digital (clinician, laboratory, or both) and what are the drivers of that?

Cooper: The most important driver is the fact that no removable prosthesis is great. Both fabricating and wearing them are not easy. Digital dentures are the best solution we have now for many patients and scenarios, but it is not the same as having teeth; it's not even close. There is a really wide mix of dental professionals making the transition. Clinicians and laboratory technicians, younger and older, are just ready—anyone who likes finding better solutions.

Kreyer: Drivers for digital transition are primarily mid-sized and larger laboratories that are acquiring the technology and creating a competitive environment, including regaining market share from overseas outsourcing. Also, students and new graduates of dental schools where technology is part of the curriculum are driving change and will continue to do so in the future.

Goodacre: There are growing numbers of both clinicians and laboratories producing all or nearly all of their dentures using digital processes. Those numbers will increase at an even faster rate now that many more major manufacturers are becoming involved in this market.

IDT: What are the benefits of the different types of digital denture processes?

Kreyer: One huge differentiating factor that some processes offer is the ability to scan, analyze, and perform a complete digital diagnostic workup for a case. Presenting a case to the clinician then the patient as a complete treatment plan before the clinician even starts to work on the patient is simply impossible with a traditional workflow. This adds significant value to the denture and should be positioned in the market as a higher-value prosthesis for the patient.

Mark Williamson, CDT: I have utilized digital options for record-taking and treatment planning, and when I have compared a denture setup in wax to a printed try-in from a virtual setup, the digital version was significantly better. I then used conventional methods to process it and convert the try-in to a final denture, but I plan to start milling the final denture as soon as more options become available. Eventually, I expect 3D printing to be an even better option for in-house production.

IDT: What are the drawbacks against transitioning to digital?

Wagner: Cost, learning curve, lack of funding, and lack of impetus are among the drawbacks. It is often cost-prohibitive for small laboratories. Digital processes also currently create mostly premium dentures, but the more abundant need is for economy-level dentures. This challenge largely has not been met yet, but plenty of potential exists, especially for larger companies that can leverage their equipment to cut costs for consumers.

Williamson: Right now, digital dentures are expensive to produce, so the laboratory needs to explain the cost-benefit situation to the dentist. Also, some technicians feel handmade dentures are better, which is inevitable because we are in a transitional period. However, I have seen digital dentures and they look great—indistinguishable from traditionally fabricated dentures.

Full-Service Laboratories

IDT: What challenges does the dental industry face in meeting current and future demand with the increased numbers of edentulous patients, and will this necessitate that crown-and-bridge laboratories step in to expand services to meet this demand?

Kreyer: Crown-and-bridge technicians can open denture laboratories, and digital capabilities will provide more opportunities for these laboratories to expand their product lines. Similarly, if removable-only laboratories purchase CAM equipment for digital dentures, they will become able to expand their services to include fixed prosthetics as well. These digital developments will open the market on both ends.

Wagner: This is the natural progression for laboratories to take advantage of this new market, especially because modern crown-and-bridge laboratories seem more digitally integrated. Crown-and-bridge laboratories can make the change without needing to purchase more machinery. This opens up a huge market for them.

Cooper: I would like to see a future in which technicians are more specialized. The work of the technician is the creative aspect of interpreting what is being seen and then designing and planning for the best outcome. If I want to make a specific type of prosthesis or product, I want to be able to find a technician whose specialty is that particular product.

IDT: How are fixed laboratories addressing the need for removable restorations over implants, and what is driving this need?

Wagner: One of the problems with hybrid implant solutions has been that the materials and techniques utilized for the final product did not provide enough strength to withstand the pressures of an implant-to-base prosthesis. With a traditional denture, the base and teeth are bonded together, and this interface is where problems such as breakage and pop-offs usually occur. Digital offerings now with implant-based dentures can be monolithic and much stronger.

Kreyer: Laboratories specializing in fixed prosthetics need to be educated on workflows, anatomy, and materials for removable prosthetics. If they try to expand their offerings without this knowledge, successful outcomes will be more elusive. Those laboratories that have transitioned successfully with expanded prosthetic product lines have educated themselves internally and, in some cases, expanded their teams with complete denture specialists. Outsourcing solutions can help for components such as implant bars in the beginning.

IDT: What level of education and knowledge does a fixed technician need to appropriately fabricate a removable prosthetic, and how are fixed laboratories obtaining that?

Wagner: Corporate-funded continuing education is how many technicians and dentists learn about digital denture techniques and products. The laboratory already knows the fundamentals and is often familiar with a computerized workflow, but that workflow must change slightly for removables. Schools are starting to show interest, but the transition has been slow.

Cooper: Dentists cannot keep pace with these new developments. Technicians need to know what solutions exist, what will work best, what the cost considerations are for each option, etc, to be a specialized planner and developer of the right solution.

Theberge: New digital tools make denture fabrication a bit easier, but there will still be a significant demand in the future for technicians with a high level of specialized knowledge in removables. A technician with some basic anatomical knowledge and tooth knowledge can do a decent job with the help of these tools, but a highly skilled technician can still make a significant difference.

Various Restorative Choices

IDT: The concept of the basic removable prosthetic has evolved and expanded to treatment modalities such as implant-supported overdentures, Toronto Bridges, fixed detachables, etc. Have you added these expanded options to your portfolio of products and why?

Wagner: We have always done implant-supported overdentures, but now I feel more secure that they will not break.

Cooper: I recently started offering Conus-supported overdentures. That is a really neat technology that solves a lot of issues with fixed hybrids as an alternative.

Kreyer: The success of a fixed or removable prosthesis really depends on the variables involved and which product(s) are selected. Combining a conversion denture that is digitally made for implant prosthetics opens up a whole new world, but there's a risk of breakage and pop-offs after the implant has been loaded with temporary cylinders. A fully milled or even printed prosthesis is one solid piece of acrylic resin that will not break or delaminate as easily. Patients want esthetics, functionality, and durability; monolithic restorations are often the best way to satisfy those needs where minimal prosthetic space exists for teeth, base, and bar.

IDT: How do these new treatment options benefit the patient?

Wagner: The patient gets a better fit and less breakage in fewer visits, and the dentures are equally esthetic. They are really exquisite; just a really high-quality product. Fewer adjustments seem to be required, though currently that is anecdotal and not yet supported by research. The denser material is not porous and thus is easier to keep hygienic. Digital dentures are easier and cheaper to replace too.

Williamson: The number of trained removables technicians in the US is dwindling. The ability to accurately scan models, create a virtual setup, and print or mill the final prosthetic allows more laboratories to provide the patient with the best possible options and the best overall experience.

IDT: How do these removable restorative options elevate the treatment protocol for the patient, clinician, and laboratory?

Kreyer: The digital removable protocol elevates diagnostics. This is the biggest differentiating factor between the digital and analog worlds. Scanning the oral environment and using the resulting data to analyze the prosthetic space and plan a case completely before even starting treatment is a huge differentiating factor between digital and analog. In my opinion, digital diagnostics have a greater impact than digital dentures. We should be doing a diagnostic workup on the existing prosthesis the patient is wearing, and analyze pictures and scans in trying to learn what the patient likes and does not like about the current dentures. Then we apply this knowledge to how we plan. Additionally, a dentist can order a CBCT scan to obtain a more complete picture of the patient's mouth, then use the STL file to make a prosthesis. After the denture is delivered then adjusted, and the patient is satisfied, that final prosthesis should be scanned and become part of the patient's record.

Williamson: Dentists and patients will definitely get a better product, especially as the software offerings continue to evolve to allow for laboratories to offer even more restorative options.

Editor's Note: Comprehensive education on removable prosthetics will be available at the 2018 IDT International Digital Denture Symposium in Phoenix, Arizona (see the Symposium Update).

About the Panelists

Valerie Cooper, DDS, MS
Private Practice
Dayton, OH

Charles Goodacre, DDS, MSD
Distinguished Professor, Restorative Dentistry
Loma Linda University
Loma Linda, CA

Robert Kreyer, CDT
Owner
Kreyer Prosthetic Consulting
San Ramon, CA

Andre Theberge, CDT
General Manager/Ceramist
Drake Precision Dental Laboratory
Charlotte, NC

Stephen Wagner, DDS
Private Practice
Albuquerque, NM

Mark Williamson, CDT
Senior Technical Manager – Removable & Implants
Ottawa Dental Laboratory
Ottawa, IL