Interview with Dr Francisco X. Azpiazu-Flores

A new case series has documented the trials and use of 3D printed full shell dentures as a diagnostic tool in implant design and fabrication of temporary restoration to expedite full restoration. Dental Tribune International spoke to lead researcher Dr Francisco X. Azpiazu-Flores of the Department of Prosthodontics at the Indiana University School of Dentistry in Indianapolis, USA about how the research highlights the potential of this approach to simplify and streamline the procedure and save clinical and laboratory time, offering enhanced aesthetic and functional outcomes.

Dr. Azpiazu-Flores, what are 3D printed full dentures?
The complete denture with 3D printed shell is a diagnostic device. Its main purpose is to determine the position of the future artificial teeth in the desired vertical dimension in centric relation, all necessary elements for a successful full-body restoration with dental implants. The position of the anterior tooth is determined with the full shell denture and the position of the incisor can be digitally modified in the 3D modeling software during the design stage using intraoral and extraoral photographs as a reference or if necessary can be adjusted chairside using dental composite to achieve the aesthetic result desired by the patient. After determining these parameters and validating them intraorally, patient satisfaction should be optimal.

Can you analyze the accuracy of 3D printed shell dentures in reproducing esthetic and functional features such as incisal position, midline alignment, and occlusal plane orientation?
A complete overdenture can preserve the esthetics of the patient’s existing denture if it is adequate, and if changes to the artificial teeth are required for either functional or esthetic purposes, they can be modified digitally or in the chair. The position of the cutting edge, the orientation of the midline and the mafic plane can be adjusted by adding or removing material as needed in this diagnostic device. Since this device is only intended to help visualize and define desired prosthetic contours, the clinician can adjust extensively without concerns about adjustments affecting its long-term durability.

“It’s a simple method.”

What challenges did you face with the digital workflow when creating 3D printed shell dentures for a full arch restoration? Are there specific cosmetic considerations or adjustments that are more difficult to manage compared to traditional methods?
A potential limitation of the shell-and-plate complete denture is that if it is fabricated from a complete denture with unstable posterior occlusion or incomplete anterior tooth relationships and the clinician is unable to recognize and adjust this digital or chairside, these adverse elements they can be transferred to the full denture with a shell and then to the design of the dental implants, leading to inaccurate implant design and placement. In addition, learning how to use the computer modeling program takes time. However, most dentists these days are very familiar with using such software, so the learning time shouldn’t be too long.

How do 3D printed shell full dentures affect facial and lip support compared to the conventional method? Are there specific techniques you use to ensure optimal esthetic results for soft tissue support?
Facial and lip support are important parameters when restoring edentulous patients. Traditionally, flangeless full dentures or artificial tooth arrangements have been used to assess these parameters. With the 3D printed full denture shell, once the artificial tooth position is determined and validated intraorally, a flangeless 3D printed appliance can be created using the contours of the full denture shell teeth. This requires an additional appointment. However, it is a necessary step for the complete restoration of the upper jaw.

Is there anything else you’d like our readers to know about this case series or any other research you’re working on?
I would encourage them to try making a 3D printed shell full denture for their next full dental implant restoration! It is a simple method that will make their work easier. I also encourage them to expand the applications of this technique by adapting the device design to fit their clinical scenario!

I am currently working on other protocols to speed recovery with multiple or single implants. If readers are interested in checking them out, they can refer to mine ResearchGate profile.