discs with milled removable dentures

Digital Denture Evolution: CAD-CAM and 3D Printed Dentures

In recent years, technological advances have facilitated the development of Computer Aided Design and Manufacturing (CAD/CAM). However, removable denture design has used the same procedures for more than fifty years. The complete removable denture procedure was the last method practiced before switching to digital technology. Although several systems are now available and have been described in the literature, their usage by dental practitioners and/or technicians remains marginal on a daily basis.

patient with missing upper and lower teeth

Fig.1

We’ll describe the case of a 59 years old patient whom we rehabilitated with alternative options offered by 3D printer systems, with a very new digital workflow and by CAD/CAM Complete Removable Denture systems.

hopeless dentition with periodontitis

Fig.2

His dentition was hopeless, so we decided to extract all remaining teeth, and to rehabilitate the patient with a plan two maxillary immediate complete dentures.

digital denture project

Fig.3

Immediate dentures offer many advantages:
– Preservation and/or restoration of aesthetics
– Preservation of masticatory and phonatory functions
– Preservation and/or restoration of the vertical dimension
– Bone preservation
– Surgical wound protection

digital impression of edentulous arch

Fig.4

Digital impressions were taken and virtual extractions were performed.

digital impression with extraction simulation

Fig.5

We used a software to design the dentures according to anatomy, aesthetics and phonetic parameters.

digital complete denture project

Fig.6

Once the design is finalized, the project files are sent to the 3D printing machine.

3D printed provisional dentures

Fig.7

The 3D printer can print both the artificial teeth and the pink denture base.

digital impression palate and folds details

Fig.8

New technologies allow us to copy many anatomical details, such as transverse palatine folds and the incisal papilla, which can then be transferred into the design of the new digital denture.

provisional complete denture

Fig.9

The complete provisional denture is now ready.

3D printed complete removable dentures

Fig.10

The two 3D printed immediate dentures.

post extraction suture

Fig.11

On the second appointment we extracted all the hopeless teeth.

complete provisional dentures

Fig.12

So we gave the patient the immediate 3D printed dentures.

smiling denture patient

Fig.13

As you can see, we got a good esthetic result and restored phonetics and function.

mock-up denture as custom impression tray

Fig.14

After the two-month healing time, we relined the dentures and then scanned them to 3D print the copies of the provisional dentures which we used as custom trays for the precision impression.

precision impression for complete denture with closed mouth technique

Fig.15

We took the final impression with PVS materials, according to the closed mouth impression technique. The inter-arch relationship could be recorded in the same session with an elastomer (silicone bite registration).

complete digital denture project

Fig.16

We scanned the functional impression to obtain the virtual working models.

CAD for complete digital denture

Fig.17

These models are placed on the virtual articulator and the reference points are identified (incisal papilla, canine tooth tips, retro-molar pad centers, limit of the retro-molar pads, tuberosities, etc.) to trace a schematic representation of the pound area to correctly place the posterior teeth.

digitally designed complete upper and lower dentures

Fig.18

Then, the limit of the future denture base is drawn and a dental setting is proposed by the software. The software contains a library of teeth of different brands and shapes and a function with an automatic proportional size table between the anterior and posterior teeth.

discs with milled removable dentures

Fig.19

The denture base extrados is milled out of a pink resin disc with specific alveoli for the prosthetic teeth. The artificial teeth are then milled from a white resin disc, and will be later bonded onto the pink base. The denture base intrados will be milled after teeth are bonded. Note that, if one of the teeth interferes with the virtual model, the machine will mill it to correct the shape.

CAM digital denture before finishing

Fig.20

The dentures were removed from the disc, scraped and polished according to the conventional procedure.

final digitally designed and fabricated dentures

Fig.21

Final dentures ready for delivery.

before and after complete denture rehabilitation

Fig.22

The final result was very satisfactory. We transferred all the information obtained from the temporary-immediate restorations to the final rehabilitation, and the patient is happy.

Conclusions

Technology has given us today digital denture design softwares that can really help standardize clinical results, thus improving our current workflow. Learning about this tools now will help develop better ones for the future.

Bibliography

Bonnet G, Batisse C, Bessadet M, Nicolas E, Veyrune JL. A new digital denture procedure: a first practitioners appraisal. BMC Oral Health. 2017; 17: 155.

Hobrink J, Zarb GA, Bolender CL, Eckert S, Jacob R, Fenton A, Mericske-Stern R. Prosthodontic Treatment for Edentulous Patients: Complete Dentures and Implant-Supported Prostheses. St.Louis: Elsevier Health Sciences – Mosby, 2003.

Osnes CA, Wu J, Venezia P, Ferrari M, Keeling AJ. Full arch precision of six intraoral scanners in vitro. J Prosth Res. 2019 Venezia P, Torsello F, D’Amato S, Cavalcanti R. Digital cross-mounting: A new opportunity in prosthetic dentistry. Quintessence Int. 2017;48(9):701-709.

Venezia P, Lacasella P, Cordaro L, Torsello F, Cavalcanti R. The BARI technique: a new approach to immediate loading. Int J Esthet Dent. 2015 Autumn;10(3):428-43.