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.

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.

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.

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

Fig.4
Digital impressions were taken and virtual extractions were performed.

Fig.5
We used a software to design the dentures according to anatomy, aesthetics and phonetic parameters.

Fig.6
Once the design is finalized, the project files are sent to the 3D printing machine.

Fig.7
The 3D printer can print both the artificial teeth and the pink denture base.

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.

Fig.9
The complete provisional denture is now ready.

Fig.10
The two 3D printed immediate dentures.

Fig.11
On the second appointment we extracted all the hopeless teeth.

Fig.12
So we gave the patient the immediate 3D printed dentures.

Fig.13
As you can see, we got a good esthetic result and restored phonetics and function.

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.

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).

Fig.16
We scanned the functional impression to obtain the virtual working models.

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.

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.

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.

Fig.20
The dentures were removed from the disc, scraped and polished according to the conventional procedure.

Fig.21
Final dentures ready for delivery.

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.
Conclusion
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
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