A NEW LOOK FOR CAD/CAM-SUPPORTED FULL DENTURES: VITA AKZENT LC BRINGS COLOUR TO THE DIGITAL WORKFLOW. BY MARTINA ROSENBUSCH AND ANDREAS BUCHHEIMER Leave a comment

Thanks to new technological milestones, digital dentures are becoming increasingly common in laboratories. Previously, a lot of time was spent adjusting denture bases and teeth to the correct position and occlusion so that they were correctly aligned with each other, but today user-friendly and cost-effective solutions are available as part of the digital workflow. Most of us are familiar with LEGO® and marvel at how precise the individual blocks fit together. Using the digital workflow, it’s just as easy to combine the teeth and denture base, using the VITA VIONIC VIGO denture tooth, which was developed especially for the digital workflow. With its anatomical layering of dentin and incisal materials, it also offers all the aesthetic and functional benefits of a natural denture tooth. Fabricated denture teeth using additive or subtractive techniques do not yet meet these requirements, due to their increasingly monochrome and block-based fabrication.

OPEN SYSTEM, EFFICIENT FULL DENTURES

VITA VIONIC VIGO is already reduced at the base and pre-conditioned, creating an advantage. After additive or subtractive fabrication of the denture bases, the denture teeth are simply removed individually from the blister pack and bonded one by one in the sandblasted alveoli using the special VITA VIONIC BOND adhesive. Thanks to the precise and stable fit, the bond is extremely thin, clean and also saves time. Using the idealized setup selected in the design software, the denture teeth also fit each other occlusally, requiring a minimum amount of milling and resulting in dentures that can be delivered with nearly perfect teeth. Those who are already working in a digital workflow in their laboratory can use this existing hardware and software infrastructure for digital full dentures in the future. That’s because the VITA VIONIC VIGO denture tooth can be used with all standard and open CAM and 3D-printing systems, making it the key analogue component in enabling the implementation of digital prosthetics in the daily laboratory routine. Fabrication of full dentures as part of the digital workflow allows you to make greater use of hardware and software, and in turn, increases return on investment.

GINGIVAL MORPHOLOGY

The benefits of digital dentures include efficient fabrication, a good fit without delays, and in the case of loss or damage, reproduction at the touch of a button. Providing the denture base with anatomical morphology is possible in the design software in exactly the same way as using a wax knife and modelling instruments. In addition, as a single-tooth, non-block solution, VITA VIONIC VIGO already provides the necessary leeway for gingiva during virtual designing of the denture bases. However, until now, the characteristic shade effect of the labial frenulum, blood vessels, alveolar ridges and the unattached and attached gingiva, could only be reproduced with analogue craftsmanship and a brush. This is where the VITA AKZENT LC light-curing composite stains with their multi-facetted effects come into play, turning the labial shield into a canvas of creativity.

THE LABIAL SHIELD AS A CANVAS OF CREATIVITY

For micro-retentive adhesion, the labial shield was re-contoured using an acrylic bur and the corresponding area sandblasted with aluminium oxide. Finally, a brush was used to bring the monochromatic base to life in the aesthetic zone. For this purpose, VITA AKZENT LC EFFECT STAINS were used in the blue, pink, white and dark-red shade effects. To characterize the attached gingiva and the labial frenulum, a 1:1 mixture of white and dark-red was prepared on the mixing palette. This was used to gently redraw the labial frenulum, and to re-contour the shape and shade of the alveolar ridges in the area of the attached gingiva from 13 to 23. In doing so, the unattached marginal gingiva directly surrounding the cervical areas was left out to create a reddish appearance in the alveolar arches. Under the tapered alveolar process, and in particular in the concave areas of the labial shield, the mucosa was reproduced using a 1:1 mixture of dark-red and pink. Finally, veins and arteries in the oral mucosa were simulated using blue and dark-red. Intermediate curing was performed for each step using the dental curing light to ensure that the stains were fixed before applying the next substance. After the entire customized area was levelled using VITA AKZENT LC GLAZE, the denture was placed in the light furnace for final curing.

SHADE FACETS FOR HYBRID CERAMICS, POLYMERS AND COMPOSITES

With the establishment of the digital workflow, completely new indirect restoration materials have already made their way into laboratories and practices. In addition to the standard variants of ceramic materials, materials made from hybrid ceramics, such as VITA ENAMIC or cross-linked polymers and composites, are also popular because of how efficient and easy they are to process as part of the digital workflow. The light-curing composite stain system VITA AKZENT LC now enables reliable and natural reproduction of all shade facets on these materials. Thanks to their ideal viscosity, the composite stains can be applied with precise detail and pinpoint accuracy. In addition, VITA AKZENT LC CHROMA STAINS enable adaptation of the basic tooth shade in VITA classical A1–D4 and VITA SYSTEM 3D-MASTER across a large surface area. The shade of denture teeth can also be characterized if required. In doing so, it is generally also possible to use the composite stains internally in combination with veneering composite systems, such as VITA VM LC flow to create depth effects. As a result, the natural variety of colours familiar to dental technicians from ceramic stain systems is now also available when using light-curing.

VITA® and the names of the VITA products mentioned are registered trademarks of VITA Zahnfabrik H. Rauter GmbH & Co. KG, Bad Säckingen, Germany.