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FIG 46: Milled definitive prosthetic teeth FIG 47-48: Finalized prosthetic teeth FIG 48

FIG 49: Definitive cementation with adhesive technique FIG 50: Color proof using colored glycerins FIG 51: Preparation from the mock-up

In the following step you will draw the "Translucency”. The “Multicolor” blocks, or a series of rubber pads in order to enhance
“Copying Line”, selecting, from the master so-called “Multilayer” blocks, have a stratifi- the anatomy of each individual tooth.
model made by copying the mockup. The cation that goes from more opaque to more Another aspect to take into account is the
software, by processing the information translucent. At the design stage, it is recom- fact that the thinnest part of the prosthetic
entered, will create the virtual prosthetic mended to allocate this last area to the real- such as the cervical third, after adhesive
teeth. The digital tools that the software ization of the incisal edges of the front teeth. cementation, transfer the natural shade of the
makes available are a valuable aid to perfect In the shared clinical case, having the need prepared tooth on the surface which, for
the shape of the prosthetic teeth (Figures 41 to make veneers very thin, I selected a hybrid example in this area, being the thinner enam-
to 45). ceramic. As mentioned, yes, it is a more elas- el, it is more chromatic. To overcome this,
tic material than a ceramic feldspathic and there are tinted cements on the market
5) Choice of material and milling of pros- also offers the advantage of being marketed through which it will be possible to modulate
thetic teeth in industrially perforated CAD/CAM blocks the final color after cementation (Figures 47
The choice of material is another important for the fabrication of crowns screwed on and 48).
key point. The modern dentist who decides implants.
to take the digital path must know perfectly More specifically, I milled five multicolor 7) Adhesive cementation
the chemical-physical characteristics of the hybrid ceramic veneers, a monochrome This last phase is very delicate because, if not
materials on the market because the latter are hybrid ceramic abutment to better mask the managed correctly, could nullify the final
directly linked to the aesthetic and functional greyness of the Tbase titanium and a multi- result both from the point of view of aesthet-
result that will be achieved. If it is clear to us color hybrid ceramic crown (Figure 46). ics and function. It is good to remember that
how natural teeth react to light, considering in order to achieve optimal stability of the
aspects such as fluorescence, opalescence and 6) Finalization of prosthetic teeth prosthetics after their cementation, three fac-
translucency, our task will be to select a This point is very important as it will define tors are key:
CAD/CAM block that is best suited to the sit- the final appearance of prosthetic teeth. • Isolation of the operating field by means
uation, i.e. one that reacts to light as natural Mistakenly, in my opinion, we rely too much of the rubber dam
teeth do. on products such as glazes or super colors to • Conservative preparation
In general, my first choice is feldspathic perform surface • Evaluation of the final color
ceramics since they allow me to get results characterizations. The objective we should I will overlook the importance of the rub-
that are closer the aesthetic characteristics of aim for at this stage should not be to achieve ber dam, in as I believe that, for the reasons
natural teeth. However, in a case in which it mirrors that reflect light evenly, but the cre- already widely known and discussed by more
is necessary to mill prosthetic teeth in very ation of a surface texture capable of reflecting than twenty years, all of us clinicians will have
fine thicknesses (0.2-0.3 mm), to avoid frac- light in a different way that gives the pros- to know that adhesive cementation it must be
tures during milling and to have accurate thetic teeth a more natural appearance. performed by isolating the operating field.
margins, it is necessary to orient oneself The Micro and Macro texture of each On the contrary, I believe it is essential to
towards the choice of a hybrid ceramic con- tooth should be sculpted by designing all stress how important conservative prepara-
taining a variable percentage of resin that those microdefects that are typical of natural tion of the teeth is: the enamel on the surfaces
gives a greater elasticity. teeth and that help us to better camouflage of the prepared teeth will allow a stronger
In addition to the “Chroma” and the the prostheses. adhesion than that of dentin. For this reason,
“Value”, in the choice of material to make When I use ceramic materials, I do not use I advise you to start the preparation from the
prosthetic products intended for anterior super colors or glazes but I limit myself, after mock-up stage, creating guide grooves of 0.5
regions; it is also important to consider the sculpting the texture, to polishing them with mm depth using a calibrated cutter that

Dental Practice // November-December 2022 // Vol 18 No 6 25