Instructions for Use
Metal Framework
The crown or bridge framework should be designed in such a way that they corre-
spond to the tooth form which is to be replaced, making sure that there are no sharp
angles or undercut areas. The recommended wall thickness for a single crown is
0.3 mm for precious alloy and 0.2 mm for non precious bonding alloy. It is also impor-
tant to avoid making the porcelain metal junction in a contact point area as this may
cause stresses at this junction. In order to achieve stability in a bridge framework cast
in precious alloy, it is recommended that the connection between the above mentio-
ned and the pontics are of metal.
Surface Treatment of the metal framework
(fig.1) It is important that the metal framework is free of porosity and casting defi-
ciencies. The metal is finished by firstly grinding all the surfaces with a tungsten car-
bide in order to obtain a clean smooth surface, secondly the surface is ground with a
porcelain bonded abrasive e. g. Shofu Lab Series Stone in pink, white or coral depen-
ding on the type of alloy being used. The framework is steam cleaned, blasted and
oxidised according the manufacturers recommendations. In most cases a single bla-
sting with Aluminium oxide after the oxide firing assures an optimal bonding to the
porcelain (fig. 2).
Paste Opaque / Powder Opaque
Conventional Powder Opaque and a new Paste Opaque are available within the
VINTAGE HALO SYSTEM. HALO Paste Opaque is ready to use and requires no mixing,
and if required it is possible to thin the paste with modelling liquid. A small amount of
paste is put onto a glass slab or dry mixing pad (fig. 3) and a thin even layer is applied
onto the dry framework with a Shofu Nylon Brush No. 5 (fig. 4). Fire according the
firing table. The fired surface should have a silky mat sheen.
Note: In order to guarantee the complete firing of the organic components
within the paste opaque it is very important that the modified drying, preheating
and firing times are followed.
VINTAGE HALO opaque powder has been refined and when mixed with the
specially developed modelling liquid gives a smooth and paste like consistency during
application. Mix the powder opaque by adding the modelling liquid to the required
consistency (fig. 5) and apply a wash layer to cover the framework (fig. 6). Fire accor-
ding to the recommended firing table. A second layer of paste or powder opaque is
applied to achieve the optimum coverage of the metal (fig. 7 + 8). Slight condensing
with a Ceramosonic condenser can increase the bond strength to the alloy and give
an even, homogeneous surface. Characterisation is often necessary in the cervical
area, this can be achieved by using the modifiers within the system, with the corre-
sponding opaque, to achieve the desired aesthetic result.
Note: Care needs to be taken to use only paste opaque with paste modifiers, and
powder opaque with powder modifiers. It is essential that pastes and powder
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