Creation Willi Geller Workbook - 2
BUILDING UP THE PALATAL SURFACE
As the palatal surface is still exposed ,
the relationship of the labial surface to the framework can be checked at any time .
The palatal surface is usually built - up with a layer of darker OD
( such as OD - 41 ) or an OD mixture modified with "In Nova" , which decreases in thickness toward the incisal edge .
The area around the tubercle and the bases of the marginal ridges
are built - up with dentine .
A mixture of dentine and "In Nova "( Universal modifier ) porcelains
can be used to reproduce dark , discoloured areas in the palatal fossa .
The palatal surface is then completed with enamel ,
transparent and cervical transparent porcelains .
INTERPROXIMAL OPACIOUS DENTINE
A triangular area is removed from the cervical interdental area ,
filled with opacious dentine ( preferably OD - 32 ) and then covered with the desired shade of dentine . This provides for increased light and shade stability .
The incisal edge is built - up with a mixture of enamel and dentine .
Shows the crown after building - up completely .
Shows the restoration being dried .
Firing cycle :
Pre - drying
Hold - time
580 ° C
at least 6 min .
55 ° C / min .
920 ° C , in vacuum
1 minute , in air
Shows the slight surface luster after the first dentine firing .
THE SECOND DENTINE FIRING
Assuming that the shade does not require adjusting ,
the contours should be re - built with the following porcelains :
- Shoulder area -
1/3 shoulder porcelain ,
2/3 cervical transparent porcelain ,
- body and incisal areas - CL - O .
The second dentine firing is carried out as follows :
Pre - drying : 4 minutes at 580 ° C , firing : 910 ° C , in vacuum - hold - time : 1 minute .
Shows the correct surface finish after the second dentine firing .
Discoloured zones on the tooth surface can be reproduced naturally
with " Make - Up " porcelains ( stain and glaze effect ) .
Pre - drying : 2 minutes at 600 ° C .
Glazing is carried out at 930 ° C , IN AIR and with no hold - time .
After glazing in the furnace , the surface of the crown is finished
using mechanical means .
The glaze and surface texture of the restoration can be matched
to the conditions in the mouth using rubber
polishers , sandpaper , felt wheels , pumice and Sidol .
Herausgeber/Publisher: KLEMA Dentalprodukte Ges.m.b.H., A-6812 Meiningen, Austria
Gestaltung/Design: Graphisches Zentrum Hohenems
Ⓒ 1994 by Hämmerle Druck Quintessence, A-6845 Hohenems, Austria