Notes on dental porcelain : a practical treatise especially devoted to the interests of the beginner.

  • Gilbert, V. Walter.
Date:
1906
Catalogue details

Licence: Public Domain Mark

Credit: Notes on dental porcelain : a practical treatise especially devoted to the interests of the beginner. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    porcelain, for such is not the case. There are sev- eral other methods, among which can be mentioned Another the following: The method of ascertain- Method ing by experiment just what temperature and what time is required to glaze a given porcelain, and then pursue the following detail: Keep the tem- perature in the muffle at the desired figure by shift- ing the lever of the rheostat; place the porcelain to be glazed in the muffle—this will cause the tempera- ture to drop many degrees, but it is soon brought back to the desired degree—and allow a given amount of time to elapse, then open the door of the muffle and remove the work. For example: To glaze a crown made of The S. S. White Dental Manufacturing Company's High-Fus- ing Porcelain, raise the temperature in the muffle to at least 2300° F., place the crown (which should be free from all moisture) in the muffle, close the door, watch the pyrometer, and when the indicator regis- ters 2300° F., take an account of the time, keeping the pyrometer at 2300° F., and allow one- and one- half minutes to pass, after which immediately re- move the crown. Different bulks of porcelain will re- quire different lengths of time, but this variation in time is readily ascertained by experiment. First Method Of the two methods above suggested for Preferable the use of the pyrometer and furnace, the first is preferable—first, because it caters to the pe- culiar characteristics of porcelain, and second, it is better adapted to the practical working methods of the dentist. Generally speaking, all dental porcelains should be gradually heated from the room-tempera- ture to the temperature required to produce the glaze; in fact, some must be treated in this way in order to insiii-e form and color. The method first