Principles and practice of crowning teeth : a practical, systematic and modern treatise upon the requirements and technique of artificial crown work, including some incidental reference to bridgework. With 459 illustrations / By Hart J. Goslee.

  • Goslee, Hart J., 1871-1930.
Date:
1903
Catalogue details

Licence: Public Domain Mark

Credit: Principles and practice of crowning teeth : a practical, systematic and modern treatise upon the requirements and technique of artificial crown work, including some incidental reference to bridgework. With 459 illustrations / By Hart J. Goslee. 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.

    29/312 (page 17)
    Gold and platinum alloy is indicated wherever Gold additional strength and springy elasticity are desired, and PIcltinutn. such as clasps, and for stiffening the work over jjarts which will be subjected to more than ordinary stress, which property the addition of platinum, one part in 24, imparts to the alloy. The following formula is used for the purpose: Pure gold, 20 parts Pure copper. 2 Pure silver, I part. Platinum, I Platinized gold is a form of plate made by fusing Platinized Gold. pure gold over one surface of platinum, which upon being passed through the rollers then ])resents a smooth, unbroken surface of each metal. It is much used in gold work where infusibility seems desirable, and the presentation of a sur- face of gold preferable to that of platinum. It is also frequently useful as a backing for porcelain facings because of the advantage of control- ling or preserving the color by placing next to the porcelain whichever surface may cause the least, or produce the most desirable, change. Solders. The advent of porcelain work and the use of Platinum Solder. high fusing bodies has created a demand for a solder more infusible than pure gold, which was previously used for the purpose, in order that joints so made would not be affected by the high degree of heat necessary to fuse or vitrify the body. If there is absolute contact of the parts to be united, pure gold can be successfully used, because if thoroughly and sufficiently fused, it be- comes an integral part of the platinum by alloying with it; but in ex- tensive work platinum solders are an advantage because of overcoming the possibility of a change in the relation of the parts, caused by the shrinkage of the porcelain, which is considerable. Such solders are now prepared for the purpose, ranging from 10 to 40 per cent of platinum in combination with gold, but less than 20 per cent is of no advantage, and more than 25 per cent is unnecessary. They may be easily compounded by thoroughly fusing the gold and then feeding into the molten mass the desired proportion of platinum in foil or ribbon form, after which it should be hammered out and remelted several times to insure a thorough admixture.