The American text-book of prosthetic dentistry / in contributions by eminent authorities, edited by Charles J. Essig.

  • Essig, Charles J. (Charles James), 1841-1901.
Date:
1900
Catalogue details

Licence: Public Domain Mark

Credit: The American text-book of prosthetic dentistry / in contributions by eminent authorities, edited by Charles J. Essig. 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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    wood, 7^ inches square by 23^- inches liigh. B and C represent a sheet of rubber S^j inches s(juare by 1^ inches thick, securely fastened to the lower end of the block bv screws. This block fits into a box made of 1^- FlG inch pine boards, broader below than above (Fig. 13, D), furnished Avith a loose bottom, made of 2-incli seasoned oak or ash, and provided with four pieces of solid rubber cylinder (Fig. 12, E) 1^ inches in diameter by 2 inches long, let into it by holes of the same dimensions bored to a depth of 1^ inches. Two thicknesses of rubber are thus interposed between the block upon which the anvil rests and the floor of the laboratory, and so much of the sound due to the percussive force of the hammer is thereby dead- ened that scarcely any noise or vibration will be observed by persons in other parts of the house. The anvil (Fig. 14), which should weigh not less than 40 pounds, may be securely fastened to the block upon which it rests by strong iron staples (G), and the box or outside covering of the block reinforced by iron bands, as shown in H. A swaging block so constructed may be looked upon as a permanent piece of labor- atory furniture, and one that will not be likely to get out of order. Two swaging hammers are required—one, weighing about 2 pounds, is of much use in starting the plate. The heavier one, which should weigh b^ or 6 pounds, is used with greater force after the plate has been made to partially conform to the zinc die when there is no longer danger of its pleating or folding. Plaster-table and Sink (Fig. 15).—The work- ing of plaster, which forms so important a part of the operations of the dental laboratory, is entitled to much more care and attention than it usually receives at the hands of the mechanical dentist. It may be employed with neatness and precision, when its results become truly artistic, or, as is too often the case, it may be handled in so slovenly and untidy a manner as to greatly lower the standard of results, and, unless kept cai^efully within the precincts assigned it, cause the laboratory to become a most unattractive place. It is of importance, therefore, that a suitable table be provided upon which the casting and subsequent trimming of plaster models and other parts of the laboratory work depending upon the employment of plaster may be performed. The plaster-table should also be supplied with a sink and receptacle for the cuttings and refuse fragments. The accom- panying diagram shows such a table and sink which the author has found to be practical and convenient. It has been designed especially to protect the floor and other parts of the laboratory from contact with plaster. It is 31 inches high, 23 inches wide, and 27 inches long, and has an opening (A) 8 inches by 8 inches square, under which rests a portable box (C), 12 by 12 inches square, intended to receive all cuttings and refuse plaster. The table is provided Avith a small rest (B) for convenience in resting the model while trimming to proper dimensions. It is also provided