The Practical Dentist Volume 1-3; A Monthly Journal for the Dental Practitioner (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1889 Excerpt: ...then insert the gum sandrac. Here is a neat, clean method, which can be used as nicely in approximal as in crown cavities, without danger of messing the margins of the gums. When a cavity extends below the gums, and the latter projects above the edge of the roots, I apply the rubber dam; or, at least, take extra precautions against moisture, and I am sure that neither moisture gets in nor arsenic gets out.--Ed. Dom. Dent. Jour. Gold Annealing.--My apparatus for annealing consists of a tray of the finest thin sheet steel, with symmetrical indentations for holding the pellets, so that they may not come in contact with each other. Probably mica would be better for the tray, and, indeed, I have used it, but it burns out after awhile, and, besides, it can not be indented like the steel or iron sheet, and the pellets get in contact and cohere, thus causing trouble; I have, therefore, for a long time used only the iron tray. Beneath this tray is a small Bunsen burner, to which it is attached, the tube not quite as large as that of a common gas burner. The relative supply of gas and air to this is so arranged that the flame can be turned down to the smallest point. The flame which I ordinarily employ is not more than an inch high, and proportionally small, while the combustion is so nearly perfect that it is difficult to tell by sight whether or not it is lighted. It gives me an average temperature for annealing of about 700 degrees F. Some foils will anneal sufficiently at 600, while others require 800. Gold at a cherrv-red heat is about 2,000 degrees F. At the commencement of an operation the office girl fills the tray with pellets of the size which I indicate, but the gas is not yet lighted. The base of the filling and the larger part of its body, unless it be t...