US1164997A - Dental amalgam. - Google Patents

Description

ca 1.164.997 SR FATE T THOMAS JAMES DAVIS, OF NEW YORK, N. Y.

"DENTAL AMALGAM.

No Drawing.

To all whom it may concern Be it known that I, THOMAS J. DAVIS, a citizen of the United States, and resident of the borough of Brooklyn, county of Kings, city and State of New York, have invented certain new and useful Improvements in Dental Amalgam, of which the following is a specification.

The object of this invention is to materially improve the general combination of metals or alloys as they are commonly termed, that are employed in dental surgery, and although it may appear that my improvement consists merely in changing the appearance of the alloy in its non-amalgamated state, I have a further object and that is to prove the presence of a finer metal such as gold in the allow used.

Usually dental alloys 01' amalgams consist of certain desirable quantities of silver, copper, zinc, and other metals such as aluminum or bismuth, the combination being determined entirely by the requirements, and in each alloy it has been customary to include a certain quantity of gold, so that the result would be a non-oxidizing metallic substance. As ordinarily formed these alloys or a malgams have the appearance gf small granuEs fog flakes of a whitish gray color possibly due to the presence of mercury by which the metals are amalgamated. In this. its common state, it is quite apparent that the presence of gold can only be determined by certain chemical tests.

It is not always possible or desirable for the dental operator to test the alloy presented to him for use, and even though the operator were to convince himself by test that a desirable quantity of gold was contained in the alloy, the lack of chemical knowledge on the part of the average patient makes it quite impossible for the operator to convince the patient of the presence of gold within the alloy.

The use of gold in dental amalgams or alloys is not merely for its appearance, in

I fact, when the alloy is amalgamated by the operator for the purpose of making it plastic just prior to its use, the mercury surrounding all of the metals, will change their color to a gray, White, or silver color, and even after the mercury has been removed by pressure and the amalgam placed in the cavity of a tooth, its appearance will continue to increase in whiteness to a definite extent, but

Specification of Letters Patent. 7 Patented Dec, 1915 Application filed December 8, 1914. Serial No. 876,085.

under no conditions has it been found to assume the brilliant gold color.

The gold is used in the amalgam for the purpose of producing atough, non-oxidizing filling and one upon which the acids of the mouth will have no effect. The gold further assists in preventing tl i e a l l oy f ro m shrinking-"away fr'onrtfie cavity, and also assists in producing the desired hardness and strength of the alloy. It may be further noted that the presence of gold also insures that the alloy will not discolor the tooth in which it is inserted. It is evident, then, that it becomes important for the operator and patient to know definitely that gold is present in the alloy, and to establish this fact, in the alloy that I produce I omit a portion of the gold from the combination of metals during the production of the base of the alloy, later adding it in a manner that will make its presence easily appreciated.

In producing my alloy I f 1 1 s e or amalgamate together certain desirable quantities, of baser metals such as, wper si l er z i ng alum inumwr other deslrable metallic substances in certain quantities to be determined by the ultimate use of the alloy.. I thg granulate or flake the alloy by filing or shaving. I then submit the alloy to a chemical action in the presence of heat, or to an,eleotrsrohemicaliaction without heat. In each of these actions pure gold is brought into close proximity with the alloy, and a surface of gold.. isi-ideposited .u-pon each igazanuleaor flake of alloy.

It is my desire that each granule or flake of the alloy shall be entirely incased Withinan envelop of gold, and to accomplish this I have found it desirable to agitate the gold and alloy during the chemical or electrochemical action. After the gold is deposited the alloy may be slightly warmed and bur- "'i1ished.* It will be apparent, however, that the warming during the burnishing will not be necessary if a purely chemical action has beiial employed for the depositing of. the} go V r v The result of my operation is the production of an alloy of a rich gold color, an alloy 4 that will not tarnish when submitted to atmospheric conditions, and one that will by its appearance prove the presence of the desirable quantity of the finer metal.

In operating with my alloy the ordinary method will be found entirely satisfactory.

strata should be" placed in the cavity and there allowed to harden asbefo-re set forth. The color, appearance, effect, and wearing qualities of my alloy will be the same as that of any high-grade alloy in which the presence of gold is an assured fact.

It will be appreciated that modifications may be made within the scope of the appended claims without departing from the principle or sacrificing the advantages of this invention.

Having-carefully and fully described my invention, what I claim and desire to secure by Letters Patent is:

l. A dental alloy subdivided into granules and a casing of non-oxidizing metal for each said granule. asand for the purpose set forth.

2. A dental amalgam consistingof metallic substances divided into granules and a metallic casing for each said granule as and for the purpose set forth.

3. A dental amalgam consisting of an alloy of metallic substances subdivided into granules, and a metallic casing for each said granule as and for the purpose set forth.

4. A dental alloy of metallic substances subdivided into granules and a casing of gold for each said granule as and for the purpose set forth.

5. A dental amalgam consisting of an al loy of metallic substances one of which is gold, said alloy being sub-divided into granules and a .sas ii saimsa or, Said rgran ule as and for the pur fidse set forth.

'Signed at borough of Manhattan, county of New York, city and State of New York, this 18th day of November, 1914.

THOMAS JAMES DAVIS. W'itnesses:

AUGUs'rUs A. Wns'r, ARTHUR PHELPS MARK.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C.