US644705A

US644705A - Impression-band for dentistry.

Info

Publication number: US644705A
Application number: US70507699A
Authority: US
Inventors: George Evans
Original assignee: EVANS Co
Current assignee: EVANS Co
Priority date: 1899-02-09
Filing date: 1899-02-09
Publication date: 1900-03-06
Anticipated expiration: 1917-03-06

Description

No. 644,705. Patented Mar. 6, I900. a. EVANS. IMPRESSIUN BAND FOR DENTISTRY.

(Application fild Feb. 9, 1899.)

(No Model.)

my 24 A 35561265565: xxfim flan/ Adar 26y NrrE TATES.

GEORGE EVANS, OF NElV YORK, N. Y., ASSIGNOR TO THE EVANS COMPANY, OF SAME PLACE.

IMPRESSION-BAND FOR DENTISTRY.

$PECIFIGATION forming part of Letters Patent No. 644,705, dated March 6, 1 900.

Application filed February 9, 1 899.

To ttZZ whom it may concern.-

Be it known that I, GEORGE EvANs, a citizen of the United States, residing in the city and county of New York, borough of Manhattan, State of New York, have invented certain new and useful Improvements in Impression Collars or Bands for Dentistry; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to the art of obtaining the exact shape or contour of the neck and sides of a natural tooth or the root of a tooth in connection with taking an 'impression of the tooth or root for the purpose of obtaining a die or cast on which to construct an artificial crown or gold cap or a metallic band or collar for supporting a denture. The method heretofore followed for this purpose consists in encircling and adapting a strip of annealed copper of the proper width to the form of the neck or root. The strip is then removed, the ends touched with cement,then replaced upon the neck or root, and the ends cemented to gether, forming thus a band or collar. An impression is next taken of the tooth and the impression removed with the band in position in the impression. A model made from the impression after the band or collar is removed therefrom presents the exact form or contour of the neck or root, and on this model the neck of the crown or gold cap or the metallic band or collar for supporting the denture is formed and fits the neck of the tooth or root accurately. This method is objectionable for the reason that the impressionv collars or bands have to be made by the den tist for each individual case and also because in removing the impression material from the tooth or root the impression band or collar is apt to be moved or displaced from its correct position in the impression material or to remain on the tooth or root in the mouth and not come off with the impression, as intended. This result either impairs the correctness of the impression or mold or entirely destroys it for the purpose it is intended to serve.

The object of my invention is to facilitate the work of the dentist in procuring impres- Serial No. 705,076. (No model.)

sions of the teeth or roots and to guard against impairing or destroying the impressions by the bands or collars moving or remaining on the tooth or root when the impression is 'removed.

To this end my invention consists in me tallic impression bands or collars made in graded sizes to adapt them to be fitted to the normal variations of natural teeth or roots and having on their exterior ears, lugs, or projections, formed on them or applied in any practical way.

In the accompanying drawings, Figure 1 represents an impression band or collar with the projections formed on it; Fig. 2, the same with the projection soldered on it. Fig. 3 represents the manner of applying the band or collar to the neck of a tooth; Fig. 4, the same invested with the impression material. Fig. 5 shows the impression after it is removed from the tooth and with the band or collar remaining in the impression.

Referring to the drawings, A designates the impression collar or band. It is made from a strip of thin metal-copper, for example-with the ends soldered together and shaped to the general form or contour of the neck and sides of a tooth. On the opposite sides of this collar or band, about midway between the ends, are projections 17 b, which may be formed by making parallel slits d din the sides and pressing the parts 19 between the slits outward, thus forming projections, ears,

or lugs that extend out from the surface of the side at about right angles thereto. This is the preferred method of forming these projections; but Fig. 2 shows them formed by soldering pieces of metal of the proper form and size to the sides of the band or collar. It is to be understood that I do not confine myself to any method of forming these projections. The collars or bands thus constructed are to be made in various sizes to adapt them to fit the different teeth and the normal variations in the shape and size of natural teeth, so that by proper selection the dentist can obtain one suitable to any normal case that will require but the minimum of labor and time to be expended in adapting it and fitting it to the tooth under treatment.

These articles are used in the following manner: The dentist selects one of the impression-collars of the right size, places it on the tooth B so that the projections will be on the outside and inside, (called the labial and lingual 0r palatal sides,) and fits it closely, as seen in Fig. 3. An impression is then taken of the parts with some suitable impression material E. As the impression material E is pressed over the tooth or root it is squeezed into or around the projections I) Z), which thus become embedded in the material, and when the impression hardens and is removed the collar is drawn off the tooth with it, and remaining immovable it retains the exact and correct position in the impression or mold. hen plaster or fusible metal is poured into the impression or mold after the collar is removed therefrom, the parts of the cast or die corresponding to the neck and sides of the tooth or root will have the exact shape of the neck and sides of the natural tooth or root and be properly positioned with respect to the artificial crown or denture to be mounted thereon.

I claim- As an article of manufacture a band or eollar for taking impressions of the natural teeth or roots, adapted to be mounted on the tooth or root and made to conform thereto, and havin g projections extending out from and clear of its sides whereby when plaster is flared around the band and root or tooth the projec tions become embedded therein and thus pre vent the band from becoming displaced or misplaced when the plaster impression is removed from the tooth or root, substantially as specified.

In testimony that I claim the invention above set forth I do attix my signature in pres-- ence of two witnesses.

GEORGE EVANS.

\Vitnesses:

JOHN D. FITZ GERALD, CHAS. H. DAY.