US2096375A - Dentist apparatus - Google Patents

Description

Oct. 19, 1937. w, JONES 2,096,375

DENTIST APPARATUS Filed May 19, 1936 INVENTOR. WZZZWJE. J BY ATTORNEY.

Patented Oct. 19, 1937 UNITED STATES PATENT iQEE 1 Claim.

This invention relatesto improvements in dentists apparatus and is directed more particularly to improvements in apparatus for use by dentists in the manufacture of false teeth and the like. It is one of the principal objects of the invention to provide a novel device whereby an accurate impression of the patients upper jaw may be readily taken without the unpleasantness and difiiculty usually present during such operations. Not only does this device make the operation easier and pleasanter for the patient but it does not tend to detract from the efiiciency of the dentist.

It is another object of the invention to provide an improved so-called impression tray which is arranged to receive the plastic material from which the impressions are commonly made and means is provided to facilitate the dentists determining in advance the amount of plastic material which will be needed to form the desired impression. That is to say, the impression tray is so formed that it may be placed into the patients mouth devoid of the impression-making material and prior to the actual impression-taking step and, by reason of the character of the device, it is possible for the dentist to then determine just how muchplastic material he will need to place in the tray.

It is one of the distinctive features of the device of the invention that excess plastic material may be conveniently taken care of and the usual danger of its overflowing or dropping into the mouth of the patient, and thus causing discomfiture and gagging and the like, is obviated.

Various other objects and advantages of the invention will become more apparent after a reading of the following description of the present preferred form thereof and reference will be had tothe accompanying drawing wherein:

Fig. 1 is a plan. view of the device of the invention;

Fig. 2 is a sectional view on the line 2--2 of Fi 1;

Fig. 3 is a sectional view on the line 33 of Fig. 1;

Fig. 4 is a sectional view on the line 44 of Fig. 1; and

Fig. 5 is a sectional view similar to Fig. 2 showing the parts in different relation.

Referring now tothe drawing more in detail, the invention will be fully described.

It is customary for the dentist, when making an impression of a patients upper jaw to place in what is called an impression tray a certain amount of an impression-taking material, such as plaster of Paris, wax, or the like, and then (in case of making the upper plate) to press this tray and its contents upwardly against the upper "jaw so that the jaw displaces some of the plastic material. It is obvious that the displaced material must go either towards the center of the tray or overflow the outer sides thereof.

Too much plastic at the center of course causes discomfort and undesirable pressure against the roof of the mouth while when the material overflows the sides of the tray it drops down into the mouth of the patient and causes gagging.

According to my invention, it is possible for the dentist to overcome these difficulties.

Furthermore, it is diflicult for even the most experienced dentist to exactly determine in ad- Vance the proper amount of plastic material which should be placed in. the tray in order to make the various shaped and sized impressions he has to make. It is perhaps safe to say that invariably the dentist finds that he either has too much plastic, which results in the above-mentioned disadvantages, or too little which means that he must start anew.

With the device of my invention, I not only provide means to overcome the disadvantages of too much plastic, but I provide means whereby the amount of plastic necessary may be determined in advance. That is to say, my device overcomes the likelihood of having too little plastic as well.

In the drawing there is shown a tray-like member having the general shape of the human jaw. It may be of various sizes and it is common to provide at least three or four sizes to accommodate the jawsof average patients.

Preferably the tray is formed of metal but this is not essential. In any event, it is desirable that the tray have a side wall 2 and a central more or less raised part 4 with what may be called a trough part 6 therebetween. The trough part 6 is for receiving the parts of the mouth from which the teeth ordinarily extend while the raised portion 4 is arranged to be disposed adjacent the roof of the mouth.

The central part 4 is provided with an opening I 2 of substantial size and this is so arranged that plastic material not needed may fall therethrough. Then hinged to the tray member as by a hinge l4, which may take various forms, is what may be called a plate member Hi.

The plate member I6 is disposed beneath the plate member and, being hinged at one end as shown, is movable downwardly and upwardly towards and away from the opening l2. In this Way, excess plastic material which happens to be urged downwardly through the opening l2, will fall onto the upper surface of the member l5. Preferably the member I6 is formed to have a central raised part and downwardly extending side parts, all as clearly shown in Fig. 3, so as to be more or less complemental to the tray member. That is to say, it is desirable that the plate member l6 be adapted to fit more or less snugly against the under side of the tray member so that plastic material passing through the opening I2 will fall onto the plate l6 and not intothe patients mouth. 7

In the operation of my device, the dentist takes the same, without first having placed impression taking plastic in the trough thereof as is usual, and moves it upwardly against the upper jaw so that the gums are disposed in the trough and, with the plate IS in its lowermost position (see Fig. 5) places his finger through the opening 12 so that the tip of his finger touches the roof of the patients mouth. Then by measuring the distance his finger extends through the opening, the dentist mayobtain an approximate esti mate of the thickness of material needed to pro vide the proper impression.

This is to be distinguished from the present method of merely placing an unknown amount of plastic on the tray and depending more or less upon luck that enough or not too little material has been used.

According to one modification of the invention, a wad of readily compressible material, indicated at 20 by dot-dash lines, may be caused to adhere to the plate l6. Then the tray may be placed in the patients mouth in the manner above described with the plate IS in the position shown in Fig. 5 and with the bottom surface of the trough 6 in proper relation to the teeth sockets. V

Whereupon the dentist may swing the plate I6 upwardly on its hinge so that the upper part of the wad 20 engages the roof of the mouth and is compressed downwardly a certain distance according to the height of the roof of the patients mouth. Then after removing the tray and the more or less compressed Wad 20, the dentist may by measuring the height of the plastic'determine quite accurately the amount of impressiontaking material he will need.

Preferably, for convenience, the tray member has a handle 8 extending forwardly thereof. It is usual to provide an opening [0 inthe outer end of this handle so that the dentist may hang the same on a hook or the like, but this does not comprise an important part of this invention.

It is desired to point out that not only may the operator place the device in the patients mouth without impression-taking material, and thus determinethe'amount of plastic needeoL'but he may also place the more or less filled tray into the mouth Without danger of gagging, or otherwise causing discomfort to, the patient; That is -While I have described the invention in great detail and with respect to a preferred form thereofgit is not desired to be limited thereto since many changes and modifications may be made therein without departing from the spirit and scope of the invention.

What it is desired to claim and secure by Letters Patent of the United States is:

As a new article of manufacture, a device of r the class described comprising in combination, a tray member provided with an opening therethrough and having a trough-like part extending around a side of said opening, aplate member hingedly connected to the under side of said tray member so as to be movable between an upper position substantially closing said opening and a lower position away from. said opening where material on said plate member may be removed from beneath said tray, and an upstanding compressible member on the upper side of saidplate member disposed so as toextend through the opening in said tray member when the plate member is in its upper position.

a WILLIAM B. JONES.

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