US2862298A

US2862298A - Dental grinding means

Info

Publication number: US2862298A
Application number: US339088A
Authority: US
Inventors: Weigele Bruno
Original assignee: Individual
Current assignee: Individual
Priority date: 1952-02-26
Filing date: 1953-02-26
Publication date: 1958-12-02
Anticipated expiration: 1975-12-02

Description

Dec. 2, 1958 B, WEIGELE DENTAL GRINDING MEANS Filed Feb. 26. 1953 &

2 4 2 I 4 in United States Patent DENTAL GRINDING MEANS Bruno Weigele, Frankfurt am Main, Germany Application February 26, 1953, Serial No. 339,088

Claims priority, application Germany February 26, 1952 1 Claim. (Cl. 32-58) The invention relates to the grinding of teeth for the fitting of a prosthetic part, such as for example, a jacket crown, three-quarter crown or the like, in the mouth of the patient by using a grinding band, wherein the tooth undergoing treatment serves as a tensioning element for the grinding band.

The invention has as an object the task of making it possible for the dentist to achieve an accurate grinding, both with respect to a specific surface quality and to geometrical shape, such as was not possible with known rotating grinding bodies which have hitherto been used. The abrasive action of the rotating grinding bodies which are now used is only intermittent, and corners and edges can remain which are disadvantageous to the finished work. This may, for example, lead to a break when jacket crowns of porcelain are being fitted and, with metal crowns, projecting corners are left. Crown rims which project cause, however, chronic inflammation of the gums (paradentosis) and caries in the rim of the tooth. On the exactitude of the edge finish in tooth workings, there depends in turn the fineness of the cement joint; the finer the joint is, the longer the life of the repair work will be.

The invention provides for employing a readily usable flexible strip band of paper, linen, metal, wire cloth or the like, provided with an abrasive coating, the free ends of the said strip band being provided with securing members, such as for instance, metal bushes; the band may be coupled, bent in a semi-circular looped shape, to a dental hand-piece by means of which the grinding band, acting as a loop for carrying out the grinding work, is set in reciprocating movement along a semi-circular path. This strip band, the ends of which are provided with securing members, may either be fashioned as a straight strip or as a strip having a more or less strongly marked angular shape.

It is known to use, for grinding work, strips of paper, linen or metal provided with a grinding surface which strips are held and guided manually and are moved to and fro in the spaces between teeth such as, for example, for the purposes of polishing tooth fillings.

A device is also known for the same purpose by means of which a strip-shaped grinding band is reciprocated mechanically. With both the known grinding bands formed as strips, a controlled grinding such as provided by the invention is, however, not possible and is also not intended, as the use thereof should and can only be to polish fillings at the contact surfaces of the teeth.

Finally, for grinding tooth stumps in a patients mouth, a device was proposed with which it was planned that the grinding should be carried out by rotating an endless grinding band. This band is set in rotational movement by a toothed-wheel gearing enclosed in a housing; it is tensioned about guide rolls and is adapted to be arranged about the tooth stump, which serves as a tensioning element. This device, however, has not been introduced into practice, for owing to its size, i. e. owing to lack of space in the patients mouth, it cannot be put into use, and it also does not make it possible to work from all sides on the tooth undergoing treatment. Rotating grinding bodies have therefore remained in use up to the present for the work described in the foregoing.

As compared with the aforesaid proposed devices, the use of a strip band bent in the form of a semi-circle, which is the basis of the present invention, gives in the final finish in conjunction with the surface contacting the tooth stump to be treated an exact rim finish such as could' never be achieved with present methods of grinding. In the preparation of a jacket crown and three-quarter crown, there is considerable difficulty in the finishing of the two adjacent side surfaces on the 'success of which finishing the later quality of the preparation depends.

The use of a looped shape strip band makes possible the surface treatment of three sides of a tooth simultaneously, and the said tooth surfaces are, according to the invention, necessarily or to some extent automatically ground in a parallel manner. Such treatment has hitherto been dependent on the visual judgment of the dentist. Moreover, the simultaneous treatment of three side surfaces of a tooth has the great advantage of saving a considerable amount of time as compared with the hitherto customary grinding method using rotating grinding bodies, with which only one surface or side of a tooth could be treated at a time.

The use of a grinding band according to the invention has a further great advantage in that the elastic grinding band makes scarcely any noise. In contrast thereto, a grinding method using rotating grinding bodies is accompanied by a noise which is agonizing and almost unbearable and makes many dentists shorten the grinding process at the expense of the accuracy of their work. Moreover, it is much more pleasant for a patient if the grinding process is carried out with the grinding band according to the invention, for the patient does not have to keep his mouth Wide open, as was necessary with the hitherto employed grinding means.

The grinding band according to the invention is shown in various constructional forms in the drawing, which also shows the manner in which the said grinding band is used:

Figure 1 shows part of a set of teeth with a ground tooth stump,

Figure 2 shows a ground tooth stump for the fitting of a three-quarter .crown,

Figure 3 is a View of a strip band fashioned with a markedly angular shape,

Figure 4 is a view of a strip band bent at a small angle,

Figure 5 is a side view of Figure 4,

Figure 6 is a side view of the strip band in a looped shape,

Figure 7 shows the connection of the strip 'band to a dental hand-piece,

Figure 8 is a view in the direction of the arrow X of Figure 7,

Figure 9 shows a further connection of the strip band to a dental hand-piece, and

Figure 10 is a view of the arrangement of the loopshaped grinding band on the dental hand-piece.

The strip band 1 consists of a flexible material, for example, linen, metal, wire cloth or the like. The strip band may be fashioned as a straight strip, but it may also, as Figures 3 and 4 show, be given an angular shape to a greater or less degree; in fact, the shape of the strip is adapted to the type of tooth which is to be ground and to the desired preparation, i. e. jacket crown, cap crown or three-quarter crown, etc. The strip bands are therefore readily adapted to the individual types of teeth. The term readily adapted should be understood as meaning that the dentist can have in stock or in readiness a number of grinding bands 1 which are suitably adapted to the various types of teeth (incisors, canine and molar teeth) and'to' the type of preparation desired, i. e. jacket crown, c'ap' crown, three quarter' crown, etc., so that depending on what tooth is to be treated the suitable band is fitted on to the dental hand-piece.

The free ends of the strip band 1 are provided'with securing members such as, for instance, metal bushes 2, by which the band, which has been looped into a semicircular shape (Figures 6, 8 and 10), may be attached to the dental hand-piece, the connection being effected by merely fitting the bushes 2, for example, over the 'fingers 4 projecting from the hand-piece 3, said fingers being set in reciprocating movement in known manner so that the band 1 is also made to reciprocate. In connection with the fingers 4, there are expediently provided several securing parts 5 (Figure 8) for the attachment of the band 1, thus alfording the possibility of compensating for the size of the tooth, that is, of altering the angle of the loop. The grinding band may also be disposed about a roll (for example, a 3, 5, or 7 mm. diameter) and secured on a pin of the said roll. The roll may expediently be provided with a groove. First the tooth is roughly ground in the usual way and then further ground in the desired manner with the grinding band according to the invention. The rounding off of the four corners of the tooth, which at present takes two-thirds of the time taken by the whole treatment process, is automatically achieved accurately and without trouble, by using the grinding band according to the invention, in one to two minutes as compared with the thirty minutes and more previously required.

. The grinding band may be used for many purposes, 351101 the separating of two teeth. The instruments at present in use for this purpose may therefore be dispensed with. The grinding band may be operated from behind (palatal or labial side) or from in front (labial or buccal side) of a row of teeth. It can be used on the front surface of the tooth and also on the rear surface; that is, it can be used on all sides. This is achieved by using a fork-shaped driving means to which the grinding band is attached by metal bushes 2.

The grinding surface layer of the band 1 may be variously chosen as regards fineness.

The use of the strip-shaped grinding band 1 according to the invention for grinding the rear surface of an incisor from the outside is shown by way of example in Figure 9.

I claim.

An instrument for efiecting an abrasive dental treatment comprising a pair of movable parts adapted for reciprocating motions in approximately parallel directions, a strip-shaped band of a flexible material, a grinding material covering at least part of said band, and bushings arranged, respectively, at the ends of said band and connected with the movable parts so as to apply to said band a reciprocating motion in the direction of said reciprocating motions of said movable parts of the dental instrument, said strip-shaped band including a portion of enlarged width and end portions extending oppositely and angularly away from the portion of enlarged width.

References Cited in the file of this patent UNITED STATES PATENTS 758,422 Crenshaw Apr. 26, 1904 1,147,594 Ball July 20, 1915 1,201,875 Russ Oct. 17, 1916 1,379,489 Taylor May 24, 1921 1,880,617 White Oct. 4, 1932