US2018821A - Artificial denture - Google Patents

Description

Get. 29, 1935. B. VEND 2,018,821

' ARTIFICIAL DENTURE Filed Jan. 23, 1955 a v e INVENTOR l2 V /8 I BEM/H'MIN VEND. I6 I Y BY 1 flax 66 62W 04 ATTORNEY Patented Oct. 29, 1935 UNITED STATES PATENT OFFICE ARTIFICIAL DENTURE f 4 Claims.

This invention relates to artificial dentures.

It is the present-day practice, in replacing teeth extracted from the human mouth, to use as a unit artificial tooth a construction which simulates closely the prettiest teeth of humans at the age when the teeth are the prettiest. While such shaping may be desirable esthetically, it is well-known that such teeth have sharp incisal edges, the general cross-section of the tooth being that of a V. Such teeth generally function, in the steps of mastication, more by cutting and tearing the food than by grinding it. The latter process is more accurately the procedure in the case of persons for whom such artificial dentures must generally are made up.

During movement of the jaws for mastication, it is likewise well-known that not only do the jaws move relatively to each other in a vertical direction, but there is marked lateral, and, in most cases, longitudinal movements of the jaws with relation to each other. These movements generally are not individual, but are components of a composite resultant movement of the jaws simultaneously in all directions, vertically, laterally, and longitudinally.

With artificial dentures made up from tooths-imulating members of the character previously indicated, it is quite a common result that the fine incisal edges of the teeth of the opposed jaws fail to register, slide past each other, and interlock. A rending torque upon the engaged teeth, together with a sharp separating force applied to the means in which such teeth are mounted, occurs. Furthermore, a very distressing condition has been known to occur many times when the incisal edges of the anterior teeth would become interlocked or seated, one beyond the other, in this manner, with the lingual faces of one set of anterior teeth engaged against the labial surfaces of the other set of anterior teeth, requiring that the user pry his own teeth apart.

Where plates are used as the means for retaining assembled the teeth associated with the jaw, the retention of the teeth in their settings in such plates may be effected, and further, the suction grip of the plate upon the pallet or the ridge of the jaw may be weakened or even completely destroyed, an undesirable result in either case.

The parties for whom artificial teeth are provided normally are advanced well in age; their masticating methods have changed markedly from those of the person whose teeth are actually the models for the tooth-simulating members used in such dentures. Such patients cannot be expected to change their modes of mastication overnight, where years have imbedded in them habits for which the teeth of such dentures are of practically no use. Additionally, these toothsimulating members, built along classic lines, 8"

do not lend themselves readily to the arts not only of mastication, but also to that of the dentist when he is required to install properly a denture of this type in the mouth of a patient.

It is an object of the invention to provide an artificial tooth formation for substitution for teeth removed from the mouth of a patient. such artificial substitutes to be arranged in the mouth in any well-known manner and to present a formation which has none of the defects above noted. 15

It is an object of the invention to provide for artificial tooth formations elements of construction which, while, in the case of anterior teeth, they retain the functions of the incisal edges while giving to such teeth also the grinding function, impart, to some extent, to the posterior teeth, these same functions. The tooth formations are so devised that the patient for whom they are made up may use them in exactly the same manner as he did the teeth which were removed from his mouth and for which these artificial teeth are substituted.

Grinding of the food takes place on the molars and bicuspids, but separating the food into portions to facilitate the grinding action, is, in all 30' cases, intended to be effected by the anterior teeth or canines. In the particular tooth construction here devised, each of the teeth constructions to be substituted for posterior or anterior teeth has a surface of substantial area dis- 35 posed as its occlusal surface. To conform more closely to the natural formation of the teeth, the canines or anterior teeth are made considerably narrower than the posterior teeth, but yet an area of considerable extent forms the extreme 40 outer, food-engaging face of each of the anterior teeth.

These surfaces not only tear the food, but also provide means for grinding it. Incisal edges are defined at extremities of the surfaces, these edges 45 functioning to cut through the food. In order to impart to the occlusal faces a more determined incisal function, such surfaces are inclined tov the direction of the lingual and facial surfaces of the teeth so that, for a tooth construction 'substituted for a tooth in the lower jaw, an incisal edge at the innermost portions of the teeth will be formed. To cooperate with such lower teeth, the upper tooth formations may, in like manner,

be given an inclination so that the two inclina- 66' tions of the opposed surfaces will be substantially supplementary.

When the jaws are brought together in the normal manner, the occlusal surfaces of opposed tooth formations in the two jaws will meet, face to face, and so normally rest. By such an arfaces as above described.

The pressure of opposed artificial tooth surfaces, in many of the present-day dentures, is at right angles to the direction at which the toothsimulating members extend from their supporting medium, the latter direction being but a very slight degree removed from the .vertical. In the tooth formation of this invention, the direction of pressure closely approximates the direction of projection. In the first case, the tendency to tear an individual tooth-simulating member out of its base, or the base and all away from the gums, were problems ever to be dealt with. In the latter case, the pressure can have'little or no such deleterious efiect, the teeth being pressed into their supporting base rather than being torn out of that base.

One of the great problems of a dentist is to adjust, in the case of inserted dentures, the artificial teeth constructions in such a manner that there will be perfect registration between the opposed teeth. Working directly in a patients mouth is not pleasant either to the dentist or to the patient. To reduce the necessity for such work, a number'- of different pieces of apparatus, known as. articulators, have been devised. The purpose of these apparatus is to simulate as closely as possible-in the movements of the dentures as effected mechanically, the movements of the jaws necessary for effecting the different steps of mastication.

In one case, such an articulator includes a pair of plates, merely hinged together to move relatively to' each other somewhat similarly to the movement of the jaws, the plates being adjustable to arrange the tooth formations in different positions for association with jaws of different characteristics. In another type, called the anatomical articulator, substantially all the different individual and composite relative movements of the jaws may be simulated; admittedly, no actual reproduction of these movements, for different patients, can be effected. The latter type of articulator is expensive, but most dentists find it a necessary adjunct to their practice by reason of the high degree of difficulty found in working with the first type, and the general inaccuracy in the results obtained in that case.

Even with the anatomical articulator, however, considerable difiiculty is encountered in making even the most minor adjustments in substituted dentures out of the mouth. Repeated testing on the anatomical articulator, positioning in the mouth of the patient, and, after other defects, unobserved on the previous examination, have been determined, returning the dentures again to the articulator for further testing, and so on until the dentist feels he has anticipated the needs of that patient. all this must tediously be gone through with before a denture may be passed for its first actual trial under fire". The dentist, in no case, can predict what will result when the dentures are applied for the actual ultimate function of eating. theoretical, with the hope that his patient will conform as closely as possible to the average. In many cases, these adjustments are of no avail. The patient must return for further, and. in many cases, ceaseless adjustments.

In the type of tooth construction to be described, the necessary accuracy of set-up of minute details of the construction of the artificial teeth with relation to each other and to the mouth of a particular patient is reduced to an easily controllable factor. The tooth construction itself permits the dentist, while giving all due pains to accurately positioning the artificial teeth in the dentures, to use a simple articulator in his work, being assured that the teeth will be properly associated in their relative positions. not requiring the intricate adjustments for which the anatomical articulator is required.

The invention has particular application in the caseof an edentulous mouth. In such case, where all the teeth have been removed from the mouth, the substitute members are generally incorporated into two separate dentures, removable separately from the mouth. It is in such cases that the greatest degree of difficulty is encountered by the dentist. However, with the use of the tooth formation here described, the problems of such dentures are reduced to a minimum;

Other objects of this invention will hereinafter be set forth, or will be apparent from the description and the drawing, in which are illustrated dentures embodying features of the invention.

The invention, however, is not intended to be restricted to any particular construction or arrangement of parts, or torany particular application of such construction, or to anyspecific manner of use, or to any of various details thereof herein shown and described, as the same may be modified in various particulars or be applied in many varied relations without departing from the spirit and scope of the claimed invention, the dentures and the manner of their assembly, herein illustratedand described, being merely one of various forms in which the invention might be embodied.

0n the drawing, in which the same reference characters refer to the same parts throughout, and in which are disclosed the aforesaid dentures: Fig. 1 is a perspective view of a pair of dentures, the dentures being shown as they would appear when the jaws are moved away from each other, illustrating certain details of the artificial tooth construction Fig. 2 is an enlarged transverse sectional view,

on the line 22 of Fig. 1, the opposed dentures in such case being brought directly together, and the section illustrating the construction of the anterior teeth in accordance with the invention, and their relative positioning when at rest in the mouth of a patient whose teeth normally assume an overlapping condition;

Fig. 3 is a view similarto Fig. 2, illustrating the'relation of superposed tooth members where a tip-to-tip bite is found;

Fig. 4 is an enlarged sectional view,'on the line 4-4 of Fig. 1, illustrating the construction of the posterior teeth to embody the invention; and

- Fig; 5 is a sectional view, transversely of a mouth in which dentures of the character indicated have been positioned to replace the ire-- His adjustments must remain 5 moved teeth, illustrating the movement of the dentures and the jaws retaining them with relation to each other as certain of the steps of mastication take place.

On the drawing, artificial tooth constructions ID are shown as a part of a denture I 2 intended, in this case shown, for removal from, or positioning in, association with the palate M or ridge E6 of the particular jaw for which it is prepared. The construction of plate I8 of the denture is not made a material part of tlns invention, any wellknown structure being applicable for use in that connection. The method by which tooth constructions in are mounted in the plate likewise is not a material element in this invention, and so will not be described specifically here. While the invention is shown by the association of the tooth constructions in dentures, or specifically, in the plates of removable dentures, it is to be understood that, within certain aspects and limitations, these tooth constructions may be assembled and applied in other associations where artificial tooth constructions are substituted for removed natural teeth.

The facial surfaces 2E! of the tooth constructions may be made to simulate, in curvature and other demarcations, the contouring and character of teeth in the mouths of persons at the particular age of the patient for which the particular denture is to be constructed. To a somewhat similar degree, excepting as will appear hereinafter, the lingual surfaces 22 of the tooth constructions may be contoured. However, first discussing the anterior or canine teeth, and especially, anterior teeth 24 for the lower jaw, it will be noticed that each of these teeth terminates, not in the customary fine-line incisal edge, but actually in a blunt occlusal surface 26. This surface, in one case, was made as wide as one millimeter and, in permissible cases, may be made even larger. Each top or occlusal surface ofthese anterior teeth is so shaped that it will define a cutting edge against which food, gripped between opposed teeth, will be pressed and finally out.

For certain purposes of the invention, each surface 26 is given an inclination such that it will be disposed at an angle other than a right angle to the labial and lingual surfaces of its particular anterior tooth. Preferably, this inclination is such that edge 28, at the lingual extremity of the surface, will be formed by an acute angular intersection, the edge thus becoming a sharp, upwardly projecting edge for more efficient action in cutting food.

Opposed to anterior teeth 24 are anterior teeth 30 of the upper jaw. These teeth likewise are shaped to conform closely to the appearance of the natural teeth of persons at the age of the patient. However, in spite of each tooth being given the usual curves by which a sharply defined incisal edge normally would be produced at its lower extremity, thebottom surface, otherwise known as the occlusal surface, of each of these teeth, is defined by an inclined surface 32 similar to surface 26, defining forward incisal edges 34. Preferably, surface 32 has the same inclination, that is, where surface 26 is upwardly inclined, surface 32 will likewise be upwardly inclined between the labial and lingual surfaces.

The extent of surfaces 26 and 32 is preferably such that, when jaws 36 and 38, with which the respective dentures i2 and 40 are associated, are brought together at least a considerable portion of the two surfaces will be in contact, as shown in Fig. 2. The amount of contact will be determined in accordance with the individual case as, for instance, where preceding the removal of the teeth, the patient was known to have an 'overlapping bite, anterior teeth 24 and 30 will be disposed as shown in Fig. 2, where the labial sur- IE5 faces of teeth 36 will extend in advance of the labial surfaces of teeth 24. In spite of this disposition of the teeth, the usual interengagement of labial and lingual surfaces will not be possible since the engagement of surfaces 26 and 32 will prevent movement of the teeth into that position Teeth 2d and 33, in this relationship, will be positioned so that they may ride smoothly, one set over the top of the others, and, in this way,

effect grinding of food retained between them, 168

while, at substantially the same time, such food will be pressed by surfaces 32 sharply against incisal edges 28.

Substantially the same result will be effected in the case of teeth having a tip-to-tip bite, as shown go:

in Fig. 3. In such case, while the danger of interengagement of labial and lingual surfaces is not so ever-prcsent, many of the other functions of the new construction are made effective. In each of these two cases, the angles at which surfaces 28 and 32 are disposed will be determined by the type of bite. In the case of a tip-to-tip bite, the angle is required to be flatter than in the case of the overlapping bite, as in the latter case, surfaces as of the lower anterior teeth must all be positioned for engagement by surfaces 32 of the upper anterior teeth.

Now passing to the teeth upon which the severed portions of food are masticated, that is, the

bicuspids and molars, it is to be noted that, at 3B" the new dentures, finds its course impeded and 5;

constricted by thesharp deviation at the fine-line surface-defining walls of the canines and the rounded contour of the first bicuspids.

This feeling of discomfort is not only unpleasant, but scientificially incorrect. By flattening the top surface of tooth 44, the lingual surfaces of teeth 32 and 3% may be positioned to be nearly in line with each other, and so to accommodate the tongue to a greater degree.

Posterior teeth it of the lower jaw are constructed with occlusal surfaces 48 somewhat similar to those of the teeth already described. Instead of being the flat top of the usual denture, into which fiat top there are usually cut the cusps simulating the cusps of natural teeth, the surface 59 on each tooth i5 is given an inclination similar to that of the anterior teeth. The degree of angularity maybe varied but, in such case, opposed surfaces 52 of posterior teeth 54 of the upper jaw are similarly inclined to conform 5 closely thereto. With the arrangement of the surfaces in this manner, when the jaws are brought together, all of the teeth, posterior and anterior, will seat smoothly one upon the other, out the surfaces, by their inclination, will cause 70 the dentures of the opposed jaws to find a stable position, as shown in Fig. 4.

Now with the movements of the jaw necessary for the mastication of food, with the approach of the jaws one to the other, something similar 75 to the result shown in Fig. 5 will occur. As the anterior teeth 24 and 30 come together, the downward, lateral and forward movements of the jaws will cause the teeth of the lower jaw to ride downwardly away from the teeth of the upper jaw, at the same time bringing pressure to bear against food carried on edges 28 and effecting its cutting. Likewise, this movement will result in a grinding action as the food is mauled between the opposed surfaces of the two dentures. In the grinding action resulting at the posterior teeth, the effect shown in Fig. 5 will occur. In this case, with the lateral movement of the jaws, the dentures will ride one over the other, forcing the jaws apart as the jaws move out of the normal position.

If desired, cusps 55 may be formed in surfaces 50 and 52, while surfaces 26 and 32 may likewise becut or otherwise marked with stains or similar materials to give them the appearance of natural teeth. The surfaces may be made of unglazed materials, as in natural teeth, while the facial and lingual surfaces may be formed from enamel.

It is to be noted, however, that in connection with masticating operations of the anterior teeth, there is introduced the mechanical effect of two dies coming together and effecting cutting of the food on the incisal edges. Therefore, in addition to the grinding action of two fiat surfaces, there is also present the absolute outing action at the incisal edges. The angle at which those surfaces are to be disposed, as has previously been stated, is to be determined for each individual case, but should be in the neighborhood of between five to fifteen degrees from the hori zontal.

Many other changes could be effected in the particular apparatus designed, and in the methods of operation set forth, and in specific details thereof, without substantially departing from the invention intended to be defined in the claims, the specific description herein being merely of an operative embodiment carrying out the spirit of the invention.

What is claimed as new and useful is:-

1. For an edentulous mouth substituted members for the natural teeth, the members being arranged in the mouth to simulate the appearance of the natural teeth when properly disposed in the mouth, the facial surfaces of the members being shaped to simulate the appearance of the natural teeth, the entire occlusal surface of each of the members being defined as a single decided upward inclination in, the same direction from the facial side to the lingual side of the members, the inclination of the occlusal surfaces of the members associated with the lower jaw being supplementary to the inclination of the occlusal surfaces of the members associated with the upper jaw.

2. For an edentulous mouth, substituted members for the natural teeth, the members being arranged in the mouth to simulate the appearance of the natural teeth when properly disposed in the mouth, the facial surfaces of the members being shaped to simulate the appearance of the natural teeth, the entire occlusal surface of each 5 of the members being defined as a single decided inclination in the same direction from the facial surfaces to the lingual surfaces of the members, the inclination of the occlusal surfaces of the members associated with the lower jaw being supplementary to the inclination of the occlusal surfaces of the members associated with the upper jaw, the opposed members of the opposed jaws being related to each other so that, when the members are moved toward each other, the inclined surfaces of the opposed members will be brought into contact, the inclination of the surfaces and the relation of the members being such that, on movement of the jaws laterally relative to each other andout of the normal contacted relationship, the members of the lower jaw will ride downwardly.

3. For an edentulous mouth, substitute artificial tooth formations adapted to be positioned on the walls of the mouth to cooperate with the jaws in the movement thereof in efiecting the functions of the teeth, the artificial tooth formations being arranged in bases each fitted for cooperation with a particular jaw, the artificial tooth formations at their facial and lingual surfaces being shaped to simulate the natural tooth formations, substantially the entire occlusal surface of each of the artificial tooth formations being disposed at a substantial upward inclination from the facial to the lingual surfaces, the inclined occlusal surfaces of the anterior tooth formations defining incisal edges, the surfaces, when the jaws are moved together, being brought into contact, and the inclinations of the surfaces of the upper and lower tooth formations being supplementary to each other, the occlusal surfaces of the upper tooth formations engaging immediately over the occlusal surfaces of the lower tooth formations.

4. For an edentulous mouth, substituted members for the natural teeth, the members being arranged in the mouth to simulate the appearance of the natural teeth when properly disposed in the mouth, the facial surfaces of the members being shaped to simulate the appearance of the natural teeth, the entire occlusal surface of each of the members being defined as a decided inclination continuously upwardly from the facial side to the lingual side of the members, the inclination of the occlusal surfaces of the members associated with the lower jaw being supplementary to the inclination of the occlusal surfaces of the members associated with the upper jaw, the inclined surfaces being sumcient in extent that, when the members of the opposed jaws are 00 brought together, the surfaces will seat one upon the other.

BENJAMIN VEND.

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