US3768165A

US3768165A - Denture

Info

Publication number: US3768165A
Application number: US00259808A
Authority: US
Inventors: A Nielsen
Original assignee: Individual
Current assignee: SHELLBACK MANUFACTURING Co
Priority date: 1972-06-05
Filing date: 1972-06-05
Publication date: 1973-10-30
Anticipated expiration: 1990-10-30
Also published as: CA983742A

Abstract

The basic plate portion proper of a full-mouth denture is molded in the usual manner for mating engagement over buccal, lingual and corresponding frontal gum surfaces of the patient''s jaw; and around the arch of said plate portion it is specially molded on its mating interior. In this respect said interior will in all cases afford one or more partial depth depressions which mate precisely with the remaining stub of a partially worn or otherwise physically damaged natural tooth or teeth. Optionally, the molding of the plate portion may be such as to fit nicely with a surface of the gum at which there may have been a tooth extraction at one or more locations, as well as to afford an appropriate opening or openings to matingly receive one or more sound and undamaged full-height or permanently capped teeth, so that the basic plate portion is fully mated to the jaw about the entire dental arch. At spaces corresponding to the locations of the worn tooth stubs, tooth members simulating in appearance that of the originals of the stubs are molded to the exterior of the basic denture plate portion; being backed by solid grinder formations which are also rigidly bonded to correspondingly shaped surfaces of said basic portion. These formations lie in direct vertical register with tooth stubs, so that masticating force is transmitted therethrough directly from the jaw. The replacement tooth shell components are thus located a trifle laterally outwardly of the grinder portions or formations, hence of the existing tooth stubs for which they substitute; and the arrangement of such shells in relation to other tooth parts of the denture and/or undamaged teeth in the mouth is such as to afford a natural-appearing tooth array all around the dental arch. In instances in which there has been an extraction and no tooth stub is present, the denture mates fully about the gum alone, and in this zone a fully sized and shaped replacement tooth portion is bonded to the plate portion. Otherwise, the stub-engaging portions of the plate anchor the latter to the jaw, the plate similarly anchors to existing undamaged teeth, and migration of any such tooth, damaged or not, is prevented.

Description

United States Patent 1 Nielsen et al.

[ Oct. 30,1973

[ DENTURE [76] lnventor: Axel L. Nielsen, 1316 East Elza,

Hazel Park, Mich.

[22] Filed: June 5,1972 21 Appl.No.:259, 808

[52] US. Cl. 32/17 Primary ExaminerLouis G. Mancene Assistant Examiner-J. Q. Lever Attorney-Franklin E. Quale and Franklin E. Quale [57] ABSTRACT The basic plate portion proper of a full-mouth denture is molded in the usual manner for mating engagement over buccal, lingual and corresponding frontal gum surfaces of the patients jaw; and around the arch of said plate portion it is specially molded on its mating v interior. In this respect said interiorwill in all cases afford one or more partial depth depressions which' mate precisely with the remaining stub of a partially worn or otherwise physically damaged natural tooth or teeth. Optionally, the molding of the plate portion may be such as to fit nicely with a surface. of the gum at which there may have been a tooth extraction at one or more locations, as well as to afford an appropriate opening or openings to matingly receive one or more sound and undamaged full-height or permanently capped teeth, so that the basic plate portion is fully mated to the jaw about the entire dental arch. At spaces corresponding to the locations of the worn tooth stubs, tooth members simulating in appearance that of the originals of the stubs are molded to the exterior of the basic denture plate portion; being backed by solid grinder formations which are also rigidly bonded to correspondingly shaped surfaces of said basic portion. These formations lie in direct vertical register with tooth stubs, so that masticating force is transmitted therethrough directly from the jaw. The replacement tooth shell components are thus located a trifle laterally outwardly of the grinder portions or formations, hence of the existing tooth stubs for which they substitute; and the arrangement of such shells in relation to other tooth parts of the denture and/or undamaged teeth in the mouth is such as to afford a natural-appearing tooth array all around the dental arch. In instances in which there has been an extrac tion and no tooth stub is present, the denture mates fully about the gum alone, and in this zone a fully sized and shaped replacement tooth portion is bonded to the plate portion. Otherwise, the stub-engaging portions of the plate anchor the latter to the jaw, the plate similarly anchors to existing undamaged teeth, and migration of any such tooth, damaged or not, is prevented.

11 Claims, 11 Drawing Figures PAIENlEnuclaolsn 3.768.165

saw lUF 2 PATENTED UB1 30 I973 SHEE am: 2

DENTURE BACKGROUND OF THE INVENTION 1. Field of the Invention The invention is obviously applicable to the field of dental prosthetics, but more particularly and exclusively to'a segment of that field, substantially unexplored as of this date, which concerns a full-mouth denture not necessarily preceeded, in its fitting to and wear by the patient, by an extraction of teeth.

2. Description of the Prior Art A search has revealed the following patents:

Throckmorton, US. Pat. No. 365,764, June 28, 1887 Charles, US. Pat. No. 1,104,290, July 21, 1914 Rose, US. Pat. No. 1,425,055, Aug. 8, 1922 Of these, Charles discloses a clasp-equipped partial plate type of attachment compensating for a partial mal-articulation or occlusion of teeth in a single molar tooth zone, which attachment has no direct engagement whatsoever with the patients gum, claspanchoring as it does to a single tooth only. Throckmorton shows full or partial plate dentures contemplating application to a patient to replace extracted teeth, not to matingly fit damaged or stub teeth. Rose discloses a dental crown device entailing a grinding preparation of certain teeth, and also in no wise having fitting engagement over and about a patients gum.

SUMMARY OF THE INVENTION Many elderly people, having lost some of their upper or lower teeth, still retain other natural teeth which, although not perfect, are worn or otherwise physically damaged (as for example by the breaking off of a crown or natural tooth part) to the extent they have only a fraction of their length at the time of the persons youth and prime. In many cases, indeed, such remaining teeth are periodontally strong in root, solid and healthy. Yet, the majority of dentists, in order to restore a full masticating occlusion, will proceed with a full jaw extraction and replacement by a conventional denture, whereas appropriate curative treatment, save in case of bad decay or fracture, or an impacted wisdom toot, would have sufficed. Still, this would neither afford the desired perfectocclusion nor (as an important consideration in practically all instances) improve the matter in the factor of appearance.

Experience has shown that in cases of simple tooth wear or similar physical damage, such as are instanced in the preceding paragraph, the pulp merely recedes slowly in the worn tooth, continuing to keep the tooth alive and functional, however, this condition of its na; ture makes for an increased 'masticative movement of the lower jaw in moving the extra distance to compensate for the now shorter teeth; this is over'and above the fact that the shorter teeth have an impaired occlusion.

As an example, if every other tooth in a jaw has been lost and the remaining teeth have been worn (which follows because said remaining teeth must do all the masticating), a by no means rare situation has arisen which the present improved denture is ideally suited to meet. It opens up the bite of the jaw and restores the jaw movement of the person before the teeth were worn. A method and means are proposed whereby the condition is corrected in many cases without requiring any extraction of teeth before the artificial plate of the improvement is applied, and this applies equally to both upper and lower jaws, although an embodiment dealing with only the upper is illustrated herein.

In practice the practitioner or technician merely takes an impression of the mouth, perhaps first waxing in such crooked teeth as would tend to cause a back draft to the impression, and the dental technician, makes a denture to mate to the gums, and also over the remaining damaged and undamaged teeth. In place of a missing tooth that space is filled in the ordinary fashion by a full corresponding replacement tooth of the denture, which in this spot would be supported through the plate portion proper only by the gum. Said corresponding tooth would be a commercially made one as used in conventional artificial dentures.

But assuming a natural tooth next to this extraction is still in place but worn, the denture is molded whereby this periodontally sound tooth stub is surrounded entirely on three or four exposed sides, as the case may be, by the plate portion proper, as internally molded to provide a depression to mate on the stub; and in order that such externally masked stub have a natural appearance, an aesthetic substitute there is inserted on the outside of the denture. This is in the form of a thin shell reproducing the appearance of white tooth enamel.

An acrylic or other rigid, tough synthetic resin is preferably used, being made by the technician and ap' plied to and becoming a permanent part of the denture before such denture is boiled or cured and, since the actual masticating will take place slightly inside this shell, it need not be of much thickness. It is important only that in the front of the mouth the replacement have a tooth-like appearance. As an alternative, the shell can be made by grinding a commercially available porcelain tooth corresponding to the covered natural tooth stub, to pose as a replacement therefor.

In a case where one or more teeth are longer, undamaged and/or less worn than others, one or more corresponding openings are molded in the denture, allowing such teeth to protrude through the latter and continue to act as direct actual masticators. This will further restrict lateral movement of'denture under the normal trend consequent to an extraction. In the rare but possible instancethat teeth are not entirely missing but all are worn, the procedure would be to make a denture with all shell-faced teeth; it is possible that as the art develops that such thin tooth shells will become commercially available and not require particular individual molding or grinding.

Despite the height compensation for the stubs, the overall requisite bite opening is increased no more than one-eighth inch or so.

Experience has also shown that this improved type of denture, locating and anchoring on sound teeth and gums, need not cover the entire roof of the mouth, as in the usual plain gum dentures; it remains in its anchored position nevertheless.

In brief, many people, especially middle-aged or older, have worn teeth and lost molars, yet continue to use teeth that are no longer even 50 percent effective. This must in most cases be because of a deep fear of having teeth extracted; in turn, possibly, on account of earlier pain, jaw bone or nerve trauma suffered as the result thereof. While there are people who have teeth destroyed by gum disease, in which cases extraction is proper and my remedy would not apply, there remain a very great number who would be benefitted by the improved denture.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary front elevational view of a conventional dental impression as molded from a matrix, in turn molded to the upper jaw portion of a typcial patients mouth;

FIG. 2 is a plan view showing a portion of the same impression as viewed from below;

FIG. 3 is a top plan view showing the plate portion proper of the improved denture as molded from the impression of FIGS. 1 and 2, indicating the presence, in addition to indentations formed by stub teeth members, of openings corresponding to and accommodating undamaged teeth, and blank areas corresponding to locations of tooth extractions;

FIG. 3A is a view very similar to FIG. 3, but indicating but a single tooth accommodating opening;

FIG. 4 is a front elevational view of the completed denture, prior to application to the patients mouth;

FIG. 5 is a view corresponding to FIG. 4, but with the denture schematically shown as applied to the upper jaw to complement of operational natural teeth;

FIGS. 6, 7 and 8 are respectively, enlarged scale fragmentary views in vertical section on lines corresponding to lines 6-6, 7-7 and 88 of FIG. 5;

FIG. 9 is a fragmentary side elevational view of the denture as applied to the jaw; and

FIG. 10 is a fragmentary view in section on a line corresponding to line ll0 of FIG. 9.

DESCRIPTION OF A PREFERRED EMBODIMENT A description of the denture or dental plate of the invention is clarified by a brief description of the condition of the jaw (herein assumed to be the upper jaw) of the individual for whom the denture is designed and fitted.

This condition, in turn, can conventionally be depicted in reference to the entirely conventional rigid plastic impression, shown in FIGS. 1 and 2 and generally designated 1, on which the material of the plate portion of the denture is actually molded. Thus, the patients dental impression 1, and jaw it in effect depicts (hence is considered to be correspondingly numbered) has a gum portion 2 from which extend three incisors 3 which are badly worn to a length of perhaps one-half or less of their unimpaired length, the fourth incisor having been extracted to leave a vacant gum space 4. Two canines or cuspids 5, also more or-less worn, are shown, as well as undamaged or capped premolars or bicuspids 6, all four molars having been extracted to' leave the exposed rear gum portions 7. This type of tooth and non-tooth relationship is typical of one apt to exist in the mouth ofa person of adult years, and represents a condition ideally dealt with and corrected by the improved denture of the invention, which is generally designated by the reference numeral 10.

Denture 10, as illustrated in FIGS. 3, 4, and 9 (FIGS. 6, 7, 8 and being enlarged scale individual sections), includes a plate portion proper 12 of an appropriately colored synthetic plastic, such as an acrylic, as molded to the impression 1. As the result it exhibits individual indentations or depressions 13 of variable depth, corresponding to the worn incisor stubs 3 of the jaw, also a blank area 14 as mated to the open gum space 4 of the impression I and jaw, and a pair of depressions 15 corresponding in depth to the remaining height of the canines 5. Openings 16 are depicted as formed at the full height, undamaged or capped remaining bicuspids 6 of the impression I and jaw. The remaining end portions 17 of the arch of denture 10 are formed blank and smooth to mate directly to the corresponding vacant molar zones 7. For the reason indicated above, the improved denture 10 is in a U-shape in plan between the respective pairs of lingual surfaces 18 and buccal surfaces 19; these mate substantially over corresponding gum surfaces of the mouth, and their arcuate or lunar outline contributes to comfort and sanitation in wearing the denture. Full palate coverage is unnecessary because of the strong anchoring of denture 10 in the mouth.

Plate body portion 12 has fixed thereon and exposed externally thereof tooth replacement components in register, inward to outward-wise, with the plate indent and

other formations

13, 14 and 15. There are four such incisor components, of which three, as designated 21, are located along the front of the dentures arch in correspondence with the three incisor indentations 13 of plate portion 12, the fourth component 21 being at the extraction zone 14; and two canine or cuspid tooth replacement components 22 registered respectively with the plate indentations 15.

The sectional views of FIGS. 6, 7 and 8 illustrate typically how the tooth structures of worn or partial height tooth substances, such as the

incisors

21, 21 and canines 22, are in effect re-constituted. Thus, FIG. 6, an enlarged section through FIG. 5 in the jaw zone at which an extraction has been performed, shows the vacant gum space 14 of the denture (see also FIG. 3) as being backed from beneath, and directly beneath the gum portion 4 at which masticating force is applied by a molded rear tooth portion 24 of substantial mass, which affords a grinding surface at 26 for mated occlusion with a corresponding lower jaw incisor tooth. Tooth 21', as thus in part constituted by portion 24, is forwardly and laterally flanked by a relatively thin shell 25 faithfully simulating the appearance of a natural corresponding incisor. This shell mates about the backingportion 24 and the space between the two is filled with a hard, dense and tough synthetic resin mass 27 which, in combination with rear backup member 24, affords a solid tooth pillar through which the force of mastication is transmitted between the upper jaw and the lower jaw. An appropriate resin or other plastically moldable and hard-setting material constitutes the two

masses

24 and 27.

As for the shell 25, it is preferably formed of an appropriate white acrylic resin, or it may be in a form produced by grinding and polishing a commercially available artificial porcelain tooth to an appropriate shell outline and appearance. As appears in FIG. 6, it is located a bit forwardly of the gum portion 4.

FIG. 7 is a section through an incisor tooth zone in which the three much worn, but periodontally sound, tooth stubs 3 remain, mating into internal depressions 13 of plate portion proper 12. The internal and external make-up of this incisor replacement 21, including front shell or cap 25, basic back-up and grinding portion 24 and fill-in mass 27 are the same as described in connection with FIG. 6, although differing somewhat in form and proportion, of course. It is seen that the

masses

24 and 27 constitute a strong force-transmitting pillar or column beneath and in precise vertical register with the stub 3, hence directly backed rigidly by the jaw. Actually a main masticative grinding effort takes place at the back-up surface and it is an extremely great force. The forward shell 25 bears little or no stress in the bite.

FIG. 8 represents a section similar to FIG. 7 at the less seriously worn incisor stub 3 and, again, parts and relationships are as described in reference to FIGS. 6 and 7, hence corresponding numerals are employed in all three instances.

The section of FIG. 10 is through a zone in FIG. 9 at which the plate member 12 affords an opening 16 receiving the sound bicuspid or premolar 6, or possibly a tooth previously pre-capped. The effective mastication of this tooth is preserved and matched with that of the

re-constituted stub teeth

13 and 15.

For the rest, the denture 10 is equipped with purchased anterior and posterior

molar members

28, 29, replacing extractions, and these are set in place on plate member 12 in the manner described in relation to FIG. 6, i.e., at a zone at which an extraction had also been performed. In general, a degree of skill will be required of the dentist and technician in insuring that the arch-array of replacement and natural teeth, in particular across the exposed shell or cap portions 25 as they merge with one another and teeth to the rear, will present a natural appearance. Such degree of skill is only to be expectedof competent practitioners.

As appears from the above, the nature of the cause of damage to the tooth stub, whether by wear, breakage or the like, is of no significance to the invention, hence the term first applied hereabove is to be construed broadly. Similarly, it is to be understood that the damage may exist at any one location or a number of locations on either the upper or lower jaw, or both. The mode and means of compensation are essentially the same in any instance.

What is claimed is:

1. A denture for use with a jaw which presents at least one damaged tooth stub projecting from the gum substantially less than before damage, said denture comprising a basic gum portion having surfaces for engaging and fitting substantially over inwardly and outwardly facing surfaces of said gum, said gum portion including a surface between and integral with said firstnamed surfaces thereof for vertically engaging the jaw arch, said integral surface having at least one internal depression therein which is adapted to be engaged by and specially fitted with a damaged portion of a said damaged tooth stub, thus to provide through said integral surface and stub a positive and direct bitesupporting back-up of the denture on a portion of said jaw, said gum portion of the denture having artificial tooth means thereon in a number corresponding at least to the number of tooth stubs, said means being in substantial register with a said depression of said gum portion.

2. A full denture for use with a jaw which presents at least one damaged tooth stub projecting from the gum substantially less than before damage, said denture comprising a basic gum portion having surfaces for engaging and fitting substantially over the pairs of buccal and lingual-facing surfaces of said gum, as well as any corresponding frontal surfaces in the plane of the arch of the jaw, said gum portion including a surface between and integral with said first-named surfaces thereof for vertically engaging the jaw arch, said integral surface having at least one internal depression therein which is adapted to be engaged by and specially fitted with a damaged portion of a said damaged tooth stub, thus to provide through said integral surface and stub a positive and direct bite-supporting back-up of the denture on a portion of said jaw, as well as to positively locate and confine the denture laterally in relation to the jaw and gum, said gum portion of the denture having artificial tooth means thereon in a number corresponding at least to the number of tooth stubs, said means being in substantial register with a said depression of said gun portion.

3. The denture of claim 1, in which said gum portion also has a surface for engaging and fitting directly on an area of the gum at which a tooth extraction has occurred.

4. The denture of claim 1, in which said gum portion also has an opening for fitting and receiving a relatively undamaged tooth of the jaw.

5. The denture of claim 1, in which said gum portion also has a surface for engaging and fitting directly on an area of the gum at which a tooth extraction has occurred, and an opening for fitting and receiving a relatively undamaged tooth of the jaw.

6. The denture of claim 2, in which said gum portion also has a surface for engaging and fitting directly on an area of the gum at which a tooth extraction has occurred, and an opening for fitting and receiving a relatively undamaged tooth of the jaw.

7. The denture of claim 1, in which said tooth means comprises at least one replacement tooth member fixed on said basic gum portion and including a back-up portion in vertical register with a said depression of the gum portion, and a shell portion in inward-to-outward register with said back-up portion, major mastication force in the Zone of register being transmitted by the stub through said back-up portion.

8. The denture of claim 2, in which said tooth means comprises at least one replacement tooth member fixed on said basic gum portion and including a back-up portion in vertical register with a said stub-engaged depression of the gum portion, and a shell portion in inwardto-outward register with said back-up portion, major mastication force in the zone of register being transmittedby the stub through said back-up portion.

' 9; The denture of claim 3, in which said tooth means comprises at least one replacement tooth member fixed on said basic gum portion and including a back-up portion in vertical register with a said depression of the gum portion, and a shell portion in inward-to-outward register with said back-up portion, major mastication force in the zone of register being transmitted by the stub through said back-up portion.

10. The denture of claim 4, in which said tooth means comprises at least one replacement tooth member fixed on said basic gum portion and including a back-up portion in vertical register with a said depression of the gum portion, and a shell portion in inward-to-outward register with said back-up portion, major mastication force in the zone of register being transmitted by the stub through said back-up portion.

1 l. The denture of claim 5, in which said tooth means comprises at least one replacement tooth member fixed on said basic gum portion and including a back-up portion in vertical register with a said depression of the gum portion, and a shell portion in inward-to-outward register with said back-up portion, major mastication force in the zone of register being transmitted by the stub through said back-up portion. t 9 l 9

Claims

1. A denture for use with a jaw which presents at least one damaged tooth stub projecting from the gum substantially less than before damage, said denture comprising a basic gum portion having surfaces for engaging and fitting substantially over inwardly and outwardly facing surfaces of said gum, said gum portion including a surface between and integral with said firstnamed surfaces thereof for vertically engaging the jaw arch, said integral surface having at least one internal depression therein which is adapted to be engaged by and specially fitted with a damaged portion of a said damaged tooth stub, thus to provide through said integral surface and stub a positive and direct bite-supporting back-up of the denture on a portion of said jaw, said gum portion of the denture having artificial tooth means thereon in a number corresponding at least to the number of tooth stubs, said means being in substantial register with a said depression of said gum portion.

8. The denture of claim 2, in which said tooth means comprises at least one replacement tooth member fixed on said basic gum portion and including a back-up portion in vertical register with a said stub-engaged depression of the gum portion, and a shell portion in inward-to-outward register with said back-up portion, major mastication force in the zone of register being transmitted by the stub through said back-up portion.

9. The denture of claim 3, in which said tooth means comprises at least one replacement tooth member fixed on said basic gum portion and including a back-up portion in vertical register with a said depression of the gum portion, and a shell portion in inward-to-outward register with said back-up portion, major mastication force in the zone of register being transmitted by the stub through said back-up portion.

11. The denture of claim 5, in which said tooth means comprises at least one replacement tooth member fixed on said basic gum portion and including a back-up portion in vertical register with a said depression of the gum portion, and a shell portion in inward-to-outward register with said back-up portion, major mastication force in the zone of register being transmitted by the stub through said back-up portion.