Endosseous implant for prosthetic teeth

Abstract

An endosseous implant for prosthetic teeth comprising at least two spaced apart pairs of spaced apart relatively thin, flat vertically straight legs, each leg having a constant thickness and width from top to substantially the bottom, and preferably, a vertically tapered tip on the bottom of each leg, an upwardly arcuate, relatively thin, flat upper bridge joining the tops of the outermost legs of each said pair, an upwardly arcuate relatively thin, flat lower bridge vertically spaced apart from the upper bridge joining the tops of the innermost legs of each said pair, the bridges having a constant thickness preferably equal to the thickness of the legs, a relatively thin, flat arm joining the inner and outer leg of each said pair in proximity to their tops and preferably extending between the juncture of the legs with the respective bridges to which they are joined, the arms having a constant thickness preferably equal to the thickness of the legs, and a post formed on the uppermost bridge extending vertically upwardly therefrom, the top of the post preferably having at least one pair of intersecting grooves, the legs, bridges and arms collectively preferably having a plurality of transverse openings.

Description

BACKGROUND OF INVENTION

Endosseous implants are gaining wide acceptance in the dental arts as means for supporting prosthetic teeth and bridges. The fundamental purpose of the implant is to relieve the gum of the burden of supporting the denture, transmitting the force applied to the dentures directly to the mandible bone. Thus, changes in the soft tissue of the gum will not result in loosening or decreased support of the dentures. Moreover, since the burden of the denture is removed from the gum, trauma and degeneration of gum tissue is avoided from this source.

Many endosseous implant blade configurations have been proposed. However, known blades suffer from one common deficiency, they are all relatively easily dislodged or loosened from the mandible after a relatively short period of use.

In some instances, implant blades have been proposed which are asymmetrical and, as a result, transmit forces to the mandible in an uneven pattern, resulting in either fracture of the implant blade or loss of anchoring by the mandible or maxillary.

Other implant blade configurations have been proposed employing a plurality of depending legs which are other than vertically straight. In some configurations the blade is arcuate from top to bottom. In other configurations the blade is flared at the bottom being wider at the bottom than at the top. In other configurations, the blade is tapered in thickness from the top to the bottom. As a result of these configuration characteristics, the blade become loose, frequently rotates, and sometimes fractures. The tooth becomes malpositioned and loses its support. In addition, as a result of such movement the mandible and gum are traumatized.

Still other implant blades have been proposed with generally horizontal members connecting the bottoms of vertical members. Such blades generate excessive trauma to the mandible during implanation with poor fibro-collagenous and osteogenesis.

The bearing load of the blade is enormous and must be supported by a relatively thin member to which the post supporting the prosthetic tooth is attached. In almost all known implant blades, the generally horizontal bridging member upon which the mounting post is formed is either horizontally straight or arcuate downwardly. Thus, the forces transmitted by the post tend to spread the depending members apart to an excessive degree again generating undesirable rotational forces on the blade.

It is among the objects and advantages of the present invention to provide an endosseous implant for prosthetic teeth which is substantially undistortable under stress generated on and transmitted by the tooth mounting post.

Another object of the present invention is to provide an endosseous implant as aforesaid which takes maximum advantage of potential fibro-mucosis by providing relatively small transverse passages in and between the members of the blade through which medulla tooth tissue generates thereby anchoring the blade against any movement, longitudinal, latitudinal or rotational.

Still another object of the present invention is to provide an endosseous implant aforesaid in which the legs may be easily shortened to accommodate for variations in mandible thicknesses.

Still another object of the present invention is to provide an endosseous implant as aforesaid which generates a minimum of trauma to the tooth during implantation but which spans a large distance longitudinal to the mandible to provide maximum anchoring.

SUMMARY OF INVENTION

An endosseous implant for prosthetic teeth comprising at least two spaced apart pairs of spaced apart relatively thin, vertically straight legs, each leg having a constant thickness and width from the top to substantially the bottom, an upwardly arcuate, relatively thin, flat upper bridge joining the tops of the outermost legs of each said pair, an upwardly arcuate relatively thin, flat lower bridge vertically spaced apart from the upper bridge joining the tops of the innermost legs of each said pair, a relatively thin, flat arm joining the innermost and outermost leg of each said pair in proximity to their tops, and a post formed on the uppermost bridge extending vertically upwardly therefrom.

PREFERRED EMBODIMENT OF INVENTION

These objects and advantages as well as other objects and advantages may be achieved by the endosseous implant for prosthetic teeth claimed herein two preferred embodiments of which are illustrated in the drawings in which:

FIG. 1 is a side elevational view of an endosseous implant employing a single prosthetic tooth mounting post;

FIG. 2 is an end elevational view of the endosseous implant illustrated in FIG. 1;

FIG. 3 is a top plan view of the endosseous implant illustrated in FIGS. 1 and 2;

FIG. 4 is a side elevational view of an alternate form of endosseous implant employing two prosthetic tooth supporting posts;

FIG. 5 is an end elevational view of the endosseous implant illustrated in FIG. 4;

FIG. 6 is a top plan view of the endosseous implant illustrated in FIGS. 4 and 5.

Referring now to the drawings in detail and in particular to FIGS. 1, 2 and 3, the endosseous implant comprises spaced apart pairs of spaced apart vertically depending legs 11, 12, 13 and 14. The legs 11, 12, 13 and 14 are vertically straight and parallel having an equal width and equal thickness from top to substantially the bottom thereof. Each of the legs 11, 12, 13 and 14 are preferably provided with vertically tapering tips respectively 15, 16, 17 and 18. Preferably the space 19 between legs 11 and 12 and the space 20 between legs 13 and 14 are equal in width and substantially less than the space 21 between legs 12 and 13.

The outermost depending legs 11 and 14 are joined together at their tops by a relatively thin, flat upwardly arcuate bridge 22. Preferably, the bridge 22 is formed integrally with legs 11 and 14 and is of constant thickness and preferably of constant width.

The innermost legs 12 and 13 of the respective pairs of legs are joined together at their tops by an upwardly arcuate lower bridge 23. The lower bridge 23 is of constant thickness throughout, preferably equal to the thickness of the legs 12 and 13 and preferably also equal to the thickness of legs 11 and 14 and upper bridge 22.

Relatively thin, flat arms respectively 24 and 25 join the innermost and outermost legs of each said pair of legs respectively 11-12 and 13-14. Preferably, arms 24 and 25 extend between and form integrally with the juncture of the legs which they join with the respective bridges to which they are joined. The arms 24 and 25 are of constant thickness, preferably equal to the thickness of the legs 11, 12, 13 and 14 and the bridges 22 and 23.

The top edge 26 of the upper bridge 22 is flared outwardly on its opposite sides to define wedge shaped flanges 27 and 28 the purpose for which will be detailed later.

A prosthetic tooth mounting post 29 is joined to the top edge 26 of bridge 22 at its center by a tapered neck 30. The top 31 of the post 29 is provided with a pair of intersecting grooves 32 and 33 which preferably extend transversely across the top 31 of the post 29.

The length of the legs 11, 12, 13 and 14 are relatively great with respect to the combined widths of bridges 22 and 23 and the space 34 therebetween. The legs 11, 12, 13 and 14, the bridges 22 and 23 and arms 24 and 25 are collectively provided with a plurality of transverse countersunk holes 35,35 etc.

The points of intersection of all of the respective components of the implant blade, the legs, arms and bridges are provided with a radius to avoid angular intersections. In addition, the holes 35 are provided with a countersunk rim 36.

An alternate form of endosseous implant blade is illustrated in FIGS. 4, 5 and 6. Such a blade employs a pair of prosthetic tooth mounting posts and is useful for supporting a plurality of teeth joined together in a bridge. The implant blade illustrated in FIGS. 4, 5 and 6 is similar in all respects to the implant blade illustrated in FIGS. 1, 2 and 3. There are provided spaced apart pairs of spaced apart relatively thin, flat, vertically straight legs 37, 38, 39 and 40. The legs 37, 38, 39 and 40 are of constant thickness from the top to substantially the bottom thereof, the bottoms each being provided with a vertically tapered tip respectively 41, 42, 43 and 44.

The outermost legs 37 and 40 of the respective pairs of legs 37-38 and 39-40 are joined together at their tops of an upwardly arcuate upper bridge 45. The upper bridge 45 is preferably formed integrally with the legs 37 and 40, is of constant thickness, preferably equal to the thickness of legs 37 and 40.

The innermost legs 38 and 39 of the said pairs 37-38 and 39-40 are joined together at their tops by an upwardly arcuate lower bridge 46 spaced away from the upper bridge 45. The lower bridge 46 is of constant thickness, preferably equal to the thickness of legs 38 and 39.

A pair of arms 47 and 48 join the respective pairs of legs 37-38 and 39-40 together at their tops. Preferably, the arms 47 and 48 are formed integrally with the legs 37-38 and 39-40 extending between the juncture of the respective legs and bridges. An intermediate arm 49 joins the upper bridge 45 and lower bridge 46 at their respective centers.

The space 50 between legs 37 and 38 and the space 51 between legs 39 and 40 are preferably equal and substantially smaller than the space 52 between legs 42 and 43. The length of the legs 37 and 40 are substantially greater than the combined widths of the bridges 45 and 46 and the space therebetween 53.

The upper bridge 45 is provided with a pair of prosthetic tooth mounting posts 54-54 each joined to the bridge 45 by a tapered neck 55-55. The top 56 of each of the posts 54 is provided with a pair of intersecting grooves 57-58 extending transversely across the respective tops 56.

Each of the legs 37, 38, 39 and 40, the upper and lower bridges 45 and 46 and the arms 47 and 48 are collectively provided with a plurality of transverse holes 59,59, etc., which are provided with a countersunk rim 60 on each of the faces of the said members.

The intersection of each of the component members of the implant blade is provided with a radius to provide against angular or sharp intersections.

The top edge 61 of the upper bridge 45 is outwardly flared to define wedge shaped flanges 62-63 having the same function as flanges 27 and 28 in FIGS. 1, 2 and 3.

In operation, the implant blade is positioned above the gum above that portion of the mandible to bear the stress or support of the prosthetic tooth or bridge. Preferably, the gum is layed back to expose the mandible. With young persons, the mandible is substantially cartilaginous. In such persons, the implant blade may be forced downwardly into the mandible either by light tapping or by constant downward pressure. The tapered tips on the legs of the implant blade facilitate penetration of the mandible. In older persons or in persons whom the natural teeth have been removed for some time the uppermost portion of the mandible becomes calcified. In such persons, the calcified portion must be cut by means of an appropriate dental instrument to provide an entrance for the implant blade. The flared upper edge 26 of upper bridge 22 in FIGS. 1, 2 and 3 and the flared upper edge 61 of upper bridge 45 in FIGS. 3, 4 and 5 provide a seal for the cut in the mandible bone, the respective wedge shaped protrusions 27-28 and 62-63 intruding into the cut which is normally somewhat irregularly shaped.

During implantation the legs of the implant blade penetrate the cartilaginous medullary portion of the mandible bone stimulating fibro-mucosis. Similarly, penetration of the lower bridge 23 and 46 also stimulates fibro-mucosis. This results in bone material regenerating through the respective opening 35 in FIGS. 1, 2 and 3 and 59 in FIGS. 4, 5 and 6 as well as in the space 34 or 35 intermediate the upper and lower bridges 22-23 and 45-46. The regenerated tissue intruding through these openings firmly anchors the implant blade against any movement longitudinal, latitudinal or rotational. Nevertheless, the total amount of the mandible traumatized by penetration of the legs and bridges is relatively small as compared to the overall longitudinal extension of the blade.

In the event that the mandible bone is of varying thickness, or is exceptionally narrow, the legs may be easily cut through the openings to adjust their length. Nevertheless, the strength of the entire blade remains unaltered notwithstanding the shortening of the legs, all forces and stresses upon the mounting post being transmitted vertically downwardly into the mandible without distortion of the blade.

Of particular note is the fact that the upper and lower bridges 22-23 and 45-46 are upwardly arcuate. This configuration transmits vertical forces from the posts 29 or 54 vertically downwardly into the legs without causing deflection of the legs outwardly or inwardly which would result in loosening of the blade from the mandible.

Of equal note is the fact that the legs are of constant thickness from the top to substantially the bottom thereof. In known configurations, many of the legs are vertically tapered to facilitate penetration. However, the vertical taper also contributes to vertical loosening of the implant blade. Preferably, all of the components of the blade should be of equal thickness with only the tips of the legs being vertically tapered. In this fashion, the implant blade makes the same width penetration throughout the mandible with no portions being thicker than anothers.

The intersecting grooves 32-33 in post 29 and 57-58 in posts 54,54 provide a seat for complementary ribs on the bottom of prosthetic teeth mounted thereon. Such complementary grooves and ribs provide an anchor against rotation of the prosthetic tooth and assist in orientation thereof since the tooth must be placed on the post after implantation of the blade.

In the embodiment of the invention illustrated in FIGS. 4, 5 and 6, the arm 49 intermediate the upper bridge 45 and lower bridge 46 provides additional vertical support against downward deflection of the respective bridges which in turn would result in outward deflection of the legs. The intermediate arm 49 is unnecessary in the smaller single post configuration illustrated in FIGS. 1, 2 and 3 since the forces transmitted by the post are necessarily symmetrical. The forces transmitted by posts 54,54 in FIGS. 4, 5 and 6 might well not be symmetrical but the configuration of the implant blade distributes the forces in as wide and equal a fashion as possible without distortion of the blade. In addition, the arm 49 provides supplemental support between bridges 45 and 46 which are longer than bridges 22 and 23 in FIGS. 1, 2 and 3.

Of particular note is the fact that all intersecting surfaces and members of the blades illustrated in all of the drawings are provided with a radius. Angular or sharp intersections provide a site for the accumulation of fungus and are decidedly undesirable. This is also the reason for the countersunk rim 36 around the openings 35 in FIGS. 1, 2 and 3 and 60 in FIGS. 4, 5 and 6. Preferably, the entire implant blade is fabricated integrally from a thin flat sheet of material so as to maintain constant thickness throughout all members with the exception, of course, of the mounting post. It has been found that the preferred material of fabrication is exceptionally pure titanium to which the body tissue appears to exhibit minimal rejection characteristics.

The foregoing description is merely intended to illustrate an embodiment of the invention. Component parts have been shown and described. They each may have substitutes which may perform a substantially similar function; such substitutes may be known as proper substitutes for the said components and may have actually been known or invented before the present invention.

Claims

I claim:

1. An endosseous implant for prosthetic teeth, comprising,

a. at least two spaced apart pairs of spaced apart relatively thin, vertically straight legs, each leg having a constant thickness and width from the top to substantially the bottom, the distance between the said pairs of legs being greater than the distance between the respective legs of each pair,

b. an upwardly arcuate, relatively thin, flat upper bridge joining the tops of the outermost legs of each said pair,

c. an upwardly arcuate relatively thin, flat lower bridge vertically spaced apart from the upper bridge joining the tops of the innermost legs of each said pair,

d. a relatively thin, flat arm joining the innermost and outermost leg of each said pair in proximity to their tops, and

e. a post formed on the uppermost bridge extending vertically upwardly therefrom.

2. An endosseous implant for prosthetic teeth comprising,

a. the structure in accordance with claim 1 in which

b. the said legs, bridges and arms are collectively provided with a plurality of transverse openings.

3. An endosseous implant for prosthetic teeth comprising,

a. the structure in accordance with claim 1 in which,

b. each arm and each bridge has a constant thickness.

4. An endosseous implant for prosthetic teeth comprising:

a. the structure in accordance with claim 1 in which

b. each leg has a constant width from the top to substantially the bottom.

5. An endosseous implant for prosthetic teeth comprising

a. the structure in accordance with claim 2 in which

b. each leg has a constant width from the top to substantially the bottom.

6. An endosseous implant for prosthetic teeth comprising,

a. the structure in accordance with claim 5 in which

b. each arm and each bridge has a constant thickness.

7. An endosseous implant for prosthetic teeth comprising,

a. the structure in accordance with claim 6 in which

b. the legs, arm and bridges have substantially the same constant thickness.

8. An endosseous implant for prosthetic teeth comprising,

a. the structure in accordance with claim 2 in which

b. the legs of each pair are spaced apart a distance substantially less than distance between the said pairs.

9. An endosseous implant for prosthetic teeth comprising,

a. the structure in accordance with claim 2 in which,

b. the top of the post is provided with a pair of intersecting grooves.

10. An endosseous implant for prosthetic teeth comprising,

a. the structure in accordance with claim 2 in which

a. a plurality of posts formed on the uppermost bridge extending vertically upwardly therefrom, the posts being positioned symmetrically with respect to a vertical axis through the center of the said bridges,

c. at least one supporting arm joining the uppermost and lowermost bridges, the supporting arm being symmetrical with respect to a vertical axis through the center of the said bridges.