Title:
Dental implant
Kind Code:
A1


Abstract:
The invention provides dental implants for fixed and removable prosthetic devices, and has application to single tooth replacement, e.g., caps and crowns, and multiple tooth replacement using one or more implants, e.g., bridges, and multiple implants for full and partial prosthetic devices. Dental implants according to embodiments of the invention comprise a post or posts inserted into the jawbone and a stabilizer that is loaded, in the general area of the gum line, against the jawbone using the post or posts. The stabilizer is secured to each post, loaded against the jawbone, by a fastener system, e.g., a nut threaded to each post.



Inventors:
Adams, Curtis (Flemington, NJ, US)
Application Number:
11/603749
Publication Date:
05/22/2008
Filing Date:
11/22/2006
Primary Class:
Other Classes:
433/173
International Classes:
A61C8/00
View Patent Images:
Related US Applications:



Primary Examiner:
EIDE, HEIDI MARIE
Attorney, Agent or Firm:
FROMMER LAWRENCE & HAUG (745 FIFTH AVENUE- 10TH FL., NEW YORK, NY, 10151, US)
Claims:
1. A dental implant adapted to be installed in a mouth on a permanent basis, comprising: at least one post which includes a screw thread extending along at least a portion thereof, each post being adapted to be secured in a mouth to a jawbone using the screw thread with an end thereof generally facing an opposing jawbone, each post having a diameter within the range of 1.6 mm to 3.7 mm; a stabilizer including a hole therein for each post of the dental implant, the stabilizer being adapted to support a prosthetic device replacing at least one tooth at a in the mouth in which the implant is to be installed, and to contact the jawbone at that location along a portion of the jawbone that faces the opposed jawbone: a fastener system which in cooperation with the at least one post is adapted to engage the stabilizer and load the stabilizer against the jawbone in contact therewith along the portion thereof that faces the opposed jawbone

2. A dental implant adapted to be installed in a mouth on a permanent basis, comprising: at least two posts each of which includes a screw thread extending along at least a portion thereof, each of the posts being adapted to be secured in a location in the mouth to a jawbone using the screw thread with an end thereof generally facing an opposing jawbone, each post having a diameter within the range of 1.6 mm to 3.7 mm; a stabilizer including a hole therein for each post of the dental implant, the stabilizer being adapted to support a prosthetic device replacing at least one tooth at a location in the mouth in which the is to be installed, and to contact the jawbone at that location along a portion of the jawbone that faces the opposed jawbpone; a fastener system which in cooperation with the at least two posts is adapted to engage the stabilizer and load the stabilizer against the jawbone in contact therewith along the portion thereof that faces the opposed jawbones

3. A dental implant installed in a mouth on a permanent basis, comprising: at least one post which includes a screw thread extending along at least a portion thereof, each post being secured to a jawbone at least using the screw thread thereof with an end thereof general1y facing an opposing jawbone, each post having a diameter within the range of 1.6 mm to 3.7 mm; a stabilizer including a hole therein for each post of the dental implant, the stabilizer being adapted to support a prothetic device replacing at least one tooth at a location in the mouth in which the implant is to be installed, the stabilizer contacting the jawbone at that location along a portion of the jawbone that faces the opposed jawbone with a respective post in alignment with a respective stabilizer hole; and a fastener system which in cooperation with at least one post engages the stabilizer and loads the stabilizer against the jawbone in contact therewith along the portion thereof that faces the opposed jawbone.

4. The dental implant of claim 1, 2 or 3, wherein the stabilizer comprises a platform including opposed major sides and at least one minor side.

5. The dental implant of claim 4, wherein: the opposed major sides of the platform are parallel and the at least one minor side is transverse to the major sides.

6. The dental implant of claim 1 or 2, wherein each post is adapted to extend beyond the stabilizer through a respective hole therein and the fastener system comprises a threaded nut for each post and a complementarily threaded portion of a respective post in the portion thereof adapted to extend beyond the stabilizer.

7. The dental implant of claim 1 or 2, comprising at least one anchor adapted to be attached to the dental implant projecting from the stabilizer and adapted to assist in securing the prosthetic device to the dental implant.

8. The dental implant of claim 1, wherein the dental implant is adapted to be installed at a location in the mouth formerly occupied by a tooth having a single root, and wherein the dental implant comprises a single post.

9. The dental implant of claim 3, wherein the dental implant is installed at a location in the mouth formerly occupied by a tooth having a single root, and wherein the dental implant comprises a single post.

10. The dental implant of claim 1 or 2, wherein the dental implant is adapted to be installed at a location in the mouth formerly occupied by a tooth having two or more roots, and wherein the dental implant comprises at least two posts.

11. The dental implant of claim 3, wherein the dental implant is installed at a location in the mouth formerly occupied by a tooth having two or more roots, and wherein the dental implant comprises at least two posts.

12. A combination of a dental implant according to claim 1, 2 or 3 and a prosthetic device adapted to be attached to the implant.

13. The combination of claim 12, wherein the prosthetic device comprises structure replacing a single tooth.

14. The combination of claim 12, wherein the prosthetic device comprises structure forming part of a multi-tooth replacement.

15. The dental implant of claim 1, 2 or 3 wherein the dental implant is adapted to receive at least part of a fixed prosthetic device.

16. The dental implant of claim 1, 2 or 3 wherein the dental implant is adapted to receive at least part of a removable prosthetic device.

17. A method of installing a dental implant in a mouth on a permanent basis, the dental implant comprising at least one post having a diameter within the range of 1.6 mm to 3.7 mm, a stabilizer with a hole therein for each post adapted to support a prosthetic device replacing at least one tooth at a location in the mouth in which the implant is to be installed, and a fastener system for engaging the stabilizer loaded against and in contact with a jawbone at the location in the mouth in which the implant is to be installed along a portion of the jawbone that faces the opposed jawbone, the method comprising: securing each post to the jawbone with an end thereof generally facing an opposing jawbone; positioning the stabilizer with each ho1e thereof aligned with a respective post and in contact with the jawbone at the location in the mouth in which the implant is to be installed along the portion of the jawbone that faces the opposed jawbone; and operating the fastener system to engage the stabilizer and load the stabilizer against the jawbone in contact therewith along the portion of the jawbone that faces the opposed jawbone.

18. The method of claim 19, wherein each post as secured to the jawbone includes a portion extending beyond the stabilizer, and wherein the fastener system comprises a screw thread extending in the portion of each post extending beyond the stabilizer and a threaded nut, and wherein operating the fastener system comprises threading a respective nut to the threaded portion of a respective post extending beyond the stabilizer and torqueing the respective nut to load the stabilizer against the jawbone.

19. The method of claim 17, wherein the step of positioning the stabilizer follows the step of securing each post to the jawbone.

20. The dental implant of claim 3, wherein each post extends beyond the stabilizer through a respective hole in the stabilizer and the fastener system comprises a threaded nut for each post and a complementarily threaded portion of a respective post extending beyond the stabilizer.

21. The dental implant of claim 3, comprising at least one anchor attached to the dental implant projecting from the stabilizer and adapted to assist in securing the prosthetic device to the dental implant.

22. The dental implant of claim 1, 2 or 3, wherein the dental implant is adapted to receive at least part of a prosthetic device.

23. A dental implant adapted to be installed in a mouth on a permanent basis, comprising: at least one post which includes a screw thread extending along at least a portion of the at least one post, each post being adapted to be secured in a mouth to a jawbone using the screw thread with an end thereof generally facing an opposing jawbone, each post having a diameter within the range of 1 mm to 4 mm; a stabilizer including a hole therein for each post of the dental implant, the stabilizer being adapted to support a prosthetic device replacing at least one tooth at a location in the mouth in which the implant is to be installed, and to contact the jawbone at that location along a portion of the jawbone that faces the opposed jawbone; a fastener system which in cooperation with the at least one post is adapted to engage the stabilizer and load the stabilizer against the jawbone in contact therewith along the portion thereof that faces the opposed jawbone.

Description:

BACKGROUND OF THE INVENTION

The invention disclosed herein relates generally to dental implants for fixed and removable prosthetic devices and to fixed and removable prosthetic devices including such implants.

Implant dentistry dates back at least to the 1970s. See, e.g., Principles and Practice of Implant Dentistry, by Charles M. Weiss and Adam Weiss, Mosby Inc., 2001.

SUMMARY OF THE INVENTION

The invention provides dental implants for fixed and removable prosthetic devices and to fixed and removable prosthetic devices including such implants, and has application to, but is not limited to, one or more of the following: single tooth replacement, e.g., caps and crowns; multiple tooth replacement using one or more implants, e.g., bridges; and multiple implants for full and partial prosthetic devices. Embodiments of dental implants incorporating the invention may be installed in single or multiple root teeth locations.

Dental implants according to embodiments of the invention comprise a post or posts inserted into the jawbone extending therefrom towards the opposing jawbone, and a stabilizer that is loaded, in the general area of the gum line, against the jawbone, directly or indirectly through gum tissue, using the post or posts. The term loaded or loadable against the jawbone is meant in a broad sense and encompasses loading of the stabilizer against the jawbone in direct contact therewith or through gum tissue. According to some embodiments, the stabilizer is loaded against the jawbone by a force or forces derived from anchoring of the post or posts in the jawbone. For example, the stabilizer may be urged in compression against the jawbone via a tensile force applied to the post or posts. Implants according to the embodiments of the invention incorporating such stabilizers provide sufficient supporting surface area for a prosthetic device even where the size of the post(s) is relatively small, e.g., typically smaller than that of a post previously used for an implant at a particular implant location.

According to some embodiments, the stabilizer is configured to fit snugly into the implant location at the gum line, so as to be loadable against the jawbone. For example, the stabilizer is configured to fit in a space or cavity at the concerned implant location in the mouth, created by the absence of a tooth, or otherwise, loaded against the jawbone at the gum line. The term implant location is meant in a broad sense and corresponds at least generally to the location of a tooth formerly in the mouth. For example, the implant may be centered more or less in the location formerly occupied by a tooth, although the implant location may be offset from the center of the location of a tooth formerly in the mouth, e.g., where the space or cavity formerly occupied by the tooth is large or the implant is to be inserted where two or more adjacent teeth were formerly in the mouth.

Various configurations of stabilizers may be used, and the particular configuration corresponds generally to a cross-sectional slice of the tooth formerly at the implant location, e.g., such that the stabilizer occupies a substantial surface area, e.g., all or most of the surface area, occupied by the tooth at the gum line at the implant location. The surface area of the stabilizer is approximately that of the space or cavity at the gum line, i.e., the surface area of the tooth formerly at the implant location at the gum line. The thickness of the stabilizer is sufficient to withstand the compressive force(s) loading the stabilizer against the jawbone and to stabilize a prosthetic device attached to the implant. Also, according to some embodiments of the invention, the prosthesis extends over the stabilizer, which should have sufficient thickness to permit this.

In the illustrated embodiments, the stabilizer comprises a platform that includes opposed parallel major sides and at least one minor side transverse to the major sides, e.g., may have a generally solid rectangular configuration. The platform may be rectangular or trapezoidal in cross section, or may have other cross-sectional shapes.

According to some embodiments of the invention, the stabilizer is secured to the post, loaded against the jawbone, by a fastener system. In one embodiment, the platform includes a hole for each post, and a respective post is received in a respective hole and attached to the platform by the fastener system.

A dental implant according to some embodiments of the invention comprises at least one post which is inserted into a patient's jawbone extending towards the opposing jawbone and a stabilizer including a major side and a hole in the major side for each post of the dental implant. The relative sizes of each post and the stabilizer are such that a transverse dimension of the major side of a stabilizer is substantially larger than a largest transverse dimension, e.g., a diameter, of any of the posts at the location at which the particular post passes through a hole. Each hole and a portion of a corresponding post which in use would be received in a hole comprise complementary configurations. The configuration of a respective hole and the configuration of a respective post preferably provides but does not have to provide a snug fit, e.g., a tight or interference fit. The implant also includes a fastener system which, in use of the dental implant, secures the platform to at least one post loaded against the jawbone.

Any suitable post and any suitable insertion methodology may be used. For example, in the illustrated embodiments, each post includes a screw thread extending along at least the portion of the post which is to be threaded into the jawbone. In some embodiments, the threaded portion is circular in cross section, and the post diameter may be tapered. In these embodiments, each post is secured to the jawbone at least using the screw thread thereof with a free end of the respective post extending from the jawbone, and the stabilizer is positioned to receive a respective post in a respective hole with the major side of the stabilizer extending transverse to an axis of the post. In these embodiments. The free end of at least one post extends beyond the major side of the stabilizer and the at least one post and the stabilizer are secured by the fastener system and a portion or portions of the dental implant extend beyond the major surface of the platform as to be able to receive a prosthetic device.

In some embodiments, as mentioned above, the stabilizer comprises a platform including opposed parallel major sides and at least one minor side, where the at least one hole extends through the major sides. In the installed condition of the implant, the at least one post passes through the at least one hole with its free end extending beyond an adjacent major side of the platform.

In some embodiments, the implant includes at least one anchor which is attached to the implant projecting from the stabilizer or platform and adapted to assist in securing a prosthetic device to the dental implant.

Dental implants according to some embodiments of the invention may be installed at locations formerly occupied by teeth having one root or a plurality of roots. Generally, a post is inserted for each root at that location, and the platform has a hole for each post.

A method according to an embodiment of the invention for installing a dental implant of the type disclosed herein comprises providing a hole in a jawbone for each post of the implant positioned to be alignable with each hole in a stabilizer, installing the stabilizer with a free end of a respective post extending from a respective jawbone hole toward the opposing jawbone a distance sufficient to enter a respective hole in the stabilizer while the stabilizer contacts the jawbone or gum tissue adjacent thereto at the gum line. In an embodiment in which the stabilizer is to be installed in direct contact with the jawbone, the gum at the gum line is cut away to expose the jawbone and provide access thereto for the stabilizer to directly contact the jawbone. The stabilizer is mounted with each post received in a respective hole in the stabilizer and the stabilizer in contact with jawbone at the gum line (or gum tissue adjacent thereto), and the stabilizer is attached to the at least one post with the stabilizer loaded against the jawbone, e.g., by a fastener system.

According to some embodiments, the fastener system used to attach the stabilizer to the at least one post, includes a threaded nut for each post and a correspondingly threaded portion of the respective post.

BRIEF DESCRIPTION OF DRAWINGS

The invention is illustrated in the figures of the accompanying drawings, which are meant to be exemplary and not limiting, and in which like references are intended to refer to like or corresponding parts.

FIG. 1 is an exploded perspective view of a dental implant according to an embodiment of the invention.

FIG. 2 is an exploded perspective view of a dental implant according to another embodiment of the invention.

FIG. 3 is a diagram showing in perspective an inserted dental implant of the type depicted in FIG. 1 and an installed dental prosthetic device (a cap) according to an embodiment of the invention, and also teeth next to the implant.

FIG. 4 is a partial cross-sectional view from the side of the inserted dental implant and installed dental prosthetic device depicted in FIG. 3.

FIG. 5 is a diagram showing in perspective an inserted dental implant and an installed dental prosthetic device according to an embodiment of the invention, and also teeth next to the implant.

FIG. 6 is a partial cross-sectional view from the side of the inserted dental implant and installed dental prosthetic device depicted in FIG. 5.

FIG. 7 is a diagram similar to that of FIG. 5 showing in perspective two inserted dental implants and an installed dental prosthetic device (a bridge) according to another embodiment of the invention.

FIG. 8 is a diagram showing a front view of four inserted dental implants and an installed dental prosthetic device for the four lower incisor teeth locations and the two lower canine teeth locations according to an embodiment of the invention.

FIG. 9 is a diagram showing a front view of six inserted dental implants and an installed dental prosthetic device for the four lower incisor teeth locations and the two lower canine teeth locations according to an embodiment of the invention.

FIG. 10 is an exploded perspective view of a dental implant for a removable prosthetic device according to an embodiment of the invention.

The embodiment of the dental implant 10 depicted in FIG. 1 and the embodiment of the dental implant 10a depicted in FIG. 2 each comprise at least one post 12, and at least one stabilizer 14.

The stabilizer 14 may be is configured as described above and in some embodiments includes opposed major sides and at least one minor side. In the illustrated embodiments, the stabilizer comprises a platform 14, where the opposed major sides 15 are parallel and the at least one minor side 17 is transverse, e.g., generally normal, to the major sides. Other configurations and shapes may be used. For example, the major sides may be generally parallel or sloped relative to each other, or include multiple portions which intersect at a vertex or vertices, and the minor sides may not be parallel, but sloped relative to each other, or include multiple portions which intersect at a vertex or vertices. As a general matter, the stabilizer may be of generally solid rectangular or trapezoidal (e.g., see FIG. 4) configuration. The platform is generally plate-like or disc-like where the thickness is substantially less than the area of either major side. Depending upon the location of the implant, a stabilizer can have a perimeter or circumference of about 8 mm to about 25 mm. Also depending upon location, the stabilizer can have a thickness of about 2 mm to about 4 mm, with about 3 mm to 4 mm being preferred.

A fastener system referenced generally by 16 is associated with a post or posts 12. Each of the platforms 14 includes a through hole 18 for a respective post 12. The respective hole 18 and an intermediate portion 20 of each post 12 between the upper end 22 and the lower end 24 the respective post where the respective post passes through the respective hole in the inserted condition of the respective implant (see FIGS. 4 and 6) are complimentarily configured, where the size of the respective hole is slightly larger than the size of the respective post portion to provide a snug fit of the respective post in the respective hole. In some embodiments, the hole or holes 18 in the platform are not threaded. In such embodiments, the intermediate portion 20 of the post may or may not be threaded. Either or both the upper portion 26 and the lower portion 28 of the respective posts 12 are configured to allow the respective post to be passed through the respective hole during insertion of the particular implant. As discussed below, many post configurations other than those illustrated in FIGS. 1 and 2 may be used.

As discussed in more detail below, in the inserted condition of the implant 10, the platform 14 rests on or otherwise contacts and is loaded against the jawbone 34 at the gun line 36 (see FIGS. 4 and 6). When the platform is loaded against the jawbone through gum tissue, it is preferred that the gum tissue should not be soft tissue. Forcing the platform directly against the jawbone puts pressure on the bone, which maintains bone structure and avoids or reduces drift of the implant. This arrangement can prevent or reduce growth of soft tissue between the platform and the bone, which could otherwise lead to irritation or and/or bleeding, and can also promote gingival health.

In the illustrated embodiments, each of the posts 12 includes a thread 30 that extends at least along the lower portion 28 of the respective post, but may extend in other portions of the post (or additional threads may be provided) depending upon the fastener system 16 to be used and the configurations of the respective hole 18 and post intermediate portion 20. If the selected fastener system 16 includes threads on the upper portion 26 of the post, such threads may be separate from or related to (e.g., a continuation) of thread 30. In the embodiments depicted in FIGS. 1 and 2, the fastener system 16 comprises a nut 38 that is threaded to the upper portion 26 of the post. Although a pre-threaded system is preferred, in some embodiments, a self threading system may be used, e.g., either the post upper portion 26 or the nut 38 are not threaded and threads are created when the nut is “threaded” to the post upper portion. The fastener system 16 may include a counter-rotation feature to resist loosening, e.g., a lock washer 40, or a retention nut, or double nut (not shown).

For use with fixed prosthetic devices, a core 42 (see FIGS. 3 and 4) is built up surrounding the nut to accept the fixed dental prosthetic device, as described in more detail below, and can also hold the nut in place. Embodiments of the implant 10 may also include one or more anchors 48 used to assist in securing a fixed prosthetic device to the implant 10. Anchors 48 may be configured and attached to the implant 10 in any suitable manner. In the particular embodiment illustrated in FIGS. 1 and 2, an anchor 48 comprises one or more posts attached to or forming part of the platform 14. A post 48 may be attached to the platform 14 extending from the top surface thereof or at an edge, and may extend normal to the top surface of the of the platform or at an angle thereto. For example, a post extending from or adjacent an edge may be angled to extend inwardly relative to the platform, and a post extending close to an edge of the nut 38 may be angled to extend outwardly relative to the platform. As depicted in FIGS. 3 and 4, a post or posts 48 extend so that they can be embedded in the core 42 and possibly also in dental cement used to secure a prosthetic device to the implant.

The anchor may be attached to the platform in any suitable manner, e.g., by means of threads, suitable bonding technologies, e.g., adhesives or cements, ultrasonic, soldering, or welding, etc. For example, an end part may be inserted into a blind or through hole in the platform and attached as just described or by other suitable methods. A platform 14 may be formed with one or more posts 48 extending therefrom by any suitable technology, e.g., stamping, milling, casting or otherwise molding, etc.

In another embodiment, an anchor includes a base portion and a tab portion extending at an angle from the base portion. The base portion includes a hole therethrough and is mounted in the implant on the platform 14 with the upper portion of the post 12 passing through the hole, with the tab portion extending upwardly with at least a portion thereof exposed so it can be embedded at least in the core 42 and possibly also in a dental cement used to secure a prosthetic device to the implant. For example, for an anchor 48 having a base portion that extends beyond the outer periphery of the nut, the angle at which the tab extends from the base can be about 90°, but can be any suitable angle that provides for the tab to extend above the platform spaced from the nut and/or the post sufficiently to be embedded in the core and possibly in the dental cement used to secure a prosthesis to the implant. For example, for a base portion that extends just slightly beyond the outer periphery of the nut, the angle may be larger that 90° to provide clearance between the nut and the anchor tab.

Anchors may be made of any suitable material, e.g., the same material as the platform.

The sizes and configurations of the dental implants 10, 10a illustrated in FIGS. 1-7 may vary depending upon, e.g., the tooth position in which the particular implant is inserted. Generally, the upper portion 26 and intermediate portion 20 of the posts 12 are tubular and the diameter of the post decreases or tapers from the intermediate portion 20 to the lower end 24 of the post, e.g., the lower portion 28 is generally frustoconical. The entire post may be threaded or only portions thereof, as discussed above. For example, the upper portion of a post may be tubular and threaded (where the fastener system includes a threaded nut), the intermediate portion may be tubular or of rectangular or other cross sectional shape and need not be threaded, and the lower portion may be tubular or generally conical or frustoconical and threaded. In some embodiments, the post 12 may include stepped portions, or may be splined or splintered, or include structure other than or in addition to a thread to secure the post to the bone. For example, a post may be press-fitted to the jawbone rather than threaded. Many suitable post configurations other that those illustrated may be used and will be know to those working in this field.

The configuration, e.g., size (diameter and length) and shape of the particular post may vary as discussed above depending upon the tooth position at which the post will be implanted, characteristics of the particular patient, and other factors which may arise on an implant-by-implant and patient-by-patient basis. Generally, as discussed above, a post is implanted for each root of the tooth at the position in which the implant will be implanted, e.g., one post for the incisor and canine tooth positions and two or three posts for the molar tooth positions.

However, in the embodiment depicted in FIGS. 1-3, the entire post is threaded, with the upper and intermediate portions being tubular and the lower portion being generally frustoconical.

The posts 12 generally are made of a non-corrosive material or materials and have a high tensile strength. For example, a titanium post is suitable. The posts may be coated as known in the art, for better adhesion to bone. The posts have lengths of from about 18 mm to about 30 mm and outer diameters of from about 1 mm to about 4 mm. The diameter of most posts falls in the general range of from about 1.6 mm to about 3.7 mm, with about 2.2 mm being a likely mean. The particular length and diameter depends on a number of factors such as tooth position and patient conditions. The length of the post inserted into the jawbone can be about 10 mm to about 20 mm, and the length protruding from the jawbone can be about 8 mm to about 10 mm, part of which, e.g., about 3 mm to about 4 mm, passes through the platform and the remainder extending beyond the platform. The size of the nut (OD) can be about ¼ to about ½ the size of the platform (a cross dimension, e.g., diameter of the platform). The lower portions of the posts have thread sizes previously used for dental implant posts, and the upper portions have the same or similar threads. The nuts have threads that mate with those on the upper portion of the posts.

The platform is similarly made of a non-corrosive material or materials, e.g., stainless steel, a gold alloy, titanium. The size of the platform depends upon tooth position and/or patient characteristics, among possible other things. For example, a platform for a particular tooth location is shaped so as not to interfere with any adjacent teeth. Suitable platform sizes include: for incisor teeth positions, a surface area that can be in the general range of from about 4 mm to about 6 mm; and for molar teeth positions, a surface area (e.g., upper major surface) that can be in the general range of from about 16 mm to about 22 mm. The platforms generally are shaped as described above. As mentioned above, the thickness of the platform can be from about 2 mm to about 4 mm, and the perimeter or circumference from about 8 mm to about 25 mm.

FIGS. 3-7 illustrate examples of inserted dental implants with installed prosthetic devices. Methods of inserting the dental implants will be discussed below in connection with FIGS. 1-7.

For example, FIG. 3 illustrates a dental implant 10 of the type depicted in FIG. 1 implanted in the upper left, second incisor tooth position. For context, an outline of the second incisor tooth is illustrated in FIG. 3 by broken lines, and the canine and First molar teeth are also shown. The implant 10 depicted in FIGS. 1 and 3-4 is inserted as follows. A topical or local anesthetic is applied. (In most cases, the patient will not need full anesthesia, i.e., will not need to be put asleep.) The platform rests on and is loaded against the jawbone 34 at the gum line 36, as discussed above. In cases where direct contact is desired, the gum tissue (e.g., 3 mm-4 mm in thickness) is cut away at the gum line 36 where the platform would otherwise contact the gum. A gum line cut for the platform may be made before or after the post is inserted. One way to locate the portion of the gum to be cut away is to place the platform in the position in which it would be installed and punch the platform against the gum to create a cut in the gum. In cases where the platform is to be loaded against the jawbone through gum tissue, the presence of soft tissue at the gum line may indicate the need for a gum line cut or other procedure.

The location of the hole 56 (FIGS. 3-4) in the jawbone 34 for the post is determined depending upon, for example, tooth position and patient characteristics and generally corresponds to the root location at the particular tooth position. An MRI can assist in determining the location of the hole for the post. A pilot hole (not shown) (e.g., 3 mm deep) is drilled in the jawbone 34 in conventional fashion to accept the particular post 12 to be used. A template or guide stent (not shown) may be used to drill the pilot hole. The actual jawbone hole 56 is then drilled. In some embodiments of the invention, a self-threading system is used, i.e., the jawbone hole 56 is not threaded and a thread is created in the hole when the post 12 is tightened into the hole. Regardless of whether the hole 56 is self-threaded or not, its diameter is slightly less that the OD of the post (including threads). If the jawbone hole 56 is not self-threaded, then the hole is tapped to match the screw thread 30 of the post. The post 12 is threaded to the jawbone hole 56 in conventional fashion. As mentioned above, other types of posts may be used, and the insertion procedure depends at least to some extent on the particular post used.

Known wrench systems may be used to tighten a post to the jawbone. For example, a post may first be hand tightened into the jawbone hole, then wrench tightened with two or more wrenches ending with the use of a torque wrench. For example, a hand finger wrench may be used, followed by a wing nut wrench, followed by a 30 Newton torque wrench.

The platform 14 is then inserted onto the post 12. For example, the platform 14 is positioned over the post 12 with the post and the hole 18 in the platform 14 aligned and the platform raised (lowered for implantation in the lower jaw) until it abuts the jawbone 34 at the gum line 36. The platform 14 is positioned so that its upper major surface 15 is level with a line or plane at the concerned tooth position. The implant may include one or more anchors 48 extending above the platform 14.

The fastener system 16 then secures the platform 14 to the post with the platform loaded against the jawbone. As mentioned above, the fastener system 16 used for the implant embodiments depicted in FIGS. 1 and 2 comprises a nut 38 threaded onto the upper portion 26 of the particular post 12. After the lock washer 40 has been seated on the post 12, the nut 38 is initially loosely threaded to the post upper portion 26 until the platform is seated against the jawbone. The nut is torqued to a predetermined tension, e.g., 35 Newtons, using a conventional torque wrench to load the platform against the exposed jawbone. Different wrenches may be used to tighten the nut to the post before using the torque wrench to tighten the nut to the predetermined tension.

For the embodiments depicted in FIGS. 1, 2, 3 and 4, the core 42 is applied over the nut 38 and the anchors 48. As illustrated in FIG. 4, the core completely covers the nut and the anchors. However, part of the nut and/or the anchors and/or the top portion of the post may remain exposed to be embedded in a dental cement used to secure a prosthetic device to the implant. The core 42 may be built-up using glass polymer, silicon beads, resin, composite and/or metal, or any other suitable material or materials. This may be done manually or the core can be pre-formed and installed as a prefabricated core, which can include pre-drilled holes for the nut and the anchors. A prefabricated core is cemented to the nut and anchors. Use of a prefabricated core facilitates installation, particularly in the back of the mouth. The installed core is sized to leave space to be filled by a dental cement to attach a prosthetic device to the implant. In one embodiment, the core can be provided with a taper (as illustrated), e.g., 7°, to provide space between the core and the interior of the prosthetic device to apply cement. The outer surface of the core 42 may be grooved to promote adherence thereto of the cement.

The foregoing implantation procedures may be carried out during a single visit or multiple visits depending primarily upon site preparation requirements, e.g., whether a tooth extraction is involved. In most instances, the procedure can be performed in a single visit, even where a tooth is extracted during that visit. At the same that the implant is installed, or in a subsequent visit, preparation is made to mount a dental prosthetic device 66 to the implant. The prosthetic device 66 for implant 10 may be a cap 66a (FIGS. 3-4), or a crown 66b (FIGS. 5-6) for implant 10a replacing a single tooth, or a bridge 66c (FIG. 7) anchored to one dental implants 10a and either an existing tooth or another dental implant 10a and bridging one or more teeth positions, or fixed partial (or full) prosthetic device 66d-e (FIGS. 8-9) to be anchored to two or more implants 10 or 10a or at least one implant 10 or 10a and at least one existing tooth. The prosthetic devices 66 are otherwise conventional and may be made conventionally.

Preparation to mount a dental prosthetic device includes obtaining impressions in conventional fashion and providing them to the prosthesis manufacturer. The prosthetic device is typically custom made to fit the mouth and may involve milling for an exact fit. With respect to a cap 66a for the second incisor tooth position embodiment illustrated in FIGS. 3 and 4, the cap 66a is seated on the platform 14 extending over the minor sides 17 down past the gum line 36. Therefore, the impressions for the cap 66a are taken down to the gum line 36 past the platform sides 17 of the platform 14.

In some instances, an impression can be taken and the prosthetic device made prior to installation of the dental implant. In such cases, the dental implant and the appropriate prosthetic device can be installed in the same visit. In cases where the prosthetic device is to be installed in a visit subsequent to installation of the implant, a temporary prosthetic device (e.g., a conventional temporary cap, not shown, but in configuration similar to cap 66a) may be installed using a temporary cement. As for a permanent installation described below, the cement fills all of the interior of the cap and embeds the core 42 and any exposed portion of the anchors 48, the nut 38 and the upper post portion 26 to temporarily secure the temporary cap to the dental implant 10.

When the permanent cap 66a is ready, the temporary cap is removed if one has been installed, any needed preparation is performed, the cap 66a is tested for fit and any adjustments are made, etc., before final installation. The cap 66a is then installed using permanent cement which fills all of the interior of the cap 66a, and embeds the core 42 and any exposed portion of the anchors 48, the nut 38 and the upper post portion 26 to permanently secure the cap to the dental implant 10. Installation includes proper seating and positioning of the cap 66a over the platform 14 and against the jawbone 34, etc., as depicted in FIGS. 3 and 4.

The dental implant 10a illustrated in FIGS. 2 and 5-6 includes three posts 12 and is implanted in a molar tooth position. The description above for the single post implant 10 of FIGS. 1 and 3-4 generally applies to the multi-post implant 10a of FIGS. 2 and 5-6, including the discussions relating to posts, platforms and fasteners systems, except that post and platform sizes may differ and the platform 14 has a hole 18 for each post. Thus, the description above applies generally to posts 12, platform 14, nuts 38 and anchors 48 of the embodiment of FIGS. 2 and 5-6.

The insertion procedure for the multi-post implant 10a is also similar to that for the single post implant 10. After site preparation, generally as described above, a hole 56 is drilled in the jawbone 38 in conventional fashion to accept each of the particular posts 12 used. The positions of the holes 56 correspond generally to the root positions at the tooth location, and are selected based on site conditions.

After the posts have been inserted, the platform 14 is inserted onto the posts 12, e.g., by positioning the platform 14 over the posts 12 with the posts and the holes 18 in the platform 14 aligned and the platform lowered (raised for implantation in the upper jaw) until it abuts the jawbone 34 at the gum line 36. The platform 14 is positioned so that its upper major surface 15 is level with a line or plane at the concerned tooth position. The fastener system 16 is then tightened to secure the platform 14 to the posts loaded against the jawbone, i.e., the lock washers and nuts are applied as described above. The core 42 is applied as described above.

The implantation procedure for a multi-post implant, similar to a single post implant, may be carried out during a single visit or multiple visits depending primarily upon site preparation requirements, e.g., whether a tooth extraction is involved, and in most instances, can be performed in a single visit. The dental prosthetic device, a crown 66b in FIGS. 5-6, is installed as generally described above for the cap 66a.

The embodiment depicted in FIG. 7 includes two dental implants 10a of the type depicted in FIGS. 2 and 5-6 and a bridge prosthetic device 66c attached to the two implants 10a. Both implants 10a are implanted as described in connection with FIGS. 3-6. Impressions for the bridge 66c are taken generally as described above, including down to the gum line surrounding each platform and the bridged area. A temporary bridge or two temporary caps may be installed before the permanent bridge 66c. Proper positioning places the top of the bridge 66c in the patient's normal bite line for the concerned area.

In other embodiments, implants are used to anchor a partial or full prosthesis extending over a number of tooth positions in the same or different quadrants, etc. The embodiment depicted in FIG. 8 provides a prosthetic device 66c covering the lower front teeth positions, i.e., the four incisor teeth and the two adjacent canine teeth. In this embodiment, four implants 10 are used, to for the two center incisor teeth positions and one each for the canine teeth positions. The embodiment depicted in FIG. 9 provides a prosthetic device 66d, similar to the prosthetic device 66c shown in FIG. 8, covering the lower front teeth positions, i.e., the four incisor teeth and the two adjacent canine teeth. In FIG. 9 embodiment, however, six implants 10 are used, one for each of the incisor teeth positions and canine teeth positions. The implants 10 in the FIGS. 8 and 9 embodiments are similar to the implants illustrated in FIGS. 1 and 3-4, and are installed as described above.

Dental implants 10 and 10a illustrated in FIGS. 1 and 2 are for prosthetic devices of the fixed type. However, dental implants according to embodiments of the invention may also be used for removable dental prosthetic devices. FIG. 10 illustrates a one post embodiment of a dental implant 10b for a removable prosthetic device, e.g., a cap. In a one-post embodiment, e.g., for insertion at a tooth location formerly occupied by a single root tooth (which may be referred to as a mini-implant), the dental implant comprises at least one post 12a, and a stabilizer 14. The upper portion 26a of the post 12a terminates in a ball 57. The implant 10b is similar to the one post implant illustrated in FIGS. 1 and 3, except that the fastener system comprises the ball 57 which bears against the top surface 15 of the platform 14. The post 12a is inserted through a stabilizer 14 and threaded to the jawbone, with the ball 57 bearing against the platform, to secure the post and the stabilizer and to load the stabilizer against the jawbone. The ball 57 and the removable implant may be conventional, e.g., the ball 57 includes a recess 58 to receive an o-ring 59 within a removable prosthetic device 60 which compresses when the removable prosthetic device is mounted over the ball to removably attach the prosthetic device to the post.

In the embodiments described above, the larger surface area provided by the platform and the loading of the platform against the jawbone provides a stable and permanent fixed base for single and multiple tooth implants. The use of a relatively thin post or posts can minimize the invasiveness of the procedure, both at a single root or multiple root tooth location, which can permit immediate loading of fixed prosthetic devices, enhance patient tolerance to the procedure, and reduce healing time.

Training time for professionals to perform the procedures describe above is expected to be relatively short, e.g., about two weeks.

As for implants in general, it is expected that not all patients will be candidates for the implants that embody the invention. However, for suitable candidates, although patient tolerance and healing with vary with patients, their age, state of health, etc., it is expected that the procedures for installing implants which embody the invention will be more easily tolerated and involve shorter healing periods, e.g., approximately two months.

While the invention has been described and illustrated in connection with preferred embodiments, many variations and modifications as will be evident to those skilled in this art may be made without departing from the spirit and scope of the invention as defined by the claims, and the invention is thus not to be limited to the precise details of methodology or construction set forth above as such variations and modifications are intended to be included within the scope of the invention as defined by the claims.