Biofunctional dental implant - Patent Review 7300282

The invention claimed is:

1. A dental implant for affixing a crown portion to a bone structure in the mouth of a patient, said dental implant comprising: a root portion to be implanted below the patient's gum line within an implant socket in the patient's bone structure, said root portion having a channel extending longitudinally therethrough; a flexible abutment projecting upwardly from said root portion, said flexible abutment having a plurality of flexible splines and a passageway extending longitudinally therethrough and being axially aligned with the channel extending longitudinally through said root portion; a crown portion including an elastomeric cap to surround said flexible abutment and a crown to surround said elastomeric cap; and an abutment post moving through said crown portion and into receipt by the axially aligned channel extending longitudinally through said root portion and the passageway extending longitudinally through said flexible abutment, said abutment post applying an outward pushing force against said flexible abutment by which to cause the plurality of flexible splines thereof to rotate towards and compress said elastomeric cap against said crown, whereby to hold said flexible abutment against the crown portion and thereby attach said crown portion to said root portion.

2. The dental implant recited in claim 1, further comprising a spline spreader located between the plurality of flexible splines of said flexible abutment, the movement of said abutment post through said crown portion forcing said spline spreader to slide along said plurality of flexible splines by which to generate said outward pushing force for causing said flexible splines to rotate towards and compress said elastomeric cap against said crown.

3. The dental implant recited in claim 2, wherein said abutment post has a relatively wide head at one end thereof, and each of said plurality of flexible splines of said flexible abutment has a sloping ridge running therealong, said relatively wide head of said abutment post forcing said spline spreader to ride over the sloping ridges of said plurality of flexible splines as said abutment post moves through said crown portion by which to generate said output pushing force against said flexible abutment.

4. The dental implant recited in claim 3, wherein said spline spreader has a hole extending therethrough and a plurality of slots located therearound, said abutment post moving through each of said crown portion and the hole through said spline spreader, such that the relatively wide head of said abutment post moves into engagement with said spline spreader for forcing said spline spreader to slide along the sloping ridges of said plurality of splines with each of said plurality of splines being received within a respective one of said plurality of slots.

5. The dental implant recited in claim 1, wherein said root portion includes a plurality of radially extending ports communicating with said longitudinally extending channel so that at least one of a human growth factor and an antibiotic can be delivered to the implant socket prior to said abutment posts moving through said crown portion and into receipt by said longitudinally extending channel.

6. The dental implant recited in claim 1, wherein said root portion has at least one bevel formed therein so as to be located at the gum line of the patient when said root portion is implanted within the implant socket.

7. The dental implant recited in claim 1, wherein said root portion has a series of screw threads extending therearound and a plurality of sharp barbs projecting outwardly therefrom, said screw threads and said barbs cutting into the patient's bone structure to anchor said root portion at the implant socket within which said root portion is implanted.

8. The dental implant recited in claim 1, wherein said root portion has at least one anti-rotational notch formed therein to engage the patient's bone structure and prevent a rotation of said root portion relative to the implant socket within which said root portion is implanted.

9. A dental implant for affixing a crown portion to the bone structure in the mouth of a patient, said dental implant comprising: a root portion to be implanted below the patient's gum line within an implant socket in the patient's bone structure, said root portion having a channel extending longitudinally therethrough; a flexible abutment detachably connected to and projecting upwardly from said root portion such that at least some of said flexible abutment is removably received within the longitudinally extending channel through said root portion, said flexible abutment having a passageway extending longitudinally therethrough and being axially aligned with the channel extending longitudinally through said root portion; a crown portion surrounding said flexible abutment; and an abutment post moving through said crown portion and into receipt by the axially aligned channel extending longitudinally through said root portion and the passageway extending longitudinally through said flexible abutment by which to detachably connect said flexible abutment to said root portion within said longitudinally extending channel thereof, said abutment post applying an outward pushing force against said flexible abutment by which to hold said flexible abutment against said crown portion and thereby attach said crown portion to said root portion.

10. The dental implant recited in claim 9, wherein said crown portion includes an elastomeric cap to surround said flexible abutment and a crown to surround said elastomeric cap, the outward pushing force applied against said flexible abutment by said abutment post causing said flexible abutment to compress said elastomeric cap against said crown.

11. The dental implant recited in claim 10, wherein said flexible abutment includes a plurality of flexible splines, the outward pushing force applied against said flexible abutment by said abutment post causing said flexible splines to rotate towards and compress said elastomeric cap against said crown.

12. The dental implant recited in claim 11, wherein said abutment post has a relatively wide head at one end thereof, and each of said plurality of flexible splines of said flexible abutment has a sloping ridge running therealong, the relatively wide head of said abutment post riding over the sloping ridges of said plurality of flexible splines as said abutment post moves through said crown portion by which to generate said outward pushing force against said flexible abutment for causing said flexible splines to rotate towards and compress said elastomeric cap against said crown.

13. The dental implant recited in claim 11, wherein the relatively wide head of said abutment post includes a tapered area that slides over the sloping ridges of said plurality of splines as said abutment post moves through said crown portion by which to generate said outward pushing force against said flexible abutment for causing said flexible splines to rotate towards and compress said elastomeric cap against said crown.

14. The dental implant recited in claim 9, wherein said root portion has at least one anti-rotational notch formed therein and at least one sharp barb projecting outwardly therefrom, said anti-rotational notch and said sharp barb engaging the patient's bone structure to prevent a rotation and the removal of said root portion relative to the implant socket within which said root portion is implanted.

15. A replacement crown assembly to be removably connected to an existing root portion that is implanted below a patient's gum line to complete a dental implant, said replacement crown assembly comprising: a flexible abutment to be connected to the existing root portion so as to project upwardly therefrom, said root portion having a screw threaded channel extending longitudinally therethrough and said flexible abutment having a passageway extending longitudinally therethrough and being axially aligned with the screw threaded channel through said root portion; an elastomeric cap surrounding said flexible abutment; a crown surrounding said elastomeric cap; and a removable abutment post having a screw threaded end rotated in a first direction through said elastomeric cap and the longitudinally extending passage of said flexible abutment for receipt by the screw threaded channel of said existing root portion by which to detachably connect said flexible abutment to said existing root portion, said abutment post applying an outward pushing force against said flexible abutment by which to cause said elastomeric cap to be compressed against said crown, the screw threaded end of said removable abutment post being rotated in an opposite direction out of said root portion and away from said flexible abutment by which said flexible abutment is disconnected from said existing root portion.

16. The replacement crown assembly recited in claim 15, wherein said flexible abutment includes a plurality of flexible splines, the outward pushing force applied against said flexible abutment by said abutment post causing said flexible splines to rotate towards and compress said elastomeric cap against said crown.

17. The replacement crown assembly recited in claim 16, wherein said abutment post has a relatively wide head at one end thereof, and each of said plurality of flexible splines of said flexible abutment has a sloping ridge running therealong, the relatively wide head of said abutment post riding over the sloping ridges of said plurality of flexible splines as said abutment post moves through the longitudinally extending passage of said flexible abutment by which to generate said outward pushing force against said flexible abutment for causing said flexible splines to rotate towards and compress said elastomeric cap against said crown.

18. The replacement crown assembly recited in claim 17, wherein the relatively wide head of said abutment post includes a tapered area that slides over the sloping ridges of said plurality of splines as said abutment post moves through the longitudinally extending passage of said flexible abutment by which to generate said outward pushing force against said flexible abutment for causing said flexible splines to rotate towards and compress said elastomeric cap against said crown.

19. A replacement crown assembly to be removably connected to an existing root portion that is implanted below a patient's gum line to complete a dental implant, said replacement crown assembly comprising: a flexible abutment to be connected to the existing root portion so as to project upwardly therefrom, said flexible abutment having a passageway extending longitudinally therethrough; an elastomeric cap surrounding said flexible abutment; a crown surrounding said elastomeric cap; a removable abutment screw moving through said elastomeric cap and the passage extending longitudinally through said flexible abutment for receipt by said existing root portion by which said flexible abutment is detachably connected to said existing root portion; and a locking nut coupled to and moving axially along said abutment screw for applying an outward pushing force against said flexible abutment by which to cause said elastomeric cap to be compressed against, said crown.

20. The replacement crown assembly recited in claim 19, wherein said flexible abutment includes a plurality of flexible splines, the outward pushing force applied against said flexible abutment by said locking nut causing said flexible splines to bend towards and compress said elastomeric cap against said crown.

21. The replacement crown assembly recited in claim 19, wherein a first end of said abutment screw and the interior of said locking nut are each threaded by which to enable said locking nut to be coupled to said first end and move axially therealong so as to apply said outward pushing force against said flexible abutment.

22. The replacement crown assembly recited in claim 21, wherein the opposite end of said abutment screw and the existing root portion are each threaded by which to enable said abutment screw to be coupled to said root portion for detachably connecting said flexible abutment to said root portion.

23. The replacement crown assembly recited in claim 22, wherein said abutment screw includes a relatively wide washer located between the threaded first and opposite ends thereof, said locking nut moving axially along said first end and into contact with said washer to prevent said abutment screw from leaning towards said flexible abutement.

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BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a biofunctional dental implant having a crown portion connected to a root portion by means of an abutment post. The advancement of the abutment post through a flexible abutment projecting upwardly from the root portion causes the flexible abutment to apply an outward pushing force against the crown portion for holding the crown portion atop the root portion without the use of screws or similar fastening devices.

2. Background Art

Natural teeth in the human mouth are supported in bone by periodontal fibers that function as shock absorbers when a compressive force is applied, such as during chewing. Through disease, accidental injury, anatomical abnormalities, age, and the like, a natural tooth may be removed or missing such that a dental appliance or prosthetic device (e.g., a crown) is implanted in the patient's bone structure to improve the patient's physical appearance and/or quality of mastication. However, problems such as crown breakage, screw loosening and screw breakage are inherent problems with the conventional crown implant.

More particularly, screws commonly associated with conventional crowns sometimes break because of over tightening and due to tension and lateral stress to which the crown is subjected during use. Moreover, a single crown can rotate in response to high lateral and torquing forces that are encountered while chewing, whereby to rotate and loosen screws. As dental professionals will understand, it is difficult and time consuming to retrieve and/or repair such broken screws. In addition, special purpose torque drivers are required to install these screws. Once the root portion of the implant is installed, it may take several months to achieve suitable bone integration of the root portion with the surrounding bone structure thereby resulting in increased loading time before the crown can be reliably attached. What is more, many crowns cannot easily absorb and distribute shock and other physical forces that are generated during chewing. Such crowns may be susceptible to damage or reduced life and may be unable to provide the function of a natural tooth and the quality of mastication associated therewith.

Accordingly, it would be desirable to overcome the problems associated with conventional crowns by avoiding screws which can break or loosen and eliminating the special purpose tools that are needed to install such screws. It would also be desirable to provide the crown with a shock absorbing cushion to better distribute the forces to which the crown will be subjected. It would be further desirable to have a replacement crown which is detachably connected to an existing root portion so that a new crown can be substituted for a defective or broken crown without requiring another surgery as well as the cost and patient discomfort associated therewith.

Reference may be made to my prior U.S. Pat. No. 5,890,902 issued Apr. 6, 1999 and pending patent application Ser. No. 10/159,644 filed Jun. 3, 2002 for examples of dental implants having a crown portion fixedly connected to a root portion.

SUMMARY OF THE INVENTION

A biofunctional dental implant is disclosed by which a crown portion is affixed to a root portion that is implanted below a dental patient's gum line within an implant socket that is formed in the patient's bone structure. The root portion may have one or more screw threads extending therearound, anti-rotational notches formed therein, and sharp edged barbs projecting therefrom by which to engage the patient's bone structure so as to anchor the root portion in place and prevent the root portion from rotating relative to the implant socket within which the root portion is located. A screw threaded channel runs longitudinally through the root portion and communicates with a set of radially extending ports so that a human growth factor and/or an antibiotic can be supplied to the implant socket within which the root portion is located. A flexible abutment stands upwardly from the top of the root portion. The flexible abutment has a plurality of flexible splines and a passageway that extends longitudinally between the splines. In the assembled configuration, the passageway extending through the flexible abutment is axially aligned with the channel extending through the root portion.

The crown portion includes a crown that is cemented over a metallic, ceramic or plastic coping. A shock absorbing elastomeric cap is positioned in surrounding engagement with the flexible abutment, and the combination crown and coping is positioned in surrounding engagement with the elastomeric cap. An abutment post having a threaded first end and a relatively wide head at the opposite end is advanced through the crown portion and into receipt by the axially aligned channel and passageway that extend longitudinally through the root portion and the flexible abutment, whereby the threaded end of the abutment post is moved into mating engagement with the screw threaded channel through the root portion.

In one embodiment, a spline spreader is positioned between the flexible splines of the flexible abutment for receipt of the threaded end of the abutment post. As the threaded end of the abutment post is advanced towards the root portion, the relatively wide head of the abutment post forces the spline spreader to slide over the flexible splines, whereby to generate a pushing force for causing the splines to rotate outwardly. Accordingly, the flexible splines compress the elastomeric cap against the crown and its coping to hold the crown portion atop the root portion.

In another embodiment, the flexible abutment is detachably connected to the top of the root portion so as to stand upwardly from a mounting hole formed therein. In this case, the relatively wide head of the abutment post has a tapered or angled area. The threaded end of the abutment post is advanced through the crown portion and into receipt by the axially aligned channel through the root portion and the passageway through the flexible abutment so as to connected the detachable abutment to the root portion. At the same time, the tapered area at the head of the abutment post slides over the flexible splines of the flexible abutment, whereby to generate the pushing force for causing the splines to rotate outwardly by which to compress the elastomeric cap against the crown portion and hold the crown portion atop the root portion.

In an additional embodiment, a replacement crown assembly is removably connected to an existing root portion that has been previously implanted within the patient's bone structure. A flexible abutment having a passageway extending longitudinally therethrough and a plurality of flexible splines is detachably connected to the existing root portion. The threaded end of a removable abutment post is advanced into receipt by the axially aligned channel through the root portion and the passageway through the flexible abutment so as to connect the detachable abutment to the existing root portion. The crown portion is located in surrounding engagement with the detachable flexible abutment. In this case, the relatively wide head of the removable abutment post is tapered. As the removable abutment post is advanced towards the root portion, the tapered head thereof slides over the flexible splines of the flexible abutment, whereby to generate the pushing force for causing the splines to rotate outwardly by which to compress the elastomeric cap against the crown portion and hold the crown portion atop the root portion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-section showing a root portion and a crown portion of a biofunctional dental implant according to a first preferred embodiment connected to one another and implanted within the bone structure in the mouth of a dental patient;

FIG. 2 is an exploded view of the dental implant shown in FIG. 1;

FIG. 3 is a cross-section of the root portion of the dental implant shown in FIG. 1;

FIG. 4 illustrates a top view of the root portion for the dental implant shown in FIG. 1;

FIG. 5 illustrates a side view of the root portion for the dental implant shown in FIG. 1.

FIGS. 6 and 7 illustrate a modification of the root portion for the dental implant shown in FIG. 1;

FIG. 8 is an exploded view showing a root portion and a crown portion to be detachably connected to one another to form a biofunctional dental implant according to another preferred embodiment;

FIG. 9 is an exploded view showing a replaceable crown portion to be detachably connected to an existing root portion to form a biofunctional dental implant according to yet another preferred embodiment;

FIG. 10 shows the replaceable crown portion of the dental implant of FIG. 9 detachably connected to the existing root portion;

FIG. 11 is a cross-section showing a replaceable crown portion and an existing root portion detachably connected to one another to form a biofunctional dental implant according to a further preferred embodiment;

FIG. 12 shows a detail to illustrate the detachable connection of the replaceable crown portion of the dental implant of FIG. 11 to the existing root portion.

FIG. 13 is an exploded view showing a replacement crown portion to be detachably connected to an existing root portion to form a biofunctional dental implant according to a still further preferred embodiment;

FIG. 14 is a cross-section showing the replaceable crown portion of the dental implant of FIG. 13 detachably connected to the existing root portion;

FIG. 15 shows a replaceable crown portion having a locking nut by which the crown portion is detachably connected to an existing root portion of the type shown in FIG. 11; and

FIG. 16 shows details of the locking nut of FIG. 15.

DETAILED DESCRIPTION

Referring initially to FIGS. 1-5 of the drawings, there is shown a biofunctional dental implant 1 which forms a first preferred embodiment of this invention. Dental implant 1 is suitable for use in the mouths of both humans and animals. The implant 1 includes a root portion 3 that is preferably manufactured from a biocompatible metallic (e.g., titanium or titanium alloy) or ceramic material that is adapted to be implanted and locked in the bone structure of a dental patient. The root portion 3 has a tapered implant casing 5 including a series of sharp edged barbs 7 extending around the exterior thereof and a set of screw threads 6 formed at the interior along a longitudinally extending channel 12. As is best shown in FIG. 1, the implant casing 5 of root portion 3 is installed within an implant socket that is made in the patient's bone structure so as to be able to support a crown portion (designated 40) above the gum line. The peripheral barbs 7 of implant casing 5 enable the root portion 3 of dental implant 1 to cut into the patient's bone structure during installation and then provide resistance against the root portion being accidentally pulled out of the implant socket. One or more anti-rotational notches 9 (best shown in FIGS. 2, 3 and 5) run axially along a side of the implant casing 5 to allow a subsequent growth of the patient's bone to mechanically lock and prevent a rotation of the root portion 3 following installation.

Vertical rows of radially extending channels and/or ports 10 are spaced around the implant casing 5. The longitudinally extending channel 12 through implant casing 5 communicates with the radially extending ports 10 and an axially aligned apical port 13. In this manner, human growth factor 14 can be delivered to and evenly distributed around the implant socket during installation so as to promote tissue growth over the root portion 3. In this same regard, the longitudinally extending channel 12 and the radially and axially extending ports 10 and 13 also cooperate to deliver to the implant socket an antibiotic (e.g., a bacteriacidal, such as chlorhexidine) or other fluids for the purposes of irrigation and aspiration and/or to treat bacterial lesions. By virtue of the foregoing, the necessity for a subsequent surgery might be avoided as a consequence of an otherwise untreated infection following installation of dental implant 1.

The top of the implant casing 5 of root portion 3 includes a flat head 16 that is located within the patient's bone structure so as to lie flush with the patient's gum line. A bevel 18 (best shown in FIGS. 2-4) is formed at opposite sides of the head 16 of the implant casing 5 in order to provide the root portion 3 with a scallop to better match the contour of and mate with the patient's surrounding tissue.

Projecting upwardly from the head 16 of implant casing 5 is a hollow cylindrical abutment 20. The cylindrical abutment 20 includes a plurality of (e.g., four) flexible splines 22 having a spring-like memory that are evenly spaced from one another. Each of the flexible splines 22 of abutment 20 has a sloping locking ridge 24 that runs vertically therealong. A set of locking grooves 26 extends circumferentially around the splines 22 of cylindrical abutment 20. The function of the locking ridges 24 and locking grooves 26 of abutment 20 will soon be explained.

Seated upon the flat head 16 of the root portion 3 of dental implant 1 is a cap 28 that is preferably manufactured from an elastomeric material. A (e.g., cylindrical) passage 30 runs longitudinally through the cap 28. A flexible sealing skirt 32 flares outwardly from the bottom of elastomeric cap 28. In the assembled configuration of the dental implant 1 shown in FIG. 1, with the cap 28 seated atop the flat head 28, the cylindrical abutment 20 is received through the cylindrical passage 30 formed in cap 28. The circumferentially extending locking grooves 26 around the splines 22 of abutment 20 will create a gripping surface with the cap 28 to prevent the inadvertent removal of cap 28 from the head 16 of root portion 3. Moreover, the flexible sealing skirt 32 of elastomeric cap 28 will be located at the junction of the root portion 3 and the soon to be described crown portion 40 so as to block the movement of fluids, food particles, and other possible contaminants towards the implant socket within which the dental implant 1 is anchored.

With the elastomeric cap 28 seated atop the flat head 16 of the implant casing 5, the crown portion 40 is positioned over cap 28. The crown 40 includes a hollow body that is preferably manufactured from a porcelain or metallic material. As is best shown in FIG. 1, the hollow crown portion 40 is provided with an internal liner, often referred to as a coping 42. The coping 42 is preferably manufactured from a ceramic or metallic material and is shaped to formed a close fit with the elastomeric cap 28 to lie thereunder. The crown portion 40 is typically cemented to the coping 42.

Each of the hollow crown portion 40 and the coping liner 42 are provided with a mounting opening 43 through which to receive the elastomeric cap 28 and an opposing installation opening 44 that is coaxially aligned with the mounting opening 43 and the cylindrical passage 30 through cap 28. To enable the combination crown portion 40 and coping 42 to be reliably connected to the root portion 3 in surrounding engagement with the elastomeric cap 28 atop the flat head 16 of implant casing 5, a rigid abutment screw 46 is provided. A series of screw threads 47 are located around one end of the abutment screw 46, and a relatively wide head 48 is formed at the opposite end. The head 48 of abutment screw 46 is provided with a (e.g., hex shaped) hole to receive a correspondingly shaped tool that is adapted to impart a rotational force to cause the abutment screw 48 to move inwardly of the implant casing 5 of the root portion 3 of dental implant 1.

During installation, one or more O-rings 50 are located within peripheral grooves 52 that are formed around the abutment screw 46. The threaded end 47 of abutment screw 46 is moved into a through hole 53 in a spline spreader 54 for receipt by the hollow abutment 20 of the implant casing 5 via the installation opening 44 in crown portion 40 and the cylindrical passage 30 in cap 28. The spline spreader 54 is provided with a number of (e.g., four) evenly spaced slots 56 that correspond to the number of flexible splines 22 of the abutment 20. The spline spreader 54 is dimensioned so as to fit between the flexible splines 22 of the abutment 20 (best shown in FIG. 1), whereby the vertical locking ridges 24 running along the sloping splines 22 are received by respective slots 56 in the spline spreader 54.

As the abutment screw 46 is tightened down against the root portion 3 and the screw threads 47 of abutment screw 46 are axially advanced past the abutment 20 and along the internal screw threads 6 of the longitudinally extending channel 20 of implant casing 5 (also best shown in FIG. 1), the spline spreader 54 carried by abutment screw 46 will ride over and apply a pushing force against the vertical locking rides 24 along the flexible splines 22 of abutment 20. The receipt of the spline spreader 54 by abutment 20 will cause the flexible splines 22 thereof to bend or rotate outwardly toward the elastomeric cap 28. Accordingly, the elastomeric cap 28 is compressed against the crown portion 40 and the coping 42 therewithin, whereby to hold the crown portion 40 against the root portion 3 of dental implant 1. Moreover, the elastomeric cap 28 will provide a resilient or cushion interface to minimize the transfer of shock between the crown and root portions 40 and 3 of dental implant 1.

Once the threaded abutment screw 46 has been fully inserted within the implant casing 5 of root portion 3 such that the screw threads 47 of abutment screw 46 are mated to the internal screw threads 6 along the channel 12 of implant casing 5, an additional holding force is provided by which to connect the crown portion 40 to the root portion 3. At this point, an optional filler (e.g., an elastomeric material, or the like) can be used to close the installation opening 44 formed in the crown portion 40 through which the abutment screw 46 is inserted for receipt by the root portion 3. By virtue of the foregoing, an integral biofunctional dental implant is provided for human and animal use which is relatively easy to manufacture and which will not become easily separated from the patient's bone structure during use.

FIGS. 6 and 7 of the drawings show various modifications to the root portion 3 of the biofunctional dental implant 1 that was described while referring to FIGS. 1-5. As previously disclosed, the root portion 3 includes anti-rotational notches 9 that run axially along the implant casing 5 to prevent a rotation of the root portion following implantation of implant 1 in the patient's implant socket. The anti-rotational notches 9 can be replaced by or augmented with an optional set of sharp threads 60. The threads 60 extend around the implant casing 5 so as to coincide with the cortical portion of the patient's bone structure. The threads 60 cooperate with the barbs 7 of implant casing 5 to reliably anchor the root portion 3 within the bone structure so as to hold the root portion stationary following implantation.

In addition, the shape of the cylindrical abutment 20 may be changed to enhance the mating surface formed with the elastomeric cap 28 of FIGS. 1-5 that is to be seated on the flat head 16 of implant casing 5 in surrounding engagement with abutment 20. That is, the bottom of the abutment 20 is provided with an optional arcuate surface 62 to maximize the seal that is created by the receipt of the sealing skirt 32 of the cap 28 at the junction of the crown portion 40 and the root portion 3 in the manner shown in FIG. 1.

What is more, the square top of the cylindrical abutment 20 of FIGS. 1-5 is rounded in FIGS. 6 and 7. That is, each of the flexible splines 22 of abutment 20 is provided with an optional rounded tip 64, whereby to enhance the mating engagement of the elastomeric cap 28 around abutment 20.

FIG. 8 of the drawings shows other modifications to the dental implant 1 of FIGS. 1-5. The dental implant 1-1 of FIG. 8 includes a detachable cylindrical abutment 20-1 and eliminates the spline spreader (designated 54 in FIGS. 1-5). In particular, the one piece root portion 3 of FIGS. 1-5 is now replaced by the combination of a root portion 3-1 and a detachable abutment 20-1. The tapered implant casing 5, barbs 7, anti-rotational notches 9, human growth factor ports 10, flat head 16 and the bevels 18 formed therein are common to each of the root portion 3 and 3-1 of FIGS. 1-5 and 8 and, therefore, identical reference numerals had been used for each.

The implant casing 5 of root portion 3-1 is provided with a (e.g., hex shaped) mounting hole 68 formed at the top of the flat head 16. The mounting hole 68 is sized and shaped to accommodate a similar (e.g., hex shaped) base 70 of abutment 20-1. A plurality of (e.g., four) flexible splines 28 having a spring-like memory and respective sloping locking ridge 24 running vertically therealong project upwardly from base 70 at evenly spaced locations therearound. Locking grooves 26 are formed around the splines 22 so as to better grip the elastomeric cap 28 that is to be seated upon the flat head 16 of implantation 5 in surroundin