WO2007067105A1

WO2007067105A1 - A surgical tool for a dental implant procedure, a tool kit for a dental implant procedure and a method for making a dental implant

Info

Publication number: WO2007067105A1
Application number: PCT/SE2005/001872
Authority: WO
Inventors: Lars Jonsson; Per-Åke LARSSON
Original assignee: Lars Jonsson; Larsson Per-Aake
Priority date: 2005-12-08
Filing date: 2005-12-08
Publication date: 2007-06-14

Abstract

The invention relates to a surgical tool for making dental implants. The tool 1 comprises a hollow cylinder 2 with a plurality of cutting teeth 5. The tool can be fastened on a hand-piece and used to make a cavity in a patient's jaw. The invention also relates to a method for making dental implants and to a tool kit comprising the inventive surgical tool.

Description

A SURGICALTOOLFORADENTALIMPLANTPROCEDURE, ATOOLKIT FORADENTALIMPLANTPROCEDUREAND AMETHODFORMAKINGA DENTALIMPLANT FIELD OF THEINVENTION

The present invention relates to a surgical tool for a dental implant procedure. The tool is used to prepare a part of a patient's jaw for receiving an implant screw. The invention also relates to a tool kit that includes the surgical tool and to a method for making a dental implant.

BACKGROUND OF THE INVENTION

Persons that have lost one or several teeth may obtain new teeth through a procedure referred to as dental implantation, hi this procedure, a cavity is formed in a part of the patient's jaw where a new tooth is to be implanted. A screw is then fastened in the cavity and thereby to the jaw bone of the patient. Such screws are typically made of titanium. An artificial tooth (for example a tooth made by a plastic material or a ceramic material) may then be secured to the screw. Procedures for making dental implants are disclosed in, for example, US patent No. 6814575, US patent 5967777, US

2004/0219479 Al and US 2004/0219480 Al. When making a dental implant, it is important that the cavity is formed correctly, that the person performing the procedure is able to verify that the cavity has been correctly formed and to verify that the screw is correctly positioned. This may require the use of sophisticated x-ray equipment and such equipment may be expensive which in turn makes the dental implant procedure more expensive. An example of such equipment is disclosed in US patent No. 5431162. Equipment for x-ray tomography is intended to produce a three-dimensional picture of the patient's jawbone while the x-ray equipment that is used by an ordinary dentist is normally only capable of producing two-dimensional pictures (although pictures may be taken from different angles thereby giving an idea of three-dimensional form). The cost for tomographic equipment may be up to 10 times higher than the cost for x-ray equipment used by an ordinary dentist. If tomographic equipment is used, the cost for making a dental implant will thus become higher. In currently used procedures for making dental implants, it is further customary to uncover the jawbone itself i.e. to remove the flesh, before drilling in the bone. When the bone is surgically uncovered, this entails a certain risk for post-operative infections. Consequently, it may be necessary to use antibiotics. It is an object of the present invention to provide an alternative solution for making dental implants. It is also an objective of the invention to provide a method that is cost -effective and that requires less sophisticated x-ray equipment.

DISCLOSURE OF THE INVENTION

The invention relates to a surgical tool for a dental implant procedure, the tool comprising a first part shaped as a hollow cylinder having an upper end and a lower end, the lower end of the hollow cylinder having a plurality of cutting teeth such that the tool may function as an annular hole cutter. The cylinder has a maximum diameter of no more than 6mm. At the upper end of the hollow cylinder, there is a second part which is shaped to allow connection to a drive unit for rotating the tool. The second part is further shaped such that it may receive and guide an elongated instrument inserted through the second tool part and into the cylinder. The hollow cylinder may have an axial extension of 3mm - 15 mm. The wall of the hollow cylinder may have a thickness of, for example, 0,3 mm - 0,5 mm.

The second part of the tool may be provided with a shank which is coaxial with the cylinder and has a through-hole that may guide an elongate instrument.

The shank may have a polygonal outer surface and the through-hole in the shank a circular cylindrical surface.

The second part of the tool maybe shaped such that it forms a wall that closes the hollow cylinder except for a through-hole that can guide an elongated instrument such as a drill. The through-hole may be shaped in a shank that can be connected to a drive unit but the wall could also be provided with structure separate from the through-hole that enables a drive unit to be connected to the tool.

In one embodiment, at least a part of an interior surface of the hollow cylinder has an uneven surface

The invention also relates to a tool kit for a dental implant procedure. The tool kit comprises a surgical tool for dental implant procedures. The surgical tool has a body shaped as a hollow cylinder with a plurality of cutting teeth at one end of the hollow cylinder such that the surgical tool may function as an annular hole cutter and the tool is shaped so as to allow connection to a drive unit for rotating the surgical tool and guide structure such that an elongate element may be received by the surgical tool and guided into the hollow cylinder. The tool kit also comprises a first drill that fits the guide structure of the surgical tool and has an axial extension that exceeds the axial extension of the surgical tool. Additionally, the kit comprises a measuring rod that fits the guide structure of the surgical tool and a second drill having an outer diameter that is the same as the outer diameter of the hollow cylinder.

Optionally, the tool kit may comprise a tool-bit that has one end adapted to fit the surgical tool and another end that is adapted to fit a handpiece.

Optionally, the tool-kit may additionally also comprise an implant screw made of titanium. The implant screw could also be made of another material than titanium. For example, it could be made of a ceramic material comprising zirconium dioxide.

The method according to the invention comprises applying to a patient's jaw a surgical tool. The surgical tool is shaped as an annular hole cutter and the tool is used to make an annular hole in the patient' s j aw through the flesh in the j aw, the annular hole extending into a part of the j aw bone of the patient. Flesh and bone encapsulated by the surgical tool is removed such that a cavity is formed in the patient' jaw and an implant screw is fastened in the cavity that has been formed in the patient's jaw. The surgical tool may comprise guide structure and the method may further includes the steps of inserting a first drill through the guide structure of the surgical tool while the surgical tool is still embedded in the jaw bone and drilling a hole that is coaxial with the surgical tool, the hole extending deeper than the surgical tool. After the cavity has been formed, a second drill may be used to make the cavity deeper. The second drill has a diameter that is larger than the diameter of the first drill.

The method may include the use of a measuring rod that is inserted through the guide structure of the surgical tool after the first drill is applied. An x-ray picture may then be taken of the area of the jaw where the surgical tool is embedded.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows a side view of a surgical tool according to the present invention.

Fig. 2 is a cross-sectional view of the tool shown in Fig. 1

Fig. 3 is a view from above of the tool shown in Fig. 1.

Fig. 4 is a bottom view of the tool shown in Fig. 1

Fig. 5 is a view showing the surgical tool according to the invention in a position

immediately before it is applied to a part of a patient's jaw. Fig. 6 is a cross-sectional view showing the surgical tool in a position where it has penetrated into the jaw bone of a patient.

Fig. 7 is a cross-sectional view showing a first drill inserted through the surgical tool and drilled into the jawbone of the patient.

Fig. 8 is cross-sectional view showing how the first drill has been removed and a

measuring rod has been inserted into the hole created by the drill.

Fig. 9 shows how the surgical tool is removed and how flesh and bone encapsulated by the tool follows the tool such that a cavity is made in the jaw of the patient. Fig. 10 is a cross-sectional view showing how a second drill having a larger diameter than the first drill is used to make the cavity deeper.

Fig. 11 is a cross-sectional view showing an implant screw inserted into the jawbone of the patient.

Fig. 12 is a cross-sectional view similar to Fig. 11 but with a crown of a tooth applied. Fig. 13 shows a tool kit for a dental implant procedure.

Fig. 14 shows a detail of the tool kit.

Fig. 15 shows a detail of a second embodiment of the surgical tool.

DETAILED DESCRIPTION OF THE INVENTION

With reference to Figs. 1 - 4, the invention relates to a surgical tool 1 for a dental implant procedure. The tool comprises a first part 2 shaped as a hollow cylinder 2. The cylinder 2 has a maximum diameter of no more than 6mm. hi realistic embodiments of the invention, the outer diameter of the cylinder 2 may be 3mm - 6mm. The reason for this choice of dimension is that the tool 1 shall be applied to the jaw of a patient and the dimensions of a normal human jawbone would normally not allow diameters larger than 6 mm. The hollow cylinder 2 has an upper end 3 and a lower end 4. The lower end 4 of the cylinder 2 has a plurality of cutting teeth 5 such that the tool 1 may function as an annular hole cutter. At the upper end 3 of the hollow cylinder 2, there is a second part 7 that is shaped to allow connection to a drive unit for rotating the tool 1. The second part 7 is further shaped such that it may receive and guide an elongated instrument 13, 14 inserted through the second tool part 7 and into the cylinder 2.

In one embodiment, the second part of the tool 1 is provided with a shank 8 which is coaxial with the cylinder 2 and has a through-hole 9 that may guide an elongate instrument. The shank 8 may have a polygonal outer surface that allows a toolbit to obtain a firm grip on the shank 8 such that a handpiece to which the toolbit is connected can drive the tool 1 in a rotary motion. The through-hole 9 in the shank 8 may have a circular cylindrical surface allowing round objects to fit snugly in the through-hole 9. In Fig. 3, the polygonal surface is showed as being hexagonal. It should be understood that also other polygonal shapes can be contemplated, for example triangular or rectangular. The through-hole 9 may have a diameter of, for example, 2 mm. In the embodiments shown in Figs. 1 - 4, the surgical tool is made in one single piece such that the first part 2 and the second part 7 are integral with each other. However, embodiments of the invention can be envisaged where the second part of the tool 1 is formed by a separate piece that is detachably connected to the cylinder 2. For example, it could be screwed to the cylinder 2.

The hollow cylinder 2 will typically have an axial extension of 3mm - 15 mm. hi one realistic embodiment contemplated by the inventors, the axial extension of the hollow cylinder may be 11 mm. In another realistic embodiment contemplated by the inventors, the axial extension may be 6 mm. It should be understood that, to a high degree, the dimensions of the hollow cylinder are dependent on the dimensions of the patient's jawbone.

As indicated in Fig. 2, the wall of the hollow cylinder 2 has a thickness T. The thickness T of the wall may suitably be 0,3mm - 0,5 mm. hi one realistic embodiment

contemplated by the inventors, the wall thickness may be 0,3 mm. It is possible to envisage embodiments of the invention where the wall thickness exceeds 0,5 mm.

However, increasing wall thickness will make it more difficult to achieve a clean and neat cut. There is also a further reason why the wall should not be too thick. If the wall is relatively thin, frictional heat can more easily leave the tool and it is easier to cool the tool 1 if it is thin. The tool 1 should not become to hot during use since this may cause damage to the tissue of the patient's jaw-bone. The temperature should preferably not exceed 55⁰C since higher temperatures can cause damage to the bone. Specifically, higher temperatures may cause proteins in the bone to coagulate. The material used for the surgical tool 1 may be, for example, stainless steel. Stainless steel is resistant to corrosion and it is also a suitable material in view of sterilization procedures. Steel is also known to be a suitable material for tools that need to be sharp. hi the embodiment of Figs. 1 - 4, the second part 7 of the tool 1 forms a wall 10 that closes the hollow cylinder 2 except for the through-hole 9 that can guide an elongated instrument such as a drill 13. As best seen in Fig. 4, the cutting teeth 5 are sharpened at the end where the teeth 5 will meet flesh or bone, i.e. the thickness of the cylinder wall is reduced at the point where each cutting tooth 5 first meets the flesh or bone to be cut. Each cutting tooth 5 will thus have a leading face 30 which becomes narrower towards the lower end of the cylinder 2 (in this context, "lower" refers to what is the lower end in Fig. 1 and Fig. 2). As seen from the lower end of the surgical tool 1, the tool will thus have an appearance similar to, or substantially similar to, what is shown in Fig. 4. As can be seen in Fig. 1, Fig. 2 and Fig. 4, the teeth have substantially vertical leading faces 31 and inclined trailing faces or trailing sides 32 (the term "vertical" refers to what is vertical in Fig. 1 and Fig. 2 while "inclined" should be understood in a similar way). When the surgical tool 1 is used to make an annular hole, the tool is rotated in the direction of arrow A in Fig. 4. The inventors have found that the above described shape is suitable for a tool that should be able to cut efficiently through both flesh and bone and gives a neat and clean cut. However, other shapes for the cutting teeth 5 may also be considered. In the figures, six cutting teeth 5 have been indicated. However, it should be understood that more or less than six teeth could be used.

The use of the surgical tool 1 shall now be explained with reference to Figures 5— 12. It should be understood that, before the surgical procedure is started, an x-ray picture may be taken of the area where the surgical tool 1 is to be used. Such an x-ray picture may help a dentist or dental surgeon to determine whether it is at all possible to carry out the procedure and also to determine where and in which direction the surgical tool is to be applied. If an x-ray picture is taken before the procedure is initiated, this reduces the risk for the patient. However, embodiments of the invention can be envisaged where an x-ray picture is in fact not taken before the procedure begins.

In Fig. 5, a surgical tool 1 according to the present invention is brought towards the jaw 19 of a patient. The tool 1 is brought towards an empty area between two teeth 24 in the patient's jaw. The tool 1 may be mounted on a hand-piece 17, possibly via a tool bit 16. The hand-piece 17 can impart a rotary movement to the surgical tool 1. Due to the teeth 5 of the surgical tool 1, the tool 1 can be described in terms of an annular hole cutter. As indicated in Fig. 6, the surgical tool 1 is applied to a patient's jaw a surgical tool 1 and the tool 1 is used to make an annular hole in the patient's jaw 19 through the flesh 20 in the jaw and extending into a part of the jaw bone 21 of the patient. To prevent tissue damage caused by high temperatures, a cooling liquid may be applied to the tool 1 during this operation. As indicated in Fig. 1 - Fig. 3, embodiments of the invention are also possible where the exterior walls of the tool 1 are provided with channels 29 for cooling liquid. In one embodiment contemplated by the inventors, such channels 29 may have a depth of 0,1 mm and a width of 0,2 mm. Such cooling channels 29 can reduce the risk that the tissue in the jaw bone is damaged, hi Fig. 3, six cooling channels 29 are shown but it should be understood that the tool 1 may have less than six channels or more than six channels 29. For example, the tool 1 could have five cooling channels 29. One may also consider embodiments without cooling channels. In Fig. 1, the cooling channels 29 are shown as being straight and located between cutting teeth 5. It should be understood that the channels 29 could have other shapes. For example, they could be inclined relative to the vertical axis. The positioning of the channels 29 could also differ from what is shown in Fig. 1.

In an advantageous embodiment of the invention, a first drill 13 may then be inserted through the guide structure (through-hole 9) of the surgical tool 1 while the surgical tool 1 is still embedded in the jaw bone 21. As indicated in Fig. 7, the first drill 13 is then used to drill a hole that is coaxial with the surgical tool 1 and extends even deeper than the surgical tool 1 itself. The first drill 13 may suitably have a diameter that is the same as or slightly less than the diameter of the through-hole 9 in the surgical tool 1. The through-hole 9 can then reliably guide the first drill 13. In this context, it should be understood that the through-hole 9 may suitably have a length of at least some millimeters.

As indicated in Fig. 8, the first drill 13 has been removed and a measuring rod 14 has been inserted. The measuring rod may be provided with markings that allow the dentist or dental surgeon to determine exactly the depth of hole that has been drilled by the first drill 13. An x-ray device of the kind that is commonly used by an ordinary dentist may then be used to take an x-ray picture of the part of the jaw where the surgical tool 1 is embedded and the measuring rod 14 is located. The dentist or dental surgeon can then use the x-ray picture to determine if the surgical tool 1 and the hole drilled by the first drill 13 have been made correctly. The x-ray picture can also be helpful in documenting the procedure. If the x-ray shows that the surgical tool 1 is in an incorrect position, the dental implant procedure can be interrupted at this stage.

As indicated in Fig. 9, the surgical tool 1 is then removed. Frictional forces will cause flesh and bone 22 inside the cylinder 2 to be tightly gripped by the surgical tool 1. This can actually have the result that a piece 22 of flesh and/or bone that is encapsulated by the cylinder 2 is broken away from the jaw 19 of the patient when the surgical tool 1 is removed. This situation is illustrated in Fig. 9 where such a piece 22 actually follows the tool 1 when it is removed. If the piece 22 that is encapsulated by the cylinder 2 does not automatically follow the tool 1, the piece 22 of flesh and/or bone can easily be removed with for example a tweezer which has been experimentally confirmed on a jaw bone taken from an animal. Optionally, bone from the piece 22 can be used as filling material in the patient's jaw if there is a need for this. Today, synthetic materials are used for this purpose and the use of the patient's own bone may be preferable to such synthetic materials, both in view of cost and in view of possible negative bodily reactions to synthetic materials. When the surgical tool 1 and the piece 22 have been removed from the patient's jaw 19, a cavity 26 remains in the patient's jaw. A smaller cavity 27 coaxial with the cavity 26 remains as a result of the drilling that was performed with the first drill. As indicated in Fig. 10, a second drill 15 can then be used to make the cavity 26 deeper. The second drill 15 has a diameter that is larger than the diameter of the first drill 13. The outer diameter of the second drill 15 may be equal to the outer diameter of the surgical tool 1. The hole 27 made by the first drill can be used for a correct centering of the second drill 15.

Once the cavity 26 has been made sufficiently deep by the second drill 15, an implant screw 18 may be secured in the cavity 26 in a way that is conventional and known to those skilled in the art to which the invention pertains. The implant screw may be, for example, a titanium screw. Suitable screws 18 for this purpose may be obtained from, for example, Nobel Biocare Norden AB, Box 5211, SE-402 24 Gδteborg, Sweden.

However, other manufacturers also offer screws that could be used for this purpose. Other materials than titanium could be considered for the implant screw. For example, the implant screw could be made in a material comprising 95 % zirconium dioxide and

5% yttrium oxide.

It should be understood that, while the use of the first and second drills 13, 15 entail certain advantages, one could in fact envisage embodiments of the invention where no drill is used at all. It should also be understood that it is possible to envisage

embodiments of the invention where no separate measuring rod 14 is used. In such embodiments, an x-ray picture could be taken when the first drill 13 is still in the surgical tool 1 and embedded in the jaw of the patient. The first drill 13 would then serve the same purpose as a measuring rod 14. If the dentist or dental surgeon that carries out the procedure is experienced and skilful, this may be sufficient. One could also envisage embodiments where the second drill 15 is used but no first drill 13. In such embodiments, the through-hole 9 in the tool 1 could be avoided. However, it is considered preferable that the first drill 13 is in fact used. When the first drill 13 is used, the heat developed during drilling is not so great since the diameter of the first drill 13 is smaller than the diameter of the second drill 15. When the second drill 15 is applied, some tissue has already been removed by the first drill 13. Consequently, the second drill 15 does not generate so much heat as it would otherwise have done. Moreover, the hole or cavity 27 created by the first drill 13 serves as a guide when the second drill 15 is applied. As indicated in Fig. 10 and Fig. 13, the second drill 15 may have a pointed end 31 that can fit the cavity 27 such that the second drill is thereby guided (in this context, it should be understood that the drawings of the drills 13, 15 are only intended to give a schematic representation of the drills and that this schematic representation is not necessarily realistic in its details).

The inventors have compared a tool 1 where the wall thickness of the hollow cylinder 2 was 0,5 mm to a tool where the wall thickness was 0,3 mm. The inventors found that better results were achieved when the wall thickness was 0,3 mm. When the wall thickness was reduced from 0,5 mm to 0,3 mm, a more neat and clean cut was achieved.

The invention also relates to a tool kit 28 for a dental implant procedure. With reference to Fig. 13, the tool kit comprises a surgical tool 1 for dental implant procedures and having a body shaped as a hollow cylinder 2 with a plurality of cutting teeth 5 at one end of the hollow cylinder such that the surgical tool 1 may function as an annular hole cutter. The tool 1 is shaped so as to allow connection to a drive unit 16, 17 for rotating the surgical tool 1. The tool 1 also has guide structure 9 such that an elongate element 13, 14 may be received by the surgical tool 1 and guided into the hollow cylinder 2. The tool kit 28 also comprises a first drill 13 that fits the guide structure 9 of the surgical tool 1 and has an axial extension that exceeds the axial extension of the surgical tool 1. The tool kit further includes a measuring rod 14 that fits the guide structure 9 of the surgical tool 1 and a second drill 15 that has an outer diameter that is the same as the outer diameter of the hollow cylinder 2 or at least larger than the diameter of the first drill 13. In Fig. 13, the tools of the tool kit 28 are shown positioned on a tray 32 having a cavity for each tool. The tray 32 may optionally be enclosed by a flexible cover or the tray may have a hinged lid (not shown). The tool kit may optionally comprise a tool-bit 16 that has one end adapted to fit the surgical tool 1 and another end that is adapted to fit a handpiece 17. The tool-bit 16 is also shown in more detail in Fig. 14. hi Fig. 14, it can be seen how the tool-bit 16 has an inner cavity of hexagonal shape that has dimensions corresponding to a hexagonal outer surface of a shank on the surgical tool 1. In this way, the tool bit 16 can get a firm grip on the shank of the surgical tool. Of course, if the shank is of another shape than hexagonal (e.g. rectangular), the cavity of the tool-bit would have to have a

corresponding shape (e.g. rectangular). To reduce the risk that the surgical tool 1 falls off the tool bit 16, the tool bit 16 may be provided with a magnet to hold the surgical tool 1. Alternatively, some other holding means may be used. Optionally, the tool kit may additionally comprise an implant screw 18 made of titanium. It should be understood that the implant screw could be made of another material then titanium. It is possible to envisage embodiments of the tool kit that do not include a measuring rod. It is also possible to envisage embodiments that do not include the second drill 15. For example, the tool kit could be limited to the surgical tool 1 and the first drill 13. In another embodiment, the tool kit could be limited to the surgical tool 1, the first drill 13 and the second drill 15. In yet another embodiment, the tool kit could be limited to the surgical tool 1, the first drill 13, the second drill 15 and a tool bit 16.

With reference to Fig. 15 and Fig.16, two alternative embodiments of the surgical tool 1 shall now be explained. In Fig. 15, the hollow cylinder 2 of the surgical tool 1 is closed by a wall 10 in which there is a through-hole 9 that can serve as a guide for a drill or a measuring rod. However, there is no shank that can be gripped by a tool-bit or handpiece. Instead, the wall 10 of the surgical tool 1 is provided with structure 11 that is separate from the through-hole and that enables a drive unit 13, 14 to be connected to the tool 1. In Fig. 15, this structure is shown as additional holes 11 located at a radial distance from the through-hole 9. A suitably designed tool-bit could have projections fitting the openings 11 and enable the tool 1 to be driven by a hand-piece through the suitably designed tool-bit. Of course, it should be understood that other variations are also possible. For example, there could be parts projecting out from the wall 10 at the location where holes are indicated in Fig. 15. Such projections could fit cavities in a tool-bit or a hand-piece.

Another embodiment will now be explained with reference to Fig. 16. In the

embodiment according to Fig. 16, a part 12 of the interior wall of the cylinder 2 could be provided with an uneven surface. For example, it could have a rough surface or it could be provided with a thread or corrugation. It is believed by the inventors that such a design could increase the likelihood that a piece 22 of flesh and/or bone follows the tool 1 directly when the tool is removed from the jaw of the patient. The invention makes it possible to use less sophisticated x-ray equipment. Of course, it should be understood that the method could also be used together with very

sophisticated and expensive x-ray equipment but the method has the potential to make dental implants less expensive.

It is also an advantage of the present invention that it becomes possible to make a hole in the jaw-bone of a patient without previously removing the flesh from the jaw-bone. This means that complicated surgery can be avoided and an dental implant can be made by an ordinary dentist.

Thanks to the invention, it becomes possible to follow and document the entire process with standard x-ray equipment.

If several surgical tools 1 according to the present invention are used, it becomes (by using x-ray and the measuring rod 14) possible to see the positions for the fixtures of the whole jaw before final drilling is made.

The surgical tool 1 according the present invention is used to obtain optimal positioning of the implant. Use of the tool can thereby reduce the risk that adjacent teeth in the patient's jaw are damaged and also reduce the risk that underlying nerves and/or bloodvessels are damaged.

The invention also makes it possible to reduce the time required for making a dental implant. This also contributes to cost reduction.

The invention may also contribute to an aesthetically pleasing result since use of the inventive tool means that it is easier to prevent that the screw threads of the implant screw can be seen from the outside. While the invention has been described above with reference to a surgical tool, a tool kit and a method for making a dental implant, it should be understood that these categories only reflect different aspects of the same invention. Consequently, the claimed method may comprise such steps that would be the natural consequence of using the inventive tool or the inventive tool kit.

Claims

1) A surgical tool (1) for a dental implant procedure, the tool comprising:

a) a first part (2) shaped as a hollow cylinder (2) having an upper end (3) and a lower end (4), the lower end (4) of the hollow cylinder (2) having a plurality of cutting teeth (5) such that the tool (1) may function as an annular hole cutter, the cylinder (2) having a maximum diameter of no more than 6mm; and

b) at the upper end (3) of the hollow cylinder (2), a second part (7) being shaped to allow connection to a drive unit (16, 17) for rotating the tool (1) and the second part (7) further being shaped such that it may receive and guide an elongated instrument (13, 14) inserted through the second tool part (7) and into the cylinder (2).

2) A surgical tool (1) according to claim 1, wherein the second part of the tool (1) is provided with a shank (8) which is coaxial with the cylinder (2) and has a through- hole (9) that may guide an elongate instrument.

3) A surgical tool (1) according to claim 2, wherein the shank (8) has a polygonal outer surface and the through-hole (9) in the shank has a circular cylindrical surface.

4) A surgical tool according to claim 1, wherein the hollow cylinder (2) has an axial extension of 3mm - 15 mm.

5) A surgical tool (1) according to claim 1, wherein the second part (7) of the tool (1) forms a wall (10) that closes the hollow cylinder (2) except for a through-hole (9) that can guide an elongated instrument such as a drill (13) and wherein the wall (10) is provided with structure (11) separate from the through-hole that enables a drive unit (13, 14) to be connected to the tool (1). 6) A surgical tool according to claim 1, wherein at least a part of an interior surface of the hollow cylinder (2) has an uneven surface

7) A tool kit (28) for a dental implant procedure, the tool kit comprising:

a) a surgical tool (1) for dental implant procedures having a body shaped as a

hollow cylinder (2) with a plurality of cutting teeth (5 at one end of the hollow cylinder such that the surgical tool (1) may function as an annular hole cutter and the tool (1) being shaped so as to allow connection to a drive unit (16, 17) for rotating the surgical tool (1) and guide structure (9) such that an elongate element (13, 14) may be received by the surgical tool (1) and guided into the hollow cylinder (2);

b) a first drill (13) that fits the guide structure (9) of the surgical tool (1) and has an axial extension that exceeds the axial extension of the surgical tool (1);

c) a measuring rod (14) that fits the guide structure (9) of the surgical tool (1); and d) a second drill (15) having an outer diameter that is the same as the outer

diameter of the hollow cylinder (2). 8) A tool kit according to claim 7, wherein the tool kit additionally comprises a tool-bit (16) that has one end adapted to fit the surgical tool (1) and another end that is adapted to fit a handpiece (17).

9) A tool kit according to claim 7, wherein the tool kit additionally comprises an

implant screw (18) made of titanium.

10) A method for making a dental implant, the method comprising the steps of:

a) applying to a patient's jaw a surgical tool (1) shaped as an annular hole cutter using the tool (1) to make an annular hole in the patient's jaw (19) through the flesh (20) in the jaw and extending into a part of the jaw bone (21) of the patient; b) removing flesh and bone (22) encapsulated by the surgical tool such that a cavity (26) is formed in the patient' jaw; and

c) fastening an implant screw (18) in the cavity (26) that has been formed in the patient's jaw.

11) A method according to claim 10, wherein the surgical tool (1) comprises guide

structure (9) and the method further includes the steps of inserting a first drill through the guide structure of the surgical tool while the surgical tool (1) is still embedded in the jaw bone (21) and drilling a hole that is coaxial with the cutter that extends deeper than the surgical tool and, after the cavity (26) has been formed, using a second drill (15) to make the cavity (26) deeper, the second (15) drill having a diameter that is larger than the diameter of the first drill (13).

12) A method according to claim 11, wherein a measuring rod (14) is inserted through the guide structure of the surgical tool (1) after the first drill (13) is applied and an

X-ray picture is taken of the area of the jaw where the surgical tool (1) is embedded.