WO1999038450A1

WO1999038450A1 - Drill for making bore holes in bone tissue

Info

Publication number: WO1999038450A1
Application number: PCT/DE1999/000273
Authority: WO
Inventors: Axel Kirsch; Walter Dürr
Original assignee: Axel Kirsch; Duerr Walter
Priority date: 1998-02-02
Filing date: 1999-02-02
Publication date: 1999-08-05
Also published as: DE19803998A1; ATA901499A; DE19803998C2; AT411567B; AU2825599A

Abstract

The invention relates to a drill for making a bore hole in bone tissue. The inventive drill comprises a retaining part and a drill mount which is detachably connected to said retaining part via a coupling device. The invention is characterized in that the coupling device has a shaft arranged on one of two parts, and has a sleeve with a bore hole, said bore hole being complementary to the shaft, arranged on the other part. The shaft can be inserted into said bore hole. In addition, the inventive drill has a safety device provided for preventing a relative movement between the retaining part and the drill mount. Once assembled, the shaft engages inside the bore hole and the drill mount is secured on the retaining part. The retaining part and the drill mount each have a coolant bore hole provided for delivering a coolant, whereby the coolant bore hole of the one part has an opening in the bore hole of the sleeve, and the coolant bore hole of the other part has an opening in the area of the respective section of the shaft which is accommodated in the sleeve in a coupled state such that a coolant connection is produced for delivering coolant from the retaining part to the drill mount.

Description

Drills for making holes in bone tissue

This invention relates to a drill for producing bores in bone tissue, in particular for producing an implant bed in a jaw bone for inserting a dental implant. Such drills must be permanently cooled during use, since heating the bone tissue would lead to necrosis during drilling. The coolant in such drills is fed through a central cooling hole which passes through the drill and is connected to the coolant supply in the holder of the drilling device. The introduction of such a coolant bore, which typically has a diameter of 0.8 mm, to a length of typically 20 to 30 mm is very complex, which is reflected in the cost of such a drill. - 2 -

On the other hand, the actual drilling tool is a wearing part and must be retired after a certain period of time. With the known constructions, the entire drill had to be replaced.

Trephine drills are known which, as the drilling section, have a cylinder with saw teeth at the lower end, which is detachably connected to a holding part in order to enable the removal of a sawn-out bone cylinder. In these known trepan drills, the end of the holding part and the end of the drilling cylinder, which are to be connected to one another, each have the same diameter and are provided with an external thread. For assembly, the drilling cylinder is attached to the holding part, and a lock nut is screwed onto the external thread of the two joined ends in such a way that the two parts are held together. However, this type of connection is difficult to handle, especially if the drilling tools have to be replaced when drilling a hole, as is the case e.g. in the manufacture of implant beds or bone extraction for a biopsy.

It is the object of the invention to provide a drill for making a hole in bone tissue, which drill is more economical to manufacture and operate and is easy to handle.

This object is achieved according to the invention by a drill for producing a hole in a bone tissue with a holding part and a drilling attachment, which can be releasably connected to the holding part, and with a coupling device for connecting the holding part to the drilling attachment, which has a shaft on one of the two Parts and a sleeve with a complementary to the shaft bore on the other of the two parts, the shaft insertable into the bore substantially without lateral play - 3 -

is, and further includes a fuse for preventing relative movement between the holding part and the machining part, such that in the coupled state, the shaft engages in the bore and the drill bit is secured to the holding part.

It is preferably provided that the holding part and the drill attachment each have a coolant bore for the passage of a coolant, a coolant bore of one part having an opening in the bore of the sleeve and a coolant bore of the other part having an opening in the region of that part of the shaft which in the Coupled state is received in the sleeve, such that in the coupled state, a coolant connection for supplying coolant from the holding part to the drilling attachment is formed, which then essentially consists of the coolant bores of the holding part and the drilling attachment and possibly a part of the bore of the sleeve consists. The coupling device is set up in such a way that essentially all coolant which is supplied via the bore of the holding part is introduced into the bore of the drill attachment. Here, the bore in the drill attachment can have a larger diameter than the bore of the holding part. At least the coolant bore of the holding part preferably has an elongated shape.

The mouths of the bores are preferably aligned in the coupled state. In principle, however, a coolant channel can also be formed in the shaft and / or the sleeve, which connects the two mouths. The two coolant bores are preferably continuous bores running in the longitudinal direction of the holding part, which open into the bottom of the sleeve or the end face of the shaft and face each other in the coupled state. The coolant can be introduced into the coolant bore of the holding part via a cannula. However, the coolant bore of the holding part can also be fixed with a coolant supply be connected to the drill when the holding part forms an integral part of the drill.

According to the invention it can be provided that the securing device has at least one latching element on one of the two parts (holding part or drilling attachment) and an associated recess on the other of the two parts for the positive connection of the holding part and drilling attachment, which in the secured state carries the part carrying the sleeve a location of the shank supporting part that is outside the bore of the sleeve on the side of the cutting area of the drill when the shank is inserted into the bore. This locking element is preferably elongated, the longitudinal direction being parallel to the longitudinal axis of the drill.

To secure against rotation, the shaft and the bore can be designed in a complementary polygonal shape and a security against relative movement in the longitudinal direction, for example in the form of a clip, a spring clip or the like. exhibit. According to a preferred embodiment, however, the shaft and the bore are cylindrical.

According to the invention it can be provided that the coupling device has a positive locking device for securing against a relative rotational movement between the holding part and the drill bit, which has at least one spring tongue on one of the two parts and a recess for receiving at least part of the free end of the spring tongue, wherein the spring tongue is preferably biased so that its free end presses into the recess when it is received in the recess.

It can be provided that at least one spring tongue on one of the two parts has a locking head and the other part has a groove for receiving at least a part of the - 5 -

Free end of the spring tongue, which is provided with a recess for receiving the locking head, which is arranged so that the locking head can engage in the recess when the shaft is inserted into the bore and the spring tongue, at the end of which the locking head is located , is at least partially received in the groove, the depression being preferably arranged at the end of the groove. The recess for receiving the locking head can be designed as a groove running essentially in the circumferential direction of the holding part or the drilling attachment on a limited area of the circumference, but preferably as a circumferential annular groove in a plane perpendicular to the longitudinal axis.

In this way, the drilling attachment or the holding part is secured by the spring tongue and the complementary groove both against rotation (direction of movement transverse to the longitudinal direction of the spring tongue or of the groove) and against relative movement in the longitudinal direction (direction of movement in the longitudinal direction of the spring tongue).

Furthermore, a sliding sleeve, which is preferably attached to the holding part, can be provided, which is arranged such that it can be pushed over the latching element or the latching elements into a securing position, in such a way that the latching element (s) is held in the recess or the recesses. when the sliding sleeve is in the securing position.

The sliding sleeve can be preloaded into the securing position by a spring.

According to the invention it can further be provided that the sliding sleeve is detachably mounted.

For this purpose, the sliding sleeve can be screwed to a threaded ring which is opposite the holding part or the drilling - 6 -

Attachment is slidably mounted in the longitudinal direction, wherein the threaded ring has a device for preventing a rotational movement relative to the drilling attachment or the holding part.

This device preferably consists of bores, each of which can be brought to cover with a continuous bore in the part which holds the threaded ring, so that the threaded ring can be inserted through one or more retaining pins or the like. can be blocked.

According to the invention, the securing device can have a spring ring with a plurality of elastic spring tongues, which is at least partially surrounded by the sliding sleeve in the securing position.

The holding part is preferably provided with a further coupling part for coupling to a driven holder of a drilling device, but can also be firmly connected to a drilling device or form part of the same.

According to the invention, a drill system is provided in which the individual components, i.e. the holding part and the drill attachment can be replaced independently of one another.

In particular, a drill attachment for making a hole in bone tissue is provided, which has a coupling device for connection to a correspondingly designed holding part such that a drill is formed as described above.

Likewise, a holding part for receiving a drill bit for making a hole in bone tissue at one end and for connecting to a drill at its other end, which a coupling device for connecting to a correspondingly designed drill bit such that a drill is formed as described above.

In the embodiment in which the holding part is coupled to a drilling device, it can have a coupling device for releasable connection to a drilling device at the end which is opposite the coupling device for connection to the drilling attachment.

Finally, according to the invention, a drilling device for making bores in bone tissue is provided, which has a holding part as described above as a firmly connected component.

The two-part embodiment of the drill allows simpler manufacture, since the coolant hole no longer has to be drilled over the entire length of the drill. The shaft connection according to the invention allows the two parts to be plugged and released quickly, which is further favored by the securing system according to the invention with spring tongues and a sliding sleeve for securing the spring tongues.

Further features and advantages of the invention result from the following description of a preferred embodiment of the invention with reference to the accompanying drawings.

1 shows a partially sectioned overall view of a drill according to the invention,

2a shows a top view of a drill attachment according to the invention,

2b shows a partially broken away side view of a drill attachment according to the invention, - 8th -

3a shows a partially sectioned side view of the shaft of the holding part,

3b shows a top view of the shaft,

4 shows the spring ring placed on the shaft,

5a shows a sectional view of the clamping sleeve,

5b shows a top view of the adapter sleeve,

6 shows a top view of the threaded ring,

Fig. 7 shows a partial sectional view of the holding part according to the invention together with a tool for loosening the threaded ring.

The illustrated embodiment of the drill system according to the invention consists of a holding part 1 and a drill attachment 3 detachably connected to the holding part, which is shown in this exemplary embodiment as a cannon drill, but can also be a twist drill or another drilling tool suitable for producing bone bores. The holding part 1 has a shaft 5, which represents the base element of the holding part and is shown as an individual part in FIGS. 3a and 3b. At its right end in FIG. 1, this shaft 5 is equipped like a conventional drill with a cylindrical shaft 6 and a coupling 7 for insertion into the receptacle of a conventional drilling device. At the end opposite the coupling 7, the shaft is widened to form a cup-like sleeve 10 which has a bore 14 for receiving a complementary shaft 16 of the drill attachment 3. The shaft 6 has a cylindrical coolant bore 18 which opens into the bore 14 and can be connected at the opposite end in the area of the coupling 7 to a coolant supply of the drilling device. - 9 -

Typical dimensions of the coolant bore 18, to which the invention is, however, not restricted, are, for example, a length of 20 mm and a diameter of 0.8 mm. The bore 14 and the shaft 16 are dimensioned such that the shaft 16, when it is inserted into the bore 14, sits essentially without play in the latter and the front end 20 of the sleeve 10 on a shoulder 22 of the drill attachment at the end of the shaft 16 strikes. In this way, a perfect axial alignment of the drill with the shaft 6 and thus the drive shaft of the drilling device is guaranteed.

The shaft 16 has a central bore 24 which, when the drill bit 3 is inserted into the holding part 1, forms a continuation of the coolant bore 18, but with a somewhat larger diameter, and an opening 26 for delivering the coolant to the cutting area of the drill having .

To secure the drill bit against rotation and displacement relative to the holding part 1, a spring ring 30, shown in FIG. 4 as an individual part, with a plurality of spring tongues 32 is provided, at the end of which a locking head 34 is formed. This spring ring strikes on one side on a shoulder 36 of the shaft 5. The shaft 5 also has longitudinal grooves 37 which extend through the sleeve part

10 extend and in which the spring tongues 32 run, as can be seen from FIG. 1, an end region of the spring tongues

32 protrudes with the locking heads 34 beyond the edge 20 of the sleeve. In its coupling area, the drilling attachment 3 has longitudinal grooves 38 which can be brought into congruence with the longitudinal grooves 37 of the holding part. The depth of these grooves is designed so that the locking head 34 can only be inserted radially outward from the rest position by deflecting the spring tongues 32. The coupling area of the drill attachment 2 furthermore has an annular groove 40 which, in the exemplary embodiment shown, has the longitudinal grooves 38 - 10 -

crosses, but can also be arranged at the end or offset from these. This annular groove 40 is arranged and dimensioned such that the locking heads 34 can snap into this annular groove 40 and the areas of the spring tongues 32 projecting beyond the sleeve 10 in the longitudinal grooves 38 when the shaft 16 is inserted into the bore 14 up to the shoulder 22 , so that the drill attachment is secured both in the longitudinal direction and in the circumferential direction.

The spring ring 30 surrounds a clamping sleeve 50 mounted on the shaft 5 so as to be longitudinally displaceable, which can be pushed over the entire length of the spring tongues, or at least over its free end, and the inside diameter of which is dimensioned such that deflection of the locking heads 34 does not radially outward is possible if the sleeve 50 is pushed over it. It can also be provided that the corresponding spring tongue 32 is loaded radially inwards by sliding the sleeve 50 over a locking head 34. The clamping sleeve 50 is detachably connected to a threaded ring 54 via a screw thread 52. The threaded ring 54 is displaceable on the shaft 5, a shoulder 58 serving as a stop at the transition to the sleeve 10. On the side opposite the shoulder 58, the threaded ring 54 is loaded by a spring ring 60, which in turn is supported on a retaining ring 62 pressed onto the shaft 5. The spring ring 60 presses the threaded ring 54 against the shoulder 58 in the absence of external forces, so that the entire spring ring 30 including the locking heads 34 is enclosed by the clamping sleeve 50 in this rest position. Advantageously, the sleeve 50 is dimensioned such that in the rest position, as shown in FIG. 1, it also covers the space between the threaded ring 54 and the retaining ring 62, in which the spring ring 60 is located, so that this area is closed to the outside and in front is protected from the ingress of dirt. The sleeve 50 has an annular flange 51 which serves for better handling when the sleeve is withdrawn. - 11 -

To couple a drill bit 3 to the holding part 1, the clamping sleeve 50 is withdrawn by means of the ring flange 51, so that the spring tongues 32 and the locking heads 34 are released so far that they can move radially outwards. Then the shaft 16 is inserted into the bore 14 until the shoulder 22 abuts the edge 20 of the sleeve 10 and the locking heads 34 of the spring tongues 32 snap into the annular groove 40. The drill is then rotated against the holding part until the spring tongues 32 engage in the longitudinal grooves 38 of the drill attachment 3. Subsequently, the clamping sleeve 50 is released, which is then pressed by the spring ring 60 and the threaded ring 54 towards the drilling attachment 3 until the threaded ring 54 strikes the shoulder 58 and the clamping sleeve 50 includes the locking heads 34 so that they no longer radially can be moved outside and the spring tongues 32 are held securely in the grooves 38 and the locking heads 34 in the groove 40. To release the drilling attachment 3 from the holding part 1, the clamping sleeve 50 is withdrawn again, so that the locking head 34 can move radially outwards and the drill 3 can be removed. The groove 40 is advantageously designed in such a way that, on the one hand, the latching head is held securely in the groove, but the drilling tool 3 can be removed by hand for replacement when the clamping sleeve 50 is withdrawn.

In the course of a drilling process, body fluids and small bone particles can get into the spaces between the holding part 1 and impair the mobility of the individual components. It is therefore provided that the holding part can be disassembled for cleaning. For this purpose, the threaded ring 54 has bores 70 which can be made to coincide with bores 72 at the bottom of the bore 14. Holding mandrels 74 of a holding tool 76 can now be inserted through the bores 70 and 72 in order to fix the threaded ring 54 with respect to the holding tool 76. As a rule, a plurality of holding mandrels 74 are provided in the holding tool 76, in - 12 -

7, however, only one such mandrel is shown for the sake of simplicity. When the threaded ring 54 is fixed by the mandrels 74 of the holding tool 76, the clamping sleeve 50 can be unscrewed from the threaded ring and pulled off in the direction of the coupling 7. In order to facilitate the turning off of the clamping sleeve 50, the ring flange 51 is provided with depressions 78. Alternatively, it can also be specially designed for attaching a turning tool, for example in a polygonal shape. When the clamping sleeve 50 is removed, the space between the threaded ring 54 and the clamping ring 62 is easily accessible and can therefore be easily cleaned.

Various modifications and modifications to the above-described embodiment are possible. In particular, the drill 3 and the holding part 1 can be designed to be complementary to the illustrated embodiment, i.e. the drill has a receiving sleeve with a bore into which a shaft of the holding part is inserted for axial centering. From the point of view of being able to reuse as many parts of the system as possible, the clamping sleeve and possibly also the spring tongues will expediently continue to be arranged on the holding part. In principle, however, it is also possible to also provide the spring tongues and / or the clamping sleeve on the drill attachment. In particular, it is possible to provide the clamping sleeve on the holding part and the spring elements on the drill attachment, the spring elements then being completely released when the clamping sleeve is withdrawn.

The holding part 1 does not necessarily have to have a coupling 7 for a drilling device or, more generally speaking, be detachably connected to a drilling device. Rather, the holding part can also be firmly connected to the drilling device or form part of the same.

The in the preceding description, the drawings and Features of the invention disclosed in the claims can be essential both individually and in any combination for realizing the invention in its various embodiments.

Claims

- 14 -IMZ manufacturing and sales company for dental technology mbHTalstraße 2370794 Filderstadt patent claims

1. Drill for producing a hole in a bone tissue with a holding part (1) and a drill attachment (3) which can be detachably connected to the holding part (1) via a coupling device, characterized in that the coupling device (10, 14, 16 , 32, 38, 40) a shaft (16) on one (3) of the two parts (1, 3 ^" ) and a sleeve (10) with a bore (14) complementary to the shaft (16) on the other (1 ) of the two parts (1, 3) into which the shaft (16) can be inserted, and furthermore has a securing device (32, 34, 38, 40) for preventing a relative movement between the holding part (1) and the drilling attachment (3) , such that the shaft (16) in the engaged state 1 5 -

Bore (14) engages and the drill attachment (3) is secured to the holding part (1); and that the holding part (1) and the drill attachment (3) each have a coolant bore (18, 24) for the passage of a coolant, the coolant bore (18) of one part (1) having an opening in the bore (14) of the sleeve ( 10) and the coolant bore (24) of the other part (3) has an opening in the region of that portion of the shaft (16) which is received in the sleeve (10) in the coupled state, such that a coolant connection for supplying in the coupled state of coolant from the holding part (1) to the drill attachment (3) is formed.

2. Drill according to claim 1, characterized in that at least one locking element (32, 34) on one (1) of the two parts (1, 3) and an associated recess (38, 40) on the other (3) of the two parts (1, 3) for the positive connection of

Holding part (1) and drilling attachment (3) are provided, the latching element (32, 34) the part (1) having the sleeve with a location (38, 40) of the part having the shaft (16)

(3) connects, which lies outside the bore (14) of the sleeve (10) when the shaft (16) is inserted into the bore (14) and the locking element (32, 34) in the associated recess

(38, 40) are engaged.

3. Drill according to claim 1 or 2, characterized in that at least one spring tongue (32) with a locking head (40) on one (1) of the two parts (1, 3) is provided and the other part (3) has a groove ( 38) for receiving at least a part of the free end of the spring tongue and is provided with a recess (40) for receiving the locking head, which is arranged so that the locking head (34) can engage in the recess (40) when the shaft (16) is inserted into the bore (14) and the spring tongue (32), at the end of which the locking head (34) is located, is at least partially received in the groove (38). - 1 6 -

4. Drill according to claim 3, characterized in that the recess for receiving the locking head is designed as a substantially in the circumferential direction of the holding part (1) or the drill attachment (3) extending groove (40).

5. Drill according to one of claims 2 to 4, characterized by a sliding sleeve (50) which is arranged on the holding part (1) or the drill attachment (3) so that it via the locking element or the locking elements (32) in a securing position can be pushed in such a way that the locking element (s) (32) is / are held in the recess (s) (38, 40) by the sliding sleeve (50) when it is in the securing position.

6. Drill according to claim 5, characterized in that the sliding sleeve (50) is biased by a spring element (60) in the securing position.

7. Drill according to claim 5 or 6, characterized in that the sliding sleeve (50) is detachably mounted.

8. Drill according to claim 7, characterized in that the sliding sleeve (50) is screwed to a threaded ring (54) which is mounted so as to be displaceable in the longitudinal direction relative to the holding part (1) or the drill attachment (3) and a device (70, 72) for preventing a rotational movement relative to the holding part (1) or the drilling attachment (3).

9. Drill according to claim 7 or 8, characterized in that the securing device has a spring ring (30) with a plurality of elastic spring tongues (32) which is at least partially surrounded by the sliding sleeve (5u) in the securing position.

10. Drill attachment for making a hole in bone tissue, characterized in that it has a coupling device - 1 7 -

(16, 38, 40) for connecting to a holding part (1) and thereby for producing a drill according to one of claims 1 to 9.

11. Holding part for receiving a drill bit for making a hole in bone tissue at one end and for connecting to a drill at its other end, characterized by a coupling device (10, 14, 32, 34) for connecting to a drill bit (3) for generation of a drill according to one of claims 1 to 9.

12. Holding part according to claim 11, characterized in that it has a coupling device (7) for releasably connecting to a drilling device at the end which is opposite the coupling device for connecting to the drill attachment (10, 14, 32, 34).

13. Drilling device for making holes in bone tissue, characterized in that it has a holding part according to claim 11 as a firmly connected component.