Osteotomy drill for drilling holes in bone for receiving implants or other fixing devices, in particular implants or screws in the dental field

Abstract

The invention relates to an osteotomy drill made of a material harder than bone, comprising a rod (1) terminating in a tip (2), and, projecting laterally from the rod (1), a helical band (4) extending helically around the rod (1), the free edge (7) of the helical band (4) being designed as a sharp or cutting edge.

Description

Osteotomy drill for drilling holes in bone to receive implants or other fixing devices, including implants or screws in dentistry.

[0001] The present invention relates to an osteotomy drill for drilling holes in bone or the like, the holes being intended to receive an implant or other fixation device, in particular an anchoring base such as a screw to which a prosthesis, particularly a dental prosthesis, is subsequently attached. The present invention is of particular interest for performing an osteotomy of the cortical bone beneath the sinus membrane.

[0002] From US2023 / 0013222A1, a conical drill or osteotome intended for osteotomy in dentistry is known. This anterior art drill has a longitudinal shank defining a longitudinal axis of rotation of the drill and terminates distally in a grooved, conical body, the grooved conical body having a distal tip and longitudinal grooves cut into its lateral surface, the grooves extending helically.

[0003] From US2003 / 018337A1, a drilling and tapping tool for forming a threaded opening in bone is further known. The tool comprises a shank, followed by a tapping portion terminating in a drill portion. The tapping portion has a helical band projecting laterally from the shank, the helical band terminating where the drill begins. The helical band has a distal face facing the drill and a proximal face facing away from the drill, both faces being concave with their concavity facing away from the drill. In one embodiment, the drill portion has the form of a cylindrical shank with longitudinal grooves extending helically on its lateral surface.

[0004] This type of conical drill bit allows for the creation of so-called "densified" holes, meaning holes whose lateral walls have been reinforced or densified by compacting the bone chips against them. This process requires two steps. The first step involves drilling an initial hole using a different type of drill bit to create a precursor hole. Then, the conical drill bit is inserted into this precursor hole and rotated in one direction to complete the drilling, and then in a second direction. opposite direction, to the first direction, to achieve densification, the rotation in the second direction having the effect of compressing the internal lateral bone wall of the precursor hole and, thus, compacting and densifying it.

[0005] These drills of the earlier art are thus complicated to use which requires, in order to obtain the final hole, having several different types of drills available and a three-step procedure: a first step to make the hole, a second step to perfect the drilling, and then a third step to densify it.

[0006] The present invention aims to provide an osteotomy drill that allows the final densified hole to be obtained using a single drill and in a single step.

[0007] According to the invention, an osteotomy drill, made of a material harder than bone, for example ceramic, zirconia, stainless steel, titanium or other similar alloy, comprises a shank ending in a pointed part, characterized by a helical band projecting laterally from the shank and extending helix-style around the shank, the free edge of the helical band being made sharp or cutting.

[0008] Preferably, the width of the helical band, measured radially along the band between the free edge and the stem, varies, notably increasing along the helix as one moves away from the tip.

[0009] Preferably, the helical band extends helvenly over at least 900°, especially over 990° or more.

[0010] Preferably, the helical band is inclined towards the tip, in particular with a slope, relative to the perpendicular to the stem, of between 5° and 80°, in particular about 45°.

[0011] Preferably, the stem, especially cylindrical, especially circular, extends beyond the helical band, up to the pointed part.

[0012] According to a preferred embodiment, the helical strip extends continuously.

[0013] Preferably, the helical band has a distal face turned towards the tip and a proximal face turned away from the tip, both faces being concave with their concavity turned towards the tip.

[0014] Preferably, the distance, measured along the axis of the stem, between the most distal point of the free edge and the tip is between 0.3mm and 0.9mm, in particular between 0.5mm and 0.7mm.

[0015] By using the drill according to the invention, a surgeon can perform the creation of the hole and its densification in a single step, that is, during the very creation of the hole. The more proximal threads trap the bone chips formed by the more distal threads and the tip and compact them against the walls of the hole, particularly under the sinus membrane in the case of a subsinus osteotomy.

[0016] The present invention also relates to a method for drilling a hole in a bone, in particular the cortical bone under the sinus membrane, the method comprising the step of taking the drill bit according to the invention, coupling it to a motor and pressing the tip against the cortical bone to drill it until the final hole is drilled.

[0017] The present invention also relates to an osteotomy kit comprising a plurality of drills according to the invention, for example three drills, each drill having a different size, for example three sizes of respectively 3.5mm, 4mm and 4.5mm and a motor to rotate the drills.

[0018] Figure 1 shows a schematic perspective view of an embodiment of a drill according to the invention.

[0019] In Figure 1, the osteotomy drill shown has a cylindrical shaft 1, notably with a circular cross-section, terminating distally in a pointed portion 2. Proximally, the shaft has an interface 3 for engaging the drilling motor. The exact configuration of this interface 4 may vary depending on the type of motor used, and may even, in some cases, consist of only a simple smooth portion of the shaft against which the jaws of a collar attached to the motor clamp.

[0020] The pointed part 2 is shown as conical in shape. It could have any other shape, as long as its piercing function is achieved. In particular, to improve this drilling function, the point can be made of diamond and / or sandblasted to make its attack surface rough.

[0021] A helical band 4 extends laterally from the stem 1. The helical band 4 extends helix around the cylindrical stem 1. The band 4 extends from a distal straight edge 7d to a proximal straight edge 7p, between a free cutting edge 7 that extends helix around the stem 1 and a base edge 8 that extends helix along the outer surface of the stem 1.

[0022] The helical band 4 comprises approximately three turns, respectively distal 4d, intermediate 4i, and proximal 4p. The distal turn 4d extends from 0° to 360°. The intermediate turn 4i extends from 361° to 720°, and the proximal turn 4p extends over less than 360°, specifically from 721° to 990°. The straight edge 7p, of which only the corner it forms with the free cutting edge is visible in the figure, is offset, viewed from above, by an angle of approximately 90° with the distal edge 7d.

[0023] The width extension, i.e. the distance measured radially along the band 4 between the stem 1 and the free cutting edge 7, increases from the distal edge 7d to the proximal edge 7p.

[0024] The helical band 4 has a distal surface 5 facing towards the tip 2 and a proximal surface 6 facing in the opposite direction, towards the interface 3.

[0025] Starting from the distal edge 7d, and moving along the band in a counterclockwise direction (positive direction) as seen from interface 3 (i.e., as seen by the surgeon when using the drill), the helical band 4 comprises a first region 6.1 of substantially constant width h corresponding to the width of edge 7d, this first region extending over a distance of 180° along the helical band. It is followed by a first transition region 6.2 extending from 180° to 360°, in which the width of the band changes from the width h of edge 7d to the width L of the intermediate spiral measured at 360°, thus corresponding to edge 7d, as seen from above in Figure 1. The first transition region is followed by a second region 6.3 of constant width extending from 360° to 540° with a width I2. The second region 6.3 is followed by a second region 6.4 transition which extends from 540° to 720°, in which the width of the band changes from width I2 to a wider width. The small end of the proximal 4p spiral corresponds to the edge 7d, as seen from above in Figure 1. The second transition region 6.4 is followed by a third region 6.5 of constant width extending from 720° to 900°. The third region 6.5 is followed by a third transition region 6.6 extending from 900° to 990°, terminating at the proximal edge 7p.

[0026] The first width h is less than the second width L and the second width I2 is less than the third width I3.

[0027] Thus, the width of the band decreases in steps. Another possible embodiment would be to progressively decrease the width of the helical band from the distal edge to the proximal edge.

[0028] Over its entire length, the helical band 4 is inclined relative to the axis of the rod 1 at an angle greater than 90°, and thus extends in slope from the rod 1 towards the tip 2. This radial inclination angle of the band can for example be between 5° and 80°, in particular between 30° and 60°, in particular equal to about 45°.

[0029] In the embodiment shown in Figure 1, this angle is essentially constant along the entire length of the helix. However, it could be varied along this length, particularly depending on the specific turn.

[0030] In the embodiment shown in Figure 1, the helical band 4 is continuous from the distal edge 7d to the proximal edge 7p. However, it could also, according to the invention, be made in a discontinuous form, for example by providing, at regular or irregular intervals, empty regions, for example in the form of radial notches or slots.

[0031] The drill bit shown has approximately 3 turns. It would obviously be possible to have more, such as 4 or 5.

[0032] Several drill sizes are available depending on the size of the implant to be implanted.

[0033] The drill bit size is defined as its greatest lateral extension, perpendicular to the shank 1, that is, the greatest lateral extension of its proximal spiral. This size corresponds to the measured distance perpendicular to the rod 1 from point 7(720°) corresponding to the abscissa 720° of extension along the helix from edge 7 to point 7(900°) diametrically opposite.

[0034] Generally, for a 4mm diameter implant, a 3.5mm drill bit is recommended (shown in Figure 1). For a 4.5mm implant, a 4mm drill bit is recommended, and for a 5mm implant, a 4.5mm drill bit is recommended.

[0035] The pitch of the helix, that is to say the distance measured along the axis of the rod 1 between two points separated by 360°, for example between 7(0°) and 7(360°) can be between 0.6mm and 1.5mm, in particular between 0.7mm and 1mm.

[0036] The diameter of rod 1 can be between 0.75mm and 1.5mm, in particular between 0.8mm and 1.2mm, in particular be equal to about 1mm.

[0037] The distance, measured along the axis of the stem 1, between the most distal point 7(0°) of the free edge 7 and the tip 2 can be between 0.3mm and 0.9mm, in particular between 0.5mm and 0.7mm.

[0038] In the case of a 3.5mm drill bit, the largest width dimension of the intermediate thread can be 3mm and the largest width dimension of the distal thread can be 2.5mm.

[0039] In the case of a 4mm drill bit, the largest width dimension of the intermediate thread can be 3.5mm and the largest width dimension of the distal thread can be 3mm.

[0040] In the case of a 4.5mm drill bit, the largest width dimension of the intermediate thread can be 4mm and the largest width dimension of the distal thread can be 3.5mm.

[0041] The drill bit can be made of zirconia, ceramic, stainless steel, titanium, or any other material commonly used for this type of drill bit. It can also be made of high-density polymer.

[0042] The drill bit can be in one piece or in several pieces fixed together.

[0043] The drill bit can be manufactured, for example, by machining, molding, 3D printing, or any other well-known process.

Claims

Demands

1. Osteotomy drill made of a material harder than bone comprising a shank (1) terminated by a pointed portion (2), characterized by a helical band (4) projecting laterally from the shank (1) and extending helix around the shank (1), the free edge (7) of the helical band (4) being made sharp or cutting.

2. Drill according to claim 1, characterized in that the width of the helical band (4), measured radially along the band between the free edge (7) and the shank (1) increases along the helix as one moves away from the tip (2).

3. Drill according to claim 1 or 2, characterized in that the helical band (4) extends helix over at least 900°, in particular over 990° or more.

4. Drill according to any one of claims 1 to 3, characterized in that the helical band (4) is inclined towards the tip (2).

5. Drill according to claim 4, characterized in that the band (4) is inclined towards the tip of a slope, with respect to the perpendicular to the shank (1), between 5° and 80°.

6. Drill according to claim 5, characterized in that the slope is approximately 45°.

7. Drill according to any one of the preceding claims, characterized in that the helical band extends continuously.

8. Drill according to any one of the preceding claims, characterized in that the helix pitch, i.e. the distance measured along the axis of the shank (1) between two points separated by 360°, for example between 7(0°) and 7(360°), is between 0.6mm and 1.5mm, in particular between 0.7mm and 1mm.

9. Drill according to any one of the preceding claims, characterized in that the helical band has a distal face turned towards the tip and a proximal face turned away from the tip, both faces being concave with their concavity turned towards the tip.

10. Drill bit according to any one of the preceding claims, characterized in that the drill bit is made of zirconia or ceramic.

11. Drill bit according to any one of the preceding claims, characterized in that the drill bit has 3 to 5 turns.

12. Drill bit according to any one of the preceding claims, characterized in that the distance, measured along the axis of the shank, between the most distal point of the free edge and the tip is between 0.3 mm and 0.9mm, especially between 0.5mm and 0.7mm.

13. A drill according to any one of the preceding claims, characterized in that the shank, in particular cylindrical, in particular circular, extends beyond the helical band to the pointed portion.

14. An osteotomy kit comprising a plurality of drills according to any one of the preceding claims, for example, three drills, each drill having a different size, for example, three sizes of 3.5 mm, 4 mm, and 4.5 mm respectively, and a motor for rotating each drill.

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