Drill bit and method for osteotomy using same

Abstract

The present disclosure provides a drill bit including a root tip portion, a coronal end portion, and a longitudinal axis extending between the root tip portion and the coronal end portion. The drill bit further includes: a bit core extending along the longitudinal axis; at least two grooves, each groove defined by a concave surface forming a recess along the drill core; and a root tip end face, the root tip end face being at the root tip end. A root tip edge of the concave surface and a root tip edge of the drill core define a shape of the root tip face such that the root tip face defines contours of retention arms at the root tip, each retention arm being formed between the concave surfaces of adjacent grooves. The present disclosure also provides a method of creating an osteotomy using a drill bit.

Description

Technical Field

[0001] This disclosure relates to a drill bit for preparing an implantation site for a dental implant. This disclosure also relates to performing an osteotomy to prepare the implantation site. Background Technology

[0002] Before inserting a dental implant, a recess needs to be prepared in the patient's maxilla or mandible. This osteotomy is a crucial step in providing the dental implant and has a significant impact on osseointegration and its long-term success.

[0003] Given that bone density, orientation, and quality vary from patient to patient, a variety of tools are typically required to prepare a suitable implant receiving recess. However, the more interdependent the tools used to create the recess, the more extensive the treatment options become. This makes deciding on the details of such a protocol quite complex and time-consuming. Furthermore, aligning these different tools used to prepare the implantation site can become quite difficult.

[0004] It must be considered that the jawbone has a relatively hard outer layer (i.e., cortical bone) beneath a weaker, spongy bone structure (i.e., cancellous bone). Cortical bone, which provides the hard cortex, is much denser and less elastic than cancellous bone. When preparing the bone recess for receiving a dental implant, the drill must create this recess, extending from the cortical bone into the cancellous bone. Therefore, the drill should be able to work through different types of bone tissue within the patient during osteotomy.

[0005] During the development of osteotomy techniques, the drill was guided by dental professionals. Therefore, dental professionals also have an influence on the performance of osteotomy.

[0006] In light of the above, efforts have been made to improve the process of creating recesses within bone tissue in preparation for dental implant insertion. In this regard, WO 2017 / 129828 A1 discloses a drill bit for preparing bone recesses, which is configured to simultaneously densify and cut bone tissue. Summary of the Invention

[0007] The usual goal is to provide a drill bit that facilitates osteotomy independently of the patient's jawbone and between different jawbones or between patients, so that the bone recess for receiving the dental implant appears as desired, i.e., the bone recess is neither under-prepared nor over-prepared.

[0008] Providing dental professionals with feedback on the progress of preparing for implantation of the recess is also a goal.

[0009] With regard to these purposes, a drill and method for performing osteotomy, as defined in the independent claim, are provided. The dependent claims specify preferred features of the claimed invention.

[0010] According to a first aspect of the present disclosure, a drill bit is provided, comprising a root tip, a coronal end, and a longitudinal axis extending between the root tip and the coronal end. Furthermore, the drill bit includes: a drill core extending along the longitudinal axis; at least two grooves, each groove defined by a concave surface forming a recess along the drill core; and a root tip face at the root tip. The root tip edge of the concave surface and the root tip edge of the drill core define the shape of the root tip face such that the root tip face defines a profile of a retaining arm at the root tip, wherein each retaining arm is formed between the concave surfaces of adjacent grooves. At least one of the at least two grooves extends along the longitudinal axis from the root tip, extending over at least 70% of the length of the drill bit configured to interact with bone tissue, preferably over the entire length of the drill bit configured to interact with bone tissue.

[0011] Along the longitudinal axis, the linear distance between the root tip of the at least one groove and the coronal point of the groove is at least 50% of the total linear distance of the drill bit.

[0012] Preferably, the at least one groove extends along the longitudinal axis L over the entire length of the drill bit (operating portion). In other words, a first end of the at least one groove is located at the root tip of the drill bit, and a second end of the groove is located at the crown end of the drill bit. The at least one groove may extend continuously between the first end and the second end. The drill bit may include two or more grooves having the same features described above.

[0013] Having at least one cutting groove extending along a significant portion of the drill bit allows for the cutting of bone tissue along the entire groove. The shape / volume of the osteotomy created by the cutting groove can substantially correspond to the shape / volume of the implant core. When the implant is subsequently placed in the prepared osteotomy, only the implant threads (or threads) (not the implant core) compress the bone tissue. This results in maximum preservation of bone tissue. In other words, when the implant is placed in the osteotomy, only the implant threads radially push the bone relative to the implant axis. Therefore, most of the bone tissue is spared from destructive overcompression, and ultimately this leads to better osseointegration. This is especially important for dense bone tissue, as overcompression can damage dense bone tissue and even cause fractures of a portion of the patient's jawbone. The drill bit according to the invention is particularly suitable for preparing osteotomies in this type of hard bone.

[0014] The above advantages are further enhanced in embodiments of the invention, wherein at least one cutting groove extends along the entire length of the drill bit.

[0015] Each groove extends from the root tip face toward the coronal end. In a cross-section perpendicular to the longitudinal axis, the concave surface of the groove forms a recess along the profile of the drill bit core. At the root tip face, each groove creates a recess in the profile of the end face.

[0016] Between adjacent recesses, the profile of the end face is arm-shaped and represents the profile of the retaining arms. This profile preferably has a longitudinal extension in the radial direction (relative to the longitudinal axis) and extends from the central region of the root tip face to the outer edge of the root tip face (typically defined by the root tip edge of the drill core). The number of retaining arms equals the number of recesses. Preferably, the drill bit includes three recesses.

[0017] The end face provides bluntness to the drill tip, which at least reduces the drill's forward cutting capability. In other words, the end face increases the force and torque required to further advance the drill when the apical face contacts the bone tissue.

[0018] Furthermore, the drill bit core preferably tapers gradually along at least a portion of the drill bit in the apical direction. This tapered portion serves to increase the diameter of the pores in the bone tissue as the drill bit advances. Additionally, cutting grooves extending along this tapered portion of the drill bit cut bone tissue at each point on their cutting edge and create osteotomies or pores. The shape of the drill bit expands the osteotomy at each point and prepares the size for the dental implant.

[0019] When the apical facet contacts the bottom of the guide hole in the bone tissue at the implantation site, the retaining arm is configured to interact with the bone tissue, thereby generating a retaining force that counteracts the driving torque applied to the drill bit. In other words, the retaining arm, upon contact (specifically, surface contact), generates a frictional force with the bone tissue at the bottom of the guide hole, which resists the driving torque applied to the drill bit.

[0020] Therefore, the retaining arm at the root tip of the drill bit provides feedback, indicating to the user that the end of the previously prepared hole (i.e., the guide hole) within the bone tissue has been reached, and thus serves to prevent under- or over-preparation of the osteotomy.

[0021] The drill bit may also include at least one pilot thread projecting from the drill core. The pilot thread extends helically along the drill core and preferably tapers gradually towards the root tip. Specifically, the pilot thread is a single thread.

[0022] The drill bit's guide thread allows for enhanced control over its advance into the bone tissue, as it converts the drill bit's rotation into a predetermined feed rate. More specifically, each rotation causes the drill bit to advance a distance corresponding to the pitch of the guide thread. In this way, the guide thread is particularly helpful in inserting the drill bit into a previously prepared pilot hole at the implantation site.

[0023] The pilot thread can taper gradually in the root direction of the drill bit. That is, the outer diameter of the pilot thread decreases in the coronal-root direction. Preferably, the thread height of the pilot thread is substantially constant in the longitudinal axis direction. It may also, or alternatively, decrease in height in this direction. Preferably, the pilot thread does not extend to the root tip of the drill bit or the portion where the retaining arm is arranged.

[0024] The guide thread is preferably configured such that the forward driving force generated by converting torque into the drill bit advancing into the previously prepared hole is insufficient to advance the drill bit into unprepared bone tissue. Instead, when a certain torque limit is reached, the guide thread loses grip and begins to rotate freely without drilling deeper into the tissue.

[0025] Therefore, the pilot thread can enhance the aforementioned effect of providing feedback upon reaching the end of a previously drilled hole or pilot hole by increasing the torque until the thread loses grip and spins freely. Thus, the root tip face, retaining arm, and pilot thread interact with each other to provide the counteracting feedback torque.

[0026] The radial height of the guide thread is particularly less than the radial extension of the retaining arm profile at the root tip face.

[0027] As described above, the profile of the retaining arm at the root tip face extends from the central region of the root tip face to the outer edge. The length of the profile from the central region to the outer edge is preferably greater than the radial height of the guide thread. Typically, the longer retaining arm increases the counteracting torque as the drill bit reaches the bottom of the previously drilled hole.

[0028] Each retaining arm may have a radial extension greater than its circumferential width at the tip formed by the root tip edge of the drill core.

[0029] The guide thread may have a non-circular outer circumferential profile, preferably a triangular elliptical profile.

[0030] The advantage of a non-circular, specifically triangular-elliptical, profile is that it makes it easier to form thread grooves as a pilot thread compared to conventional threads. It also works by gradually densifying the bone structure along the thread path of the pilot thread. In this way, the bone structure can be preserved rather than cut away, which reduces the influence of the pilot thread on the shape of the hole formed by the drill bit.

[0031] Furthermore, the drill core may have a non-circular profile in a cross-section perpendicular to the longitudinal axis, wherein the non-circular profile preferably rotates about the longitudinal axis in the longitudinal direction of the drill bit, thereby producing a twisted non-circular drill core.

[0032] The non-circular profile of the drill core utilizes the elasticity of bone tissue to create a recess in the bone tissue as the drill rotates and is inserted. Unwilling to be bound by theory, the non-circular profile helps create a recess that allows the drill to maintain its insertion direction. Due to its compacting effect on bone tissue, it also has a positive effect on the primary stability of dental implants inserted into this recess. The non-circular profile of the drill core also provides an anterior clearance angle that facilitates cutting through bone tissue.

[0033] A twisted, non-circular drill bit core has the advantage of distributing the forces generated by the non-circular profile as the drill bit is inserted into bone tissue along its circumference. This in particular prevents the drill bit from deviating when entering the pilot hole.

[0034] The non-circular profile of the drill bit core and the non-circular profile of the guide thread can create a circumferential offset. This configuration also enhances the force distribution along the circumference of the drill bit and prevents the drill bit from becoming misaligned or offset relative to its desired insertion trajectory.

[0035] Preferably, the root tip edge or circumferential edge of the root tip surface is arranged in a plane perpendicular to the longitudinal axis.

[0036] This structural feature results in the retaining arm contacting the bottom of the previously drilled hole substantially simultaneously. Therefore, the resistance torque increases more rapidly and provides clearer feedback. In this respect, at least the apical surface of the retaining arm, and preferably the apical facet, is flat to induce surface contact with the bone tissue at the bottom of the guide hole.

[0037] The concave surface of each groove and the circumferential surface of the drill bit core preferably form a cutting edge. If a guide thread is provided, the cutting edge may even more preferably include the profile of the guide thread.

[0038] Therefore, this groove not only forms a retaining arm at the root tip face but can also be a cutting groove, which helps to prepare a recess in the bone tissue that substantially corresponds to the rotational shape of the drill core. The cutting edge helps to form the bone recess and further enables the retaining arm and guide thread (if present) to cause a more detectable increase in torque that resists further rotation of the drill bit upon contact with the bottom of the previously drilled hole.

[0039] The concave surface and the root tip face can form at least partially a cutting edge at the root tip edge of each concave surface, the cutting edge having a forward tilt angle and essentially no forward clearance angle.

[0040] Since there is essentially no front clearance angle at the edge formed at the root tip face of the drill bit, the forward cutting capability of the root tip face is significantly reduced.

[0041] Furthermore, due to the grooves extending in the longitudinal direction of the drill bit, the tilt angle is relatively large. Therefore, the surface of the retaining arm (the surface facing the predetermined rotation direction of the drill bit) formed at the edge between the concave surface and the root tip face collects or scrapes bone tissue from the bottom of the previously drilled hole. This bone tissue tends to generate friction and torque, counteracting the rotation of the drill bit and thus providing feedback.

[0042] At least two grooves extend specifically helically along the drill core. The angle between the root tip face of the drill and the concave surface of the groove (formed by the helical extension of the groove) supports the functionality of the retaining arm by collecting or scraping away bone tissue at the root tip edge, where the root tip face and the concave surface engage. Furthermore, the helical path of the groove provides a more uniform load distribution along the circumference of the drill. This is particularly advantageous when drilling at slow speeds and thus results in controlled preparation of the bone recess or implant recess. In this respect, three grooves are preferred.

[0043] Furthermore, this disclosure provides a method for creating an osteotomy using a drill bit, specifically a drill bit as described above. The method includes the steps of drilling a hole with a guide drill and increasing the size of the hole for inserting a dental implant using the drill bit. The drill bit includes: a drill core; at least two grooves, each groove being defined by a concave surface forming a longitudinal recess along the drill core; a root tip face at the root tip of the drill bit; and a retaining arm extending coronally from the root tip face. Each retaining arm is formed between the concave surfaces of adjacent grooves. When the root tip face contacts the bottom of the hole drilled with the guide drill, the retaining arm generates a braking force that can be used to stop the rotation of the drill bit.

[0044] Upon contact with the bottom of the hole, the root tip face acts as a stop. Additionally, the rotating retaining arm collects bone tissue or debris at the bottom, generating a torque that counteracts the drill's driving torque. This provides feedback to the dental professional using the drill or to sensors or mechanisms such as torque limiters as a signal to stop the drilling process.

[0045] Preferably, the tip of the guide drill has a diameter larger than the diameter of the root tip facet. This has the advantage that the root tip facet does not contact the bone tissue at the beginning of preparing the bone recess with the drill bit until the drill bit reaches the end of the guide hole. Otherwise, the root tip facet of the drill bit would impede the drilling process because its forward drilling capability would be at least significantly reduced. Furthermore, the torque signal more clearly indicates the end of the preparation.

[0046] The diameter at the tip of a directional drill refers to the diameter at the boundary between the front cutting edge formed by the sharp angle of the directional drill (if present) and the circumferential surface extending in the direction along the longitudinal axis of the directional drill. Attached Figure Description

[0047] The following figures illustrate preferred embodiments according to the features of this disclosure. These embodiments should not be construed as limiting, but are only used to enhance the understanding of this disclosure.

[0048] Figure 1 This is a partial side view of the drill bit according to this disclosure;

[0049] Figure 2 yes Figure 1 The image depicts a partial view of the drill bit, illustrating the root tip of the drill bit in perspective.

[0050] Figure 3 This is a front view of the tip of the drill bit;

[0051] Figure 4 This is a cross-sectional view of the drill bit according to this disclosure;

[0052] Figure 5 This is another cross-sectional view of the drill bit according to this disclosure; and

[0053] Figure 6 This is yet another cross-sectional view of the drill bit according to this disclosure. Detailed Implementation

[0054] In the following description, exemplary embodiments of a tool for preparing recesses in bone tissue will be described with reference to the accompanying drawings, specifically embodiments of drill 1 according to this disclosure.

[0055] Figure 1 An exemplary embodiment of a drill bit 1 according to this disclosure is shown. The drill bit 1 has a root tip portion 2 and a crown end portion (not shown). It extends along a longitudinal axis L, which also serves as the axis of rotation. The crown end portion is preferably configured to be coupled to a dental drill (not shown) to transmit drive torque to the drill bit 1.

[0056] The drill bit 1 includes a drill core 20 having a circumferential surface 21. The drill core 20 preferably tapers gradually in the coronal-root direction (i.e., toward the root tip 2). The drill bit 1 includes at least two grooves 40. Each groove 40 is defined by a concave surface 41. The concave surface 41 forms a longitudinal recess (i.e., groove 40) that begins at the root tip 2 and extends along the drill core 20. Thus, each groove 40 has a concave profile defined by the concave shape of the concave surface 41.

[0057] The drill core 20 preferably has a substantially continuous profile along the longitudinal axis L of the drill bit 1. The profile of the drill core 20 is "substantially" continuous due to the groove 40 and the guide thread 30 (if present). In other words, the profile does not include discontinuities, such as discontinuities arranged substantially perpendicular to the longitudinal axis L, such as steps in the diameter of the drill core 20.

[0058] At the root tip portion 2, the drill bit 1 includes a root tip face 10. The root tip face 10 is preferably oriented substantially perpendicular to the longitudinal axis L of the drill bit 1. Figure 2 As shown, the profile of the root tip face 10 is defined by the root tip edge 42 and root tip edge 22 of the concave surface 41. At the root tip edge 22 of the drill bit 20, the drill bit 22 may include a chamfered or rounded edge 23. The chamfer 23 does not form part of the root tip face 10.

[0059] The root tip edge 42 of the concave surface 41 and the root tip edge 22 of the drill core 20 are shaped to conform to the contour of the root tip face 10, and this shape includes an arm-shaped radial extension 12 (in Figure 2 In an exemplary embodiment, the root tip face 10 has three arms. Each of these arm-shaped radial extensions 12 has a tip edge 14a defined by the root tip edge 22 of the drill core 20 and two side edges 14b and 14c defined by the root tip edges 42 of the concave surfaces 41 of two adjacent grooves 40. Specifically, the opposite side edges 14b and 14c of each arm 12 may be defined by substantially half the length of the root tip edge 42 of the groove 40. Preferably, each arm-shaped extension 12 is substantially symmetrical with respect to a radial axis of symmetry extending from the longitudinal axis L.

[0060] The arm-shaped extension 12 extends from the central region 11 of the root tip face 10. Preferably, the central region 11 is formed by a virtual circle (in... Figure 2 and Figure 3 (shown as a circle with dashed lines) defines the virtual circle, which fits into the root tip edge 42 of the concave surface 41.

[0061] Each extension in the arm-shaped extension 12 defines the contour of the retaining arm 50 for collecting bone debris or for scraping bone tissue upon contact with bone tissue at the bottom of the guide hole. This guide hole is created prior to the use of the drill bit 1 to prepare a bone recess that can be fitted for insertion of dental components such as dental implants.

[0062] Each retaining arm 50 extends from the apical face 10 along a portion of the drill core 20 at the apical portion 2 of the drill 1. As the drill 1 rotates, the rotation-facing side 51 of each retaining arm 50 collects bone debris, which in turn counteracts the driving torque applied to the drill 1 (e.g., via a dental handpiece). Therefore, the apical portion of the drill core 20, including the retaining arms, extends along a distance of the drill suitable for collecting bone tissue at the bottom of the guide hole. Each retaining arm 50 extends longitudinally from the apical face 10 to the corresponding guide thread 30.

[0063] Generally, the longer the radial extension of the retaining arm 15, the higher the torque that counteracts the driving torque of the drive drill bit 1 by scraping or collecting bone tissue.

[0064] If the guide hole is formed as a blind hole (i.e., with a flat bottom), then when the root tip face 10 contacts the bottom of the guide hole and the drill bit 1 rotates, the retaining arm 50 is collecting and accumulating bone debris.

[0065] If the drill bit used for drilling the pilot hole has a tapered tip, the pilot hole tapers gradually at its end. Due to this taper, the drill bit 1 will collect and accumulate bone debris when it contacts the tapered wall at the bottom of the pilot hole. The drill bit 1 will also advance further into the pilot hole, shaping its bottom into a blind hole. This results in the apical facet 10 contacting the bone tissue surface.

[0066] Therefore, regardless of the shape of the bottom of the pilot hole, drill bit 1 will exhibit an increase in torque when it reaches the end of the pilot hole. This increase in torque can be used as a feedback signal to stop the drilling process. For example, this increase in torque can activate a torque limiting device, which automatically stops the rotation of drill bit 1.

[0067] Therefore, this design of drill bit 1 ensures that the recess produced by drill bit 1 is neither under-prepared nor over-prepared.

[0068] Furthermore, when the root tip face 10 of the drill bit contacts the bone tissue surface, the root tip face 10 is essentially designed to have no forward drilling capability; that is, the root tip face 10 of the drill bit 1 essentially does not have a significant ability to cut into the bone tissue surface arranged parallel to the root tip face 10.

[0069] In this respect, the flat surface of the arm essentially results in the root tip face 10 having no front clearance angle (i.e., a clearance angle of 0°) at the root tip edge 42 of each groove 40. Depending on the extension trajectory of the groove 40 along the drill core 20, the root tip 2 of the drill 1 may also lack a front tilt angle (i.e., it has a front tilt angle of 0°) at the root tip edge 42 of each groove 40.

[0070] Preferably, the groove 40 extends spirally around and along the longitudinal axis L along the drill core 20. Here, the root tip edge 42 of the groove 40 may have a non-zero tilt angle. However, this tilt angle is quite small (preferably less than 20°, 15°, 10° or 5°). Therefore, the root tip edge 42 tends to scrape away and collect most of the bone tissue, and thus helps to generate torque that counteracts the driving torque of the drill 1.

[0071] The grooves 40 can also change their pitch in the root-to-coronal direction. Specifically, their pitch can be reduced in this direction, thereby reducing the forward tilt angle at the root tip edge 42.

[0072] The exemplary embodiment shown in the figure includes three grooves. Alternatively, two, four, or five grooves 40 may be provided. At the root tip 2 of the drill 1, these grooves 40 define two, four, or five arms, respectively. It has been found that multiple three-grooved grooves 40 are particularly advantageous for preparing bone recesses with the drill 1.

[0073] The groove 40 preferably forms a cutting edge 43 with the drill core 14. More specifically, the surface side of the groove facing the direction of rotation forms a cutting edge with the circumferential surface 21 of the drill core 20. Therefore, the drill 1 has radial cutting capability when it rotates.

[0074] As described above, at least a portion of the drill bit 20 can taper gradually in the coronal-apical direction. Combined with the groove 40, this provides the drill bit 1 with forward cutting capability. In other words, this configuration of the drill bit 1 cuts through bone tissue as it advances, facilitating the insertion of the drill bit 1.

[0075] However, this forward cutting capability of the drill bit 1, resulting from the interaction between the concave surface 41 and the circumferential surface 21 of the drill bit core 20, does not affect the limited cutting capability of the root tip face 10 at the root tip 2 due to its blunt configuration. Therefore, the cutting capability of the cutting edge 43 at the edges of the circumferential surface 21 and the concave surface 41 is used to provide a bone recess with the desired shape.

[0076] As shown in the accompanying drawings, the drill bit 1 may include a guide thread 30. The guide thread extends radially from the drill core 20 and extends around and along the longitudinal axis L at least a portion of the drill core 20. The guide thread 30 preferably does not extend into or within the portion of the retaining arm 50 including the drill root tip 2.

[0077] A guide thread 30 extends along the drill core 20 and is configured to draw the drill bit 1 into bone tissue at a predetermined rate. This rate depends on the rotation-to-advance ratio set by the pitch of the guide thread 30. Preferably, the pitch of the guide thread 30 is in the range of 0.4 mm to 3 mm, more preferably in the range of 0.8 mm to 1.5 mm, and even more preferably in the range of 1.0 mm to 1.2 mm. The guide thread 30 is preferably configured as a single thread, but it can also be designed as a double or triple thread. The guide thread 30 provides the drill bit 1 with self-drilling capability.

[0078] The guide thread 30 is preferably configured to generate a propulsive force less than the propulsive force required to overcome the resistance of the root tip face 10 when it contacts the bone tissue surface at the bottom of the guide hole.

[0079] In cross-section, the pilot thread 30 has a thread profile with an average thread height from the thread ground to the tip of the pilot thread 30, which is less than the diameter of the root tip face 10 of the drill bit 1 (see [reference]). Figure 2 and Figure 3 The average thread height of the pilot thread is particularly in the range of 1% or 2% to 5%, 10% or 30% of the diameter of the root tip face 10.

[0080] Furthermore, the maximum height of the guide thread 30 may not exceed 50% of the diameter of the root tip face 10.

[0081] The height of the guide thread 30 has the effect that when the root tip face 10 contacts the bottom of the guide hole, the thrust generated by the guide thread 30 is insufficient to overcome the thrust resistance of the drill bit 10 caused by the surface contact between the root tip face 10 and the bottom of the guide hole. Therefore, the torque increases and can be used as a feedback signal for the user, sensors, mechanisms, etc., to stop applying driving torque to the drill bit 10 or to indicate that the bottom of the guide hole has been reached.

[0082] In other words, once the root tip face 10 of drill bit 1 contacts the bone tissue at the bottom of the guide hole, an increase in driving torque is required in order for drill bit 1 to rotate continuously. Specifically, this required increase in torque can be detected and used as a feedback signal.

[0083] For example, the increase in torque can be automatically generated by the motor driving drill bit 1, specifically an electric motor. Preferably, a torque limiter is included in the drive system of drill bit 1, which will respond to this increase by stopping the rotation of drill bit 1. Otherwise, such an increase in drive torque may cause the guide thread 30 to slip or idle. Even in this scenario, the advance of drill bit 1 can be stopped when the bottom of the guide hole contacts the root tip face of drill bit 1.

[0084] As previously described and illustrated in the accompanying drawings, the guide thread 30 may be at least partially formed as a tapered thread that tapers gradually in the crown-root direction (i.e., towards the root tip). The guide thread 30 is preferably tapered along the portion where the drill core 20 is also tapered. Furthermore, the taper of the guide thread 30 preferably corresponds to the taper of the drill core 20. In other words, the taper of the guide thread 30 and the taper of the drill core 20 preferably have the same angle relative to the longitudinal axis L, or extend along a parallel path in the cross-section along the longitudinal axis L.

[0085] Furthermore, the guide thread 30 may have a non-circular profile, specifically a triangular-elliptical profile. This non-circular profile of the guide thread 13 may also be twisted along the longitudinal axis L of the drill bit 1.

[0086] The non-circular profile, specifically in conjunction with the groove 40, has the advantage of creating a threaded path in the bone tissue based on cutting and densification. In other words, the threaded path is generated in part based on the elastic deformation of the bone tissue. Because the threaded path is generated based on the elastic deformation of the bone tissue, the root tip face 10 reaching the end or bottom of the guide hole can cause an increase in torque over a longer period of time, since even when idling, once the drill bit 1 begins to idle, the guide thread 30 of the drill bit 1 may tend to deform the bone tissue rather than cut it.

[0087] Additionally or alternatively, the drill core 20 may have at least a non-circular profile in a cross-section perpendicular to the longitudinal axis L. This configuration of the drill core 20 may also be twisted, i.e., the non-circular profile rotates about the longitudinal axis L in a cross-section along the coronal-root direction. Furthermore, and if present, the non-circular profile guide thread 30 and the non-circular profile drill core 20 may be twisted relative to each other (i.e., one or both are twisted about the longitudinal axis).

[0088] At the root tip (i.e., at the root tip face), the drill core 20 and preferably the portion forming the retaining arm 50 along the drill core 20 may have a circular profile. This circular profile coronally changes to a non-circular profile.

[0089] When preparing the bone recess at the bottom of the guide hole on the root tip face 10, the non-circular profile of the drill core causes the drill 1 to remain in place along its trajectory. The non-circular profile, combined with the groove 40 including the cutting edge 43, is configured to form the bone recess based on the cutting of bone tissue and the elastic deformation of the bone tissue. This elastic deformation can hold the drill 1 in place upon contact with the bone tissue on the root tip face 10. If the drill 1 continues to rotate, it also prevents wobbling of the drill 1 and thus prevents further cutting action of the drill 1.

[0090] The effects of non-circular profiles on the formation of recesses and the cutting behavior of drill bits are described in more detail in EP 21 208 105 A, which is incorporated herein by reference.

[0091] More specifically, the relationship between the groove 40 and the non-circular cross-section of the drill core 20 advantageously influences the way the drill 1 forms the desired bone recess by cutting and deforming bone tissue.

[0092] Figures 4 to 6 Cross-sectional views of drill bit 1 at different locations along the longitudinal axis L are illustrated. The cross-sectional views illustrate a cross-sectional view of drill bit 1 perpendicular to the longitudinal axis L, viewed from the root-crown direction. Each of these cross-sectional views shows the outline 3 of drill bit 1, which may include shape segments derived from features such as grooves 40 or guide threads 30.

[0093] For comparison, Figures 4 to 6 Each cross-sectional view includes the basic outline 25 of the drill core 20, that is, the outline of the drill core 20 representing its basic shape, without any additional features (such as the groove 40 or the guide thread 30). Figure 6 In the cross-sectional view, the basic shape 3 allows indication of where the outermost point 24' of the drill core 20 without the groove 40 will be located.

[0094] The cross-sectional shape 3 of the drill bit core 20 preferably includes at least one outermost point 24. The at least one outermost point 24 is located substantially at a first radial distance r1 from the longitudinal axis L. Therefore, the radial distance r1 at the outermost point 12 represents the maximum radial distance from a point on the basic shape 25 (or shape 3) to the longitudinal axis L.

[0095] exist Figures 4 to 6 In the drill core 20, the basic cross-sectional shape 25 includes three outermost points 24. However, any other number of outermost points 12 can be formed, such as one, two (i.e., elliptical), three (i.e., triangular-elliptical), four, five, or six outermost points 12. Preferably, the outermost points 12 are evenly distributed along the shape of the drill core 20.

[0096] Figures 4 to 6 Each of the cross-sectional views illustrates a cross-section at a different part of the drill bit 1 along the longitudinal axis L. In these cross-sectional views, as indicated by the curved arrows, the predetermined rotation direction of the drill bit 1 is defined in the counterclockwise direction.

[0097] The drill bit 1 may include at least a portion along the longitudinal axis L in the apical-coronal direction, wherein the diameter of the drill bit core 20 and / or the first radial distance r1 is increased. This increase preferably corresponds to an increase in the diameter of the dental implant (not shown) to be implanted into the recess formed by means of the drill bit 1.

[0098] Furthermore, the drill bit 1 may include at least a portion along the longitudinal axis L, wherein the diameter of the drill bit core 20 and / or the first radial distance r1 remain substantially the same. This portion may also be shaped to correspond to the implant to be placed.

[0099] At the coronal end 4 of the drill 1, which is configured to interact with bone tissue, the drill 1 can be shaped to have a size substantially the same as that of the dental implant at that location in the implanted state. At the root apex 2, the drill 1 can be adapted to be smaller in size than the dental implant. The latter is used to enhance the primary stability of the implant by inducing a pressure fit between the patient's bone tissue and the implant.

[0100] Typically, it is advantageous to adapt the shape of the drill bit 1 along the longitudinal axis L to the geometry of the dental implant to be inserted into the bone recess prepared with the drill bit 1. Preferably, this adaptation takes into account the type of bone that will be located near the implant after implantation. Specifically, in cartilage, the drill bit 1 is too small relative to the implant size used to support the anchorage of the implant within the bone tissue.

[0101] The (average) size of drill 1, which is essentially the same as that of the dental implant at the coronal end 4, reduces strain in the cortical bone tissue after implantation to prevent bone resorption and promote inward bone growth.

[0102] The smaller size of the drill bit 1 relative to the dental implant at the root tip 2 achieves good initial stability of the dental implant within the bone recess.

[0103] The non-circular drill core 20 includes at least one compression zone 27 and at least one relaxation zone 28 (see...). Figure 4 ).

[0104] In the predetermined rotation direction of the drill bit 1, at least one compression zone 27 extends along a portion of the cross-sectional shape of the drill bit core 20, starting from the innermost point 29a having a radial distance r3a from the longitudinal axis L, preferably extending to the outermost point 24 along the shape and at the maximum radial distance r1 between the shape and the longitudinal axis L.

[0105] Also in the predetermined rotational direction of drill bit 1, at least one relaxation zone 28 extends along a portion of the cross-sectional shape of drill core 20, starting from the outermost point 24 with a maximum radial distance r1 from the longitudinal axis L and ending at the innermost point 29b with a radial distance r3b from the longitudinal axis L. The distances r3a and r3b may be equal.

[0106] The shape between the innermost point 29 and the outermost point 24 of the compression zone 27 and / or relaxation zone 28 is preferably smooth (e.g., (only) curved). Nevertheless, either or both of zones 27 and 28 may have at least one straight sub-segment.

[0107] It should be noted that the cross-sectional shape of the drill core also includes more than one outermost point 24 (i.e., they form a circular line segment) positioned directly adjacent to each other, because all these outermost points 24 have a first radial distance r1 (maximum radial distance). The same applies to the innermost point 29 at the minimum radial distance r3 from the longitudinal axis L. Nevertheless, it is preferable to have a single outermost point 24 and / or a single innermost point 29.

[0108] The number of compression zones 27 in the cross-section of the drill core 20 can be approximately equal to the number of relaxation zones 28. This term is generally used in this document because either or both of zones 27 and 28 can be interrupted by a cutting zone 45, which will be described in more detail below.

[0109] In compression zone 27, drill bit 1 is configured to compress bone tissue in a radially outward direction, i.e., to apply a densifying or compacting effect to the bone tissue. As the drill bit rotates, predetermined points (not shown) in the bone tissue are pushed radially outward as the radial distance of the cross-section of drill bit core 20 increases from radial distance r3 to radial distance r1. This outward movement relative to the bone tissue results in the densification of the bone tissue.

[0110] In the relaxation zone, the drill bit 1 allows compressed bone tissue to recover by radially inward movement of the drill core 20's profile 3. In other words, as the drill bit rotates, predetermined points (not shown) in the bone tissue can follow radially inward as the radial distance of the drill core's profile decreases from the outermost point 24 to the innermost point 29.

[0111] Without being bound by theory, it has been found that high-density bone tissue (e.g., cortical bone) generally recovers faster than low-density bone tissue (e.g., cancellous bone). In other words, in the relaxation zone of drill bit 1, higher-density bone tissue relaxes and extends radially inward more quickly than lower-density bone tissue.

[0112] At least a portion of the cross-sectional shape of the drill bit core 20 is preferably non-circular (but preferably circular or curved). Therefore, at least a portion of the drill bit core 20 along the longitudinal axis L has at least a partially non-circular cross-section.

[0113] The cross-sectional shape of the drill core 20 may also be non-circular along its entire length or at least substantially entirely along its longitudinal axis L. For example, the non-circular shape may be elliptical or triangular-elliptical. However, other shapes of the non-circular shape are also possible, specifically substantially circular shapes. Nevertheless, and as discussed above, the drill core 20 may also include a cross-sectional shape that is substantially circular at least along a portion of the longitudinal axis L.

[0114] The non-circular shape allows for the definition of at least one compression zone 27 and a relaxation zone 28. Specifically, the portion of the cross-sectional shape of the drill core 20 from the minimum radial distance r3a to the maximum radial distance r1 in the predetermined rotational direction of the drill bit 1 is defined as the compression zone 27, i.e., it is configured to compress adjacent bone tissue. The portion of the cross-sectional shape of the drill core 20 from the maximum radial distance r1 to the minimum radial distance r3b in the predetermined rotational direction of the drill bit 1 is defined as the relaxation zone 28, i.e., it is configured to allow previously compressed bone tissue to relax. The shape of the non-circular shape 3 can be designed to define multiple compression zones 27 and relaxation zones 28 along the cross-sectional shape of the drill core 20.

[0115] The drill bit 1 can be constructed differently at four coronal apical locations, where it interacts with cortical bone tissue having a compact structure and relatively high density, and at the root apex, where it typically prepares cancellous bone tissue with a trabecular structure and generally lower density. Therefore, when preparing the bone recess for insertion of the dental implant, these different areas of bone tissue can be prepared in a single step. This avoids complex drilling procedures in most patients. Preferably, a guide drill can be used before the drill bit 1 to facilitate preparation.

[0116] The drill bit 1 includes a cutting portion that extends at least partially along (preferably along the entire) groove 40. Thus, at least a portion of the groove 40 can be configured as a non-cutting groove, i.e., a groove having an edge that does not form a cutting edge 43.

[0117] The cutting portion can exist along the longitudinal axis L from the root tip 2 to the coronal end 4 along substantially the entire length of the drill core 20, that is, along the portion configured to interact with bone tissue.

[0118] Preferably, the groove 40 extends along the longitudinal axis L over the entire length of the drill bit (operating portion). In other words, at least one first end of the groove is located at the root tip 2 of the drill bit, and a second end of the groove is located at the coronal end of the drill bit configured to interact with bone tissue. The groove 40 may extend continuously between the first end and the second end. The drill bit may include two or more grooves having the same features described above.

[0119] As previously described, the cutting portion preferably tapers gradually towards the root tip; that is, the cross-section of the cutting portion perpendicular to the longitudinal axis L decreases in size from the coronal end to the root tip. Therefore, as the drill bit penetrates the bone tissue, the cutting portion increases the size of the hole created by cutting adjacent bone tissue. If a guide thread 30 is present, the cutting motion is performed with a specific, stable feed.

[0120] The cutting portion can also be at least partially or completely constructed of dense bone tissue. Therefore, the cross-section of such a cutting portion includes a compression zone 27 and a relaxation zone 28. Thus, this cutting portion is configured to compress the bone tissue in the compression zone 27 while rotating in a predetermined rotational direction of the drill bit 1, and to allow the bone tissue to relax in the relaxation zone 28.

[0121] As described above, the contours along the compression zone 27 and the relaxation zone 28 and / or the transition between the compression zone and the relaxation zone are preferably (only) curved; that is, they may not include straight sections or discontinuities (except for the cutting zone 45). This has a positive effect on the structural integrity of the bone tissue processed by the drill bit 1.

[0122] However, at least a portion of the cutting section can also be configured as a cutting section without being constructed to compress bone tissue by rotation or in the direction of rotation. Such a cutting section is constructed without compression zone 27 and relaxation zone 28.

[0123] However, the cross-sectional shape of the drill core 20 along at least a portion or the entire cutting portion is preferably non-circular and includes a compression zone 27 and a relaxation zone 28. This results in a shape configured to have a compacting effect on bone tissue during rotation. Depending on the configuration of the non-circular shape, multiple compression and relaxation zones may be defined along the cross-sectional shape of the drill core 20.

[0124] If not constructed to be dense in the direction of rotation, the cross-sectional shape of the drill core 20 can be substantially circular. If the groove 40 and / or guide thread 30 are present, the cross-sectional shape of the cutting portion of bone tissue not constructed to be dense in the direction of rotation is substantially circular.

[0125] Along the cross-sectional shape of the cutting portion of the drill core 20, the cutting portion preferably includes at least one cutting zone 45, which includes a cutting point 44. The cutting zone 45 is defined by a groove 40, which forms a concave recess in the shape of the cutting portion and includes a cutting edge 43. Thus, the cutting portion includes at least one groove 40. As described above, the groove 40 is preferably formed as a recess or groove in the drill core 20 and extending along the drill core. Furthermore, the groove 40 may be straight, but preferably extends spirally around the drill core 20. The latter case distributes the cutting force along the circumference of the drill bit 1 and facilitates guidance during insertion.

[0126] Preferably, the cutting zone 45, including the cutting point 44, is located within the compression zone 27 of the shape 3 of the cutting portion of the drill bit, which is also configured for dense bone tissue. In this case, the shape of the compression zone 27 is interrupted by the cutting zone 45.

[0127] At least one cutting point 44 is located at a second radial distance r2 from the longitudinal axis L in a cross-sectional view of the drill core 20 along the cutting portion. The shape 3 of the cross-section of the drill core 20 along the cutting portion may include two or three pairs of outermost points 24 and cutting points 44, wherein each pair includes an outermost point 24 and a cutting point 44.

[0128] The cutting point 44 preferably represents a discontinuity along the shape 3 of the cutting portion. Therefore, the cutting point 44 includes a clearance angle, a lip angle, and a rake angle.

[0129] At least one cutting point 44 located at a second radial distance r2 allows for cutting bone tissue along a circle within the cross-section, the circle having a radius of a second radial distance r2 from the longitudinal axis L. If the second radial distance r2 is less than the first radial distance r1 of the outermost point 24 described in more detail below, the drill 1 is not configured to cut bone tissue in a region having a radial distance greater than the second radial distance r2.

[0130] Therefore, in at least a portion of the cutting portion along the longitudinal axis L, that is, in at least some of the cross-sections along the longitudinal axis L, the second radial distance r2 in the cross-section of the drill core 20 can be less than the first radial distance r1 of the outermost point 24. In other words, the drill bit 1 and the cutting portion may include a portion having a negative clearance angle along the longitudinal axis L.

[0131] Alternatively, in at least a portion of the cutting portion along the longitudinal axis L, the first radial distance r1 and the second radial distance r2 may also be substantially equal in the cross-section of the drill core 20. In other words, the outermost point 24 and the cutting point 44 may substantially coincide. In this case, the drill bit 20 and the cutting portion may include a portion along the longitudinal axis, wherein the cutting point 44 has a positive clearance angle.

[0132] The ratio between the first radial distance r1 of the outermost point 24 and the second radial distance r2 of the cutting point 44 can vary between the cross sections of the drill core 20 along the cutting portion.

[0133] In an embodiment where the second radial distance r2 is less than the first radial distance r1, the drill bit 1 and the cutting portion include a non-cutting zone 46, wherein the drill bit 1 is not configured to cut the bone (see...). Figure 4 (cross section).

[0134] The radial extension of the non-cutting zone 46 defines an annular region between the second radial distance r2 and the first radial distance r1. Within this non-cutting zone 46, the drill bit 1 is configured to optionally compress or allow bone tissue to relax, i.e., to apply force to the bone tissue in the radial direction without cutting it. As described above, in the compression zone 27, when the drill bit 1 rotates in a predetermined rotational direction, the bone tissue adjacent to the compression zone is pushed radially outward, while in the relaxation zone 28, the bone tissue is allowed to recover in the radially inward direction.

[0135] Unwilling to be bound by theory, drill bit 1 utilizes the observation that bone tissue with higher density recovers faster than bone tissue with lower density, i.e., it moves radially inward more quickly. After compressing the bone tissue in compression zone 27 in a radially outward direction, the compressed bone tissue recovers radially inward in relaxation zone 28. Due to the difference in recovery time, drill bit 1 has a bias toward cutting bone tissue with higher density (e.g., cortical bone tissue).

[0136] The allowable recovery time depends on the circumferential position of the cutting point 44 and the outermost point 24 (and the rotational rate and / or speed of the drill bit 1), and therefore on the position of the shape 3 along the cross-section of the drill core 20 relative to the compression zone 27 and relaxation zone 28 of the cutting point 44. Bone tissue that recovers to a radial distance less than the second radial distance r2 within the predetermined allowable recovery time will be cut at the next cutting point 44, while bone tissue that recovers to a point between the second radial distance r2 and the first radial distance r1 will not be cut at the next cutting point 44. Therefore, the cutting point 44 can cut bone tissue to different degrees depending on its characteristics, i.e., to a greater extent than cartilage tissue. This effect can be adjusted by the geometry of the drill core 20, i.e., the magnitude of the first radial distance r1 and the second radial distance r2 and their circumferential position.

[0137] When the second radial distance r2 is substantially equal to the first radial distance r1, the drill bit 1 and the cutting portion exhibit cutting behavior different from the cutting behavior described above. Since the cutting point 44 and the outermost point 24 substantially coincide, the cutting point 44 is located at the outermost radial position. In other words, all other points on the cross-sectional shape of the drill core 20 are located radially inward than the cutting point 44 (see...). Figure 5 and 6 Therefore, the drill bit 1 is not configured to compress or allow bone tissue to relax, but rather to cut bone tissue in a circular region defined by a first radial distance r1 or a second radial distance r2.

[0138] This is Figure 5 and Figure 6 The structure is illustrated below. Figure 6In the cross section, the theoretical outermost point 24' of the basic shape 25 of the drill core 20 (i.e., without considering the shape of the guide thread 30 and / or the cutting groove 40) and the outermost point 24 of the drill shape 3 coincide with the cutting point 44 of the drill shape 3.

[0139] It should be noted that the determination of the outermost point 24 of the drill bit profile 3 does not consider the guide thread 30 (if it exists) (see [reference]). Figures 4 to 6 (The cross-section). Furthermore, although a cross-section perpendicular to the longitudinal axis along the cutting portion may typically include a predetermined number of compression zones 27, relaxation zones 28, cutting zones 45, non-cutting zones 46, outermost points 24, and / or cutting points 44, some cross-sections may not include all of these features due to the influence of other structural features of the drill bit 10 (specifically, the guide thread 30) (see...). Figure 4 (Due to the lack of a relaxation zone and a portion of a compression zone in the guide thread 30).

[0140] Go to Figure 6 The theoretical outermost point 24' of the basic outline 25 of the drill core 20 is positioned along the cutting zone 45, where a groove 40 is formed along the outline 3 of the drill 1. Therefore, the theoretical outermost point 24' does not coincide with the outermost point 44 of the drill outline 3. However, in this case, the outermost point 24 also coincides with the cutting point 44.

[0141] It should be noted that Figure 6 The cross-section of the shape does not include the compression zone 27 or the relaxation zone 28. Although a part of the shape structurally corresponds to the relaxation zone 28, it cannot function as such a relaxation zone in terms of its functional configuration. In other words, the shape 3 lacks the compression zone 27 that functions to compress bone tissue, making it impossible for a relaxation zone 28 to exist that allows bone tissue previously compressed by the compression zone 27 of the drill bit 1 to relax.

[0142] From the above explanation, technicians will understand that the cutting behavior of drill bit 1 varies with the ratio between the first radial distance r1 and the second radial distance r2. Therefore, the cutting behavior of drill bit 1 along the longitudinal axis L can be adjusted, specifically taking into account different zones in the depth direction of the bone tissue at the implantation site.

[0143] Preferably, the cutting portion includes a first portion along the longitudinal axis L, wherein the second radial distance r2 of the cutting point 44 is less than the first radial distance r1 of the outermost point 24. In this first portion, the cutting portion may include a negative clearance angle at the cutting point 14. Furthermore, the first portion of the cutting portion may also be configured to condense bone tissue upon rotation. Therefore, the cross-sectional shape of the first portion of the cutting portion preferably includes at least one compression zone 27 and at least one relaxation zone 28.

[0144] The cutting portion may further include a second portion. In the second portion of the cutting portion, the second radial distance r2 may be substantially equal to the first radial distance r1. The second portion of the cutting portion may further include a cutting point 44 with a positive clearance angle. Preferably, the first portion of the cutting portion is located at the root tip of the second portion of the cutting portion.

[0145] Due to the difference in the ratio of the first radial distance r1 to the second radial distance r2 between the first and second parts of the cutting section, the cutting behavior of these parts is different from each other.

[0146] Specifically, the shape of the first part of the cutting section is configured to compress the bone tissue in the compression zone 27 when the drill bit rotates, allowing the bone tissue in the relaxation zone 28 to relax, and then cutting the bone tissue at the cutting point 44 in the cutting zone 45. Therefore, the amount of bone tissue cut during rotation depends on the relaxation characteristics of the bone tissue, i.e., the degree and speed at which the bone tissue relaxes after being compressed.

[0147] Not wanting to be bound by theory, the inventors observed that less cancellous bone with relatively low bone density was removed. Therefore, more cartilage tissue was retained to support the dental implant to be inserted.

[0148] The second part of the cutting section is not configured to compress bone tissue during rotation, but rather to cut bone tissue at the outermost point 24 corresponding to the cutting point 44.

[0149] Unwilling to be bound by theory, this feature is advantageous in cortical bone with relatively high bone density, where further densification of the bone tissue has a smaller impact. Therefore, the second part preferably creates a bone recess in the cortical region of the bone tissue, the size of which substantially corresponds to the size of the dental implant to be implanted, to avoid bone resorption and thus prevent the dental implant from growing inward more rapidly.

[0150] In the predetermined rotational direction of drill bit 1, the cutting point 44 along the first portion can be positioned along the shape of the drill bit's cross-section, such that during rotation, the cutting point 44 passes through the bone tissue position before or simultaneously with the outermost point 24. After the relative positions of the outermost point 24 and the cutting point 44 have changed along the shape to correspond to each other, the theoretical outermost point 24' can continue to change its relative position to pass through the bone tissue position before the cutting point. This results in a continuous change in the clearance angle from a negative clearance angle to a positive clearance angle.

[0151] As explained above, the geometry of drill bit 1, specifically the magnitude of the first radial distance r1 and the second radial distance r2, and their circumferential positions, define the cutting behavior of drill bit 1.

[0152] As described above, the cutting groove can extend helically around the drill bit 1. Therefore, the cutting point 44 also extends helically around the drill bit 1, specifically with a first pitch. The first pitch can be the same as the pitch of the cutting groove 15 (a cutting groove with a constant size), or it can be a different pitch than the pitch of the cutting groove (a cutting groove with a varying size). Specifically, the first pitch can be smaller than the pitch of the cutting groove (i.e., the size of the cutting groove increases in the root-to-crown direction).

[0153] To alter cutting performance, the outermost point 24 of the cross-section of the drill core 20 along the longitudinal axis L can be positioned along a helix having a second pitch around the longitudinal axis L. Alternatively, the outermost point 24 of these cross-sections can also be positioned along a substantially straight line preferably arranged parallel to the longitudinal axis L.

[0154] Preferably, the first pitch and the second pitch of the cutting point 44 and the outermost point 24 are different from each other. Specifically, the first pitch is smaller than the second pitch. Alternatively, the first pitch and the second pitch may be substantially equal.

[0155] In embodiments where the first and second pitches differ from each other, the relative circumferential positions of the outermost point 24 and the cutting point 44 vary along the longitudinal axis L of the cutting portion of the drill bit 1. Therefore, the cutting behavior of the drill bit 1 on different zones of the bone can be continuously adjusted along the longitudinal axis L.

[0156] Using the drill bit 1 according to this disclosure can reduce the complexity of the drilling scheme. Therefore, the sequential use of multiple different tools and complex drilling schemes can be avoided, and misalignment of sequentially used tools can be more easily prevented. Furthermore, the drill bit 1 allows for the prevention of the bone recess to be formed from being too large or too small.

[0157] Figure Labels

[0158] The following lists the reference numerals used in the specific embodiments and accompanying drawings. Throughout the drawings, these reference numerals refer to features having the same or equivalent functions and / or structures.

[0159] 1. Drill bit

[0160] 2. Root tip

[0161] 3. Appearance

[0162] 4. The coronal portion of the bone interaction region

[0163] 10 pointed surfaces

[0164] 11 Central Area

[0165] 12 arm-shaped radial extensions of the tip surface

[0166] 14 circumferential edges of the tip surface

[0167] 14a The tip of the arm on the root tip surface

[0168] 14b The side edge of the arm at the root tip.

[0169] 14c The opposite side edges of the arm of the root tip face

[0170] 20 Drill Cores

[0171] 21. Circumferential surface of the drill bit core

[0172] 22. Root tip edge of the drill bit core

[0173] 23 Chamfer

[0174] 24 outermost point

[0175] 24′ The outermost point of the theory

[0176] 25. Basic shape of the drill bit core

[0177] 27 Compression Area

[0178] 28 Relaxation Zone

[0179] 29 innermost point

[0180] 30 Guide thread

[0181] 40 grooves

[0182] 41 Concave surface

[0183] 42. Root tip edge of concave surface

[0184] 43 Cutting edge

[0185] 44 Cutting point

[0186] 45 Cutting Zone

[0187] 46 Non-cutting area

[0188] 50 Keeping arm

[0189] r1 First radial distance

[0190] r2 Second radial distance

[0191] r3 Minimum radial distance

[0192] L longitudinal axis

Claims

1. A drill bit (1), the drill bit comprising: Root tip (2), coronal end, and longitudinal axis (L) extending between the root tip and the coronal end. Drill core (20), the drill core extending along the longitudinal axis (L), At least two grooves (40), each groove being defined by a concave surface (41) forming a recess along the drill bit core (20); and Root tip surface (10), the root tip surface is located at the root tip (2), in -The root tip edge (42) of the concave surface (41) and - The root tip edge (22) of the drill bit core (20) The shape of the root tip face is defined such that the root tip face defines the contour of the retaining arm (50) at the root tip (2), each retaining arm being formed between the concave surfaces of adjacent grooves (40). And among them At least one of the at least two grooves (40) extends along the longitudinal axis over the entire length of the drill bit (1), which is configured to interact with bone tissue.

2. A drill bit (1), the drill bit comprising: Root tip (2), coronal end, and longitudinal axis (L) extending between the root tip and the coronal end. Drill core (20), the drill core extending along the longitudinal axis (L), At least two grooves (40), each groove being defined by a concave surface (41) forming a recess along the drill bit core (20); and Root tip surface (10), the root tip surface is located at the root tip (2), in -The root tip edge (42) of the concave surface (41) and - The root tip edge (22) of the drill bit core (20) The shape of the root tip facet is defined such that the root tip facet defines the outline of the retaining arm (50) at the root tip (2), each retaining arm being formed between the concave surfaces of adjacent grooves (40). The drill bit also includes a cutting portion that extends integrally along at least one of the at least two grooves (40) and is present along the longitudinal axis (L) from the root tip (2) to the coronal end of the portion of the drill bit configured to interact with bone tissue along substantially the entire length of the drill bit core (20).

3. The drill bit (1) according to claim 1 or 2, the drill bit further comprising at least one guide thread (30), the at least one guide thread (30) protruding from the drill core (20) and extending helically along the drill core (20), the guide thread preferably tapering gradually toward the root tip.

4. The drill bit (1) according to claim 3, wherein the radial height of the guide thread (30) is less than the radial extension of the profile of the retaining arm at the root tip face (10).

5. The drill bit (1) according to claim 3 or 4, wherein the guide thread (30) has a non-circular outer circumferential profile, wherein the non-circular outer circumferential profile is preferably a triangular elliptical profile.

6. The drill bit (1) according to any one of the preceding claims, wherein each retaining arm (50) has a radial extension greater than its circumferential width.

7. The drill bit (1) according to any one of the preceding claims, wherein the circumferential edge (14) of the root tip face (10) is arranged in a plane perpendicular to the longitudinal axis (L).

8. The drill bit (1) according to any one of the preceding claims, wherein the drill core (20) has a non-circular profile in a cross section perpendicular to the longitudinal axis (L), wherein the non-circular profile preferably rotates about the longitudinal axis (L) in the longitudinal direction of the drill bit (1) to produce a twisted non-circular drill core.

9. The drill bit (1) according to any one of the preceding claims, wherein the drill bit core (20) tapers gradually toward the root tip (2).

10. The drill bit (1) according to any one of the preceding claims, wherein the concave surface (41) of each groove (40) and the circumferential surface (21) of the drill core (20) form a cutting edge (43).

11. The drill bit (1) according to any one of the preceding claims, wherein at the root tip edge of each concave surface (41), the concave surface and the root tip face (10) partially form a cutting edge having a forward tilt angle and substantially no front clearance angle.

12. The drill bit (1) according to any one of the preceding claims, wherein the at least two grooves (40) extend spirally along the drill bit core (20).

13. The drill bit (1) according to claim 8, which is dependent on claim 5, wherein the non-circular profile of the drill bit core (20) and the non-circular outer circumferential profile of the guide thread (30) are circumferentially offset.

14. A method of creating an osteotomy using a drill bit (1), specifically according to any one of the preceding claims, wherein the method comprises: Drill holes using a directional drill; The drill bit (1) is used to enlarge the size of the hole for inserting the dental implant, the drill bit comprising: a drill core (20); At least two grooves (40), each groove being defined by a concave surface (41) forming a longitudinal recess along the drill bit core (20); a root tip face (10) located at the root tip portion (2) of the drill bit; and retaining arms (50) extending coronally from the root tip face, each retaining arm being formed between the concave surfaces of adjacent grooves (40). When the root tip face (10) contacts the bottom of the hole drilled by the guide drill, the retaining arm (50) generates a braking force to stop the rotation of the drill bit (1).

15. The method according to claim 13, wherein the tip of the guide drill has a diameter greater than the diameter of the root tip face (10).

Images