EP3179956A2 - Process for the dynamic determining of the length of drill and its driver used in a dental implantation surgery - Google Patents

Process for the dynamic determining of the length of drill and its driver used in a dental implantation surgery

Info

Publication number
EP3179956A2
EP3179956A2 EP15832491.3A EP15832491A EP3179956A2 EP 3179956 A2 EP3179956 A2 EP 3179956A2 EP 15832491 A EP15832491 A EP 15832491A EP 3179956 A2 EP3179956 A2 EP 3179956A2
Authority
EP
European Patent Office
Prior art keywords
implant
height
drill
length
sleeve
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP15832491.3A
Other languages
German (de)
French (fr)
Other versions
EP3179956A4 (en
Inventor
Endre VARGA
Balázs BAGÓ
Balázs ERDÖHELYI
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Dicomlab Kft
Original Assignee
Dicomlab Kft
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dicomlab Kft filed Critical Dicomlab Kft
Publication of EP3179956A2 publication Critical patent/EP3179956A2/en
Publication of EP3179956A4 publication Critical patent/EP3179956A4/en
Withdrawn legal-status Critical Current

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C8/00—Means to be fixed to the jaw-bone for consolidating natural teeth or for fixing dental prostheses thereon; Dental implants; Implanting tools
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C1/00—Dental machines for boring or cutting ; General features of dental machines or apparatus, e.g. hand-piece design
    • A61C1/08—Machine parts specially adapted for dentistry
    • A61C1/082—Positioning or guiding, e.g. of drills
    • A61C1/084—Positioning or guiding, e.g. of drills of implanting tools
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C8/00—Means to be fixed to the jaw-bone for consolidating natural teeth or for fixing dental prostheses thereon; Dental implants; Implanting tools
    • A61C8/0089—Implanting tools or instruments
    • A61C8/009—Implanting tools or instruments for selecting the right implanting element, e.g. templates

Definitions

  • the invention relates to a process, which makes it possible to accomplish a dental implantation surgery using an implantation guide also in those cases, when the restricted oral opening of the patient would not allow this. Furthermore, the process according to the invention ensures that the implant locations are prepared for multiple implants having various lengths with the help of few drills having given lengths. The process according to the invention further ensures the shortest drill length necessary for the preparation of the implant location, the longest possible basic sleeve height, furthermore that the basic sleeve is placed the closest possible to the implant neck.
  • the basic principle of the dental implantation technologies performed with an implant guide is a suitably elaborated surgery device, which is supplemented with holes and can be placed into the mouth of the patient.
  • the implant locations suitable for receiving the dental implants can be prepared with perfect preciseness, planned size, position and depth, using specific, guided drills.
  • the applied drills are equipped with a so called stop, with which it can be ensured that a borehole longer than a given depth cannot be made.
  • the length of the drills also is longer than in case of the processes not using a guide.
  • a sleeve insert equipped with a short handle must also be used.
  • the clinician puts the sleeve insert compatible with the diameter of the drill to be actually used, into the appropriate basic sleeve of the implant guide, which is then removed from there after the drilling.
  • the implant guide, the longer dills and the sleeve inserts further decrease the space available for the accomplishment of the surgery. This constitutes one of the limitations of the technologies made with implant guides, since it depends on the mouth opening of the patient, if such a technology may be applied at all.
  • EP1 '795148 European Patent discloses an implant, which is provided with two threads, said document describing the structure of the implant, where the external thread extends up to an area of an implant neck.
  • US Patent document US 2014120498 discloses that the dental implant system comprises an implant that can be inserted into the bone of the jaw, where said implant is capable of receiving the dental mounting parts.
  • the implant guide is also located higher. Another limiting factor is that in the mouth of the patient, during the implantation surgery at the location of a rear tooth there is less space at the clinician disposal, as compared to that in case of a front tooth.
  • drill bits applicable in dental implant surgeries can be learned from WO 20131 '26569 international patent publication document.
  • Said document discloses that said drill bit comprises a shaft having a spiral flute and a cutting tip. According to the referred document, even 25 mm long drills may be applied in practice.
  • German patent document discloses a surgical drill applicable in dental implantation process.
  • the drill disclosed in the referred document has a so called collecting section between the attachment section and the drilling section, which is a longitudinal recess to collect the removed bone material.
  • the disclosed arrangement further increases the necessary length of the drill.
  • a number of systems are available for planning the implantation surgery. In general it can be stated that an implant manufacturer company usually elaborates a guide technology for its own implant system developed internally, further, softwares implementing various functions are also made available for the designing of implantation surgeries. These systems, however, support exclusively the designing and implementing of operations possible with the above- mentioned internally manufactured implants.
  • WO9426200 international patent publication document discloses a guiding device, which is adjustable according to the location and direction of the drilling necessary for the preparation of the implant location, thus there is no need to prepare a new implant guide in such a case, when the location or direction of the sleeve in the guide in not optimal.
  • the guiding device comprises a tubular guide made preferably from metal, which is suitable to guide the pilot drills with a diameter as short as 1-2 mm, and a support comprising said tubular guide.
  • Said tubular guide is connected to an axis, which makes possible to rotate the tubular guide within the support.
  • the inner support must be mounted within an outer support equipped with scores on its internal surface. The scores make it possible to displace the inner support, thus the position of the planned drill may be corrected.
  • the referred document does not offer a solution, with which the drill or sleeve with optimal length could be determined.
  • WO2007015140 international patent publication document discloses a process for the preparation of a dental implant guide.
  • the location of the planned implant must be designated in the prepared virtual three dimensional scan of the crania, which comprises the virtual reproduction of the teeth and/ or the soft tissues.
  • the planned location of the implants is designated by using markers, where the implant with selected size may be determined in such cross- sectional images, which fit to the longitudinal axis of the implant. Together with the virtual positioning of the implant the borehole receiving the sleeve in the guide, to be made with an axis identical with that of the implant is determined.
  • the process according to the document does not comprise an optimization step relating to the length of the drill or the height of the sleeve.
  • WO2009046391 international patent publication document also discloses a process for dental implantation, which includes among others a surgery design aided by a software.
  • Said software can display a three dimensional virtual presentation on the basis of the scans made about the oral structures of the patient (the gum and the teeth), and about the jaw bone.
  • the document discloses that the software makes it possible to spatially rotate the above-mentioned virtual presentation along three axes, to view the bone structure from various angles, furthermore, it supports the deterniining of the location, angle, depth and direction of the planned implant head.
  • the disclosed solution makes it possible to select an appropriate tooth to be fitted on a given implant from a database.
  • the disclosed process does not describe an optimization step concerning the length of the drill and the sleeve to be incorporated in the guide.
  • US 201 '41 '47806 US patent document discloses a dental implant guide independent from the manufacturers, furthermore a system serving its design.
  • the process according to said document is based on one hand on the fact that in practice it is not necessary to use a guide and surgical kit corresponding to all implant diameters, but rather it is sufficient to apply a guide designed to the so called preferred diameters.
  • the preparation of an implant location with 3.75 mm diameter can be accomplished with a 3.5 mm preferred diameter drill and a corresponding guide, and the enlargement of the borehole to 3.75 mm can be done without a guide.
  • the principle of the disclosed process is on the other hand the individual determination of distance between the top of the implant and the surface of the guide, the so called "elongation", from one implant to another.
  • the object of this is that if the sleeve is overstretched on the surface of the guide fitted on the oral structures, then not the length of the sleeve is reduced, but rather said elongation is increased.
  • the problem to be solved with the present invention is that accomplishment of the dental implantation surgery using an implant guide is not always possible due to the limited oral opening of the patient.
  • a further problem to be solved with the present invention is that the implant location for a number of implants with various lengths is to be prepared with the help of few drills with given length. When dete «mning of the necessary length of the drill, it is to be taken into consideration that the longer is the height of the basic sleeve incorporated in the implant guide, the more precise is guiding of the drill.
  • the above-mentioned objects are achieved by the present invention with the solution based on the discovery that the length of a drill necessary for the preparation of the implant location belonging to an implant may be minimized, if
  • the length of the designed implant is dynamically modified
  • the height of the basic sleeve to be incorporated in the implantation guide body is dynamically modified; and c) the height of the gum is determined taking the three dimensional environment of the implant area into consideration.
  • the invention relates to a process for designing of a dental implant surgery, said surgery meeting one, more or all of the preconditions selected from the group consisting of the following: a) the length of the designed implants can dynamically be modified; b) the height of the basic sleeves to be incorporated in the implantation guide body can dynamically be modified; c) the distance between the surface of the basic sleeve incorporated in the implant guide positioned opposite to the gum, being on the side at the oral cavity and the surface of the implant neck is minimal; d) the preparation of the implant location for the implant can be done using the shortest drill possible; e) the applicable guiding of the device, preferably the applicable basic sleeve is the longest possible; and f) the elaboration of implant locations with variable depths can be done using the least amount of devices possible, wherein the shortest drill length necessary for the elaboration of the implant location, and the longest, still acceptable height of the basic sleeve to be incorporated in the implant guide body are determined.
  • a preferred embodiment of the invention is the process as disclosed in Point 1, wherein the jaw bone and oral structures of the patient are digitized in advance.
  • a preferred embodiment of the invention is the process as disclosed in Point 1 or 2, wherein the shortest drill length necessary for the elaboration of the implant location, and the longest, still acceptable height of the guiding of the device, preferable of the basic sleeve to be incorporated in the implant guide body are determined by taking one, more or all of the following parameters into consideration:
  • the length of the guiding of the device preferably the possible heights of the basic sleeve to be incorporated in the implant guide body as an ordered set, wherein the bigger value precedes the smaller value;
  • a preferred embodiment of the invention is the process as disclosed in any of Points 1 to 3, wherein during the designing of the implant guide
  • the shortest length of the drill necessary for the preparation of the implant location belonging to the implant with the size, location, and direction of axis as designated in the preceding step b) is determined in such a manner that the distance between the surface of the guiding of the device, preferably the basic sleeve and the implant neck is minimized; furthermore, the biggest possible, still acceptable height of the guiding of the device, preferably the basic sleeve to be incorporated in the implant guide body is determined.
  • a preferred embodiment of the invention is the process as disclosed in Point 4, wherein during the designing of the implant guide, in step b) the height of the gum is determined in 8 different points around said axis at a distance measured from said axis and corresponding to the radius of the cylinder enclosing the implant, and the highest value is selected.
  • a preferred embodiment of the invention is the process as disclosed in Point 4 or 5, wherein step c) according to Point 4 is accomplished as follows:
  • step db if L dnll - H implant - H basjc sleeve - H shoulder ⁇ 3 ⁇ 4 m , then it is examined, if the last, that is the least value amongst the possible basic sleeve heights has been reached; e) ea) if the least possible basic sleeve height has not been reached, then the next basic sleeve height is selected, and the above steps are repeated starting from step c); or
  • step b if the least possible basic sleeve height has already been reached, then the next length of drill is selected, and the above steps are repeated starting from step b), in condition that the last, that is the longest length of drill has not already reached, otherwise there is no need to take further steps.
  • a preferred embodiment of the invention is the process as disclosed in any of Points 1 to 6, wherein the designing is made applying a computer and a software.
  • the second aspect of the present invention is the use of the process as disclosed in any one of Points 1 to 7 for the determination of the shortest length of drill necessary for the preparation of the implant location, furthermore, the highest possible, still acceptable height of the device, preferably the basic sleeve to be incorporated in the implant guide body, for each implant, individually.
  • a preferred embodiment of the invention is the use as disclosed in Point 8 for the preparation of multiple implant locations with variable depths, using 3 drills with variable lengths, said implant locations having 6 to 16 mm depths, and wherein the difference between the depths of the implant locations having different depths is at least 0.1 mm.
  • a preferred embodiment of the invention is the use as disclosed in Point 8 or 9, wherein the applied lengths of drills are selected from 20, 24 and 28 mm, and/or the heights of the applied basic sleeves are selected from 6, 5 and 4 mm.
  • the term "basic sleeve” has the following meaning: the basic sleeve is a hollow cylinder made from metal, fitting into the vent of the plastic implant guide, the function of which is the guiding of the drills and other devices.
  • the term "sleeve insert” has the following meaning: a hollow cylinder made from metal, equipped with a short handle and a shoulder, fitting into the basic sleeve, the function of which is the precise guiding of a drill with given diameter in the course of preparation of the implant location.
  • the handle makes it possible that the clinician puts the sleeve insert into the basic sleeve prior to the operation of drilling and remove the sleeve insert from the basic sleeve after the operation of drilling.
  • the said shoulder ensures that the sleeve insert fits to the baseic sleeve smoothly.
  • digital oral structures means the gum and the teeth.
  • implant neck means the part of the implant on the side of the oral cavity
  • top of implant means the farthest point of the implant from the oral cavity
  • the longest possible guiding can be ensured, furthermore, it can be ensured that said guiding is in the closest position to the implant neck, that is the distance of the implant neck and the guiding is the shortest possible.
  • the present invention relates to a process, said process meeting the following preconditions:
  • the length of the designed implants can dynamically be modified
  • the height of the basic sleeves to be incorporated in the implantation guide body can dynamically be modified
  • the preparation of the implant location for the implant can be done using the shortest drill possible
  • the shortest drill length necessary for the elaboration of the implant location, and the longest, still acceptable height of the basic sleeve to be incorporated in the implant guide body are determined.
  • a digitized impression prepared from the oral structures of the patient is at the clinician disposal.
  • the process according to the present invention includes that the size of the implant, its location and the direction of its axis is designated. Then knowing the size of the implant, its location and the direction of its axis, the height of the gum is determined around said axis at a distance measured from said axis and corresponding to the radius of the cylinder enclosing the implant.
  • the height of the gum is determined in 8 different points around said axis at a distance measured from said axis and corresponding to the radius of the cylinder enclosing the implant, and the highest value is selected.
  • the shortest length of the drill necessary for the preparation of the implant location belonging to the implant with the size, location, and direction of axis as designated in the preceding step is determined in such a manner that the distance between the surface of the basic sleeve and the implant neck is minimized, furthermore, the biggest possible, still acceptable height of the basic sleeve to be incorporated in the implant guide body is determined.
  • Said data may be determined by the step detailed as follows:
  • step c) ea) if the least possible basic sleeve height has not been reached, then the next basic sleeve height is selected, and the above steps are repeated starting from step c); or
  • step b if the least possible basic sleeve height has already been reached, then the next length of drill is selected, and the above steps are repeated starting from step b), in condition that the last, that is the longest length of drill has not already reached, otherwise there is no need to take further steps.
  • the shortest length of drill necessary for the preparation of the implant location may be determined for each implant, individually.
  • a preferred embodiment of the process according to the present invention ensures the preparation of multiple implant locations with variable depths, using 3 drills with variable lengths, said implant locations having 6 to 16 mm depths, and wherein the difference between the depths of the implant locations having different depths is at least 0.1 mm.
  • the applied lengths of drills are selected from 20, 24 and 28 mm.
  • the heights of the applied basic sleeves are selected from 6, 5 and 4 mm.
  • the present invention is illustrated by the following, non-limiting example.
  • the sizes of the starting basic sleeves were 4, 5 and 6 mm.
  • the height of the sleeve insert was 1 mm, the lengths of the drills were 20, 24 and 28 mm.
  • the height of the gum was 5 mm, and the length of the implant was 13 mm.
  • the calculation was started with a 20 mm drill, and a 6 mm basic sleeve as follows: L drill - H implant - H basic sleeve - H D ue to the 20-13-6-1 ⁇ 5 relation, the size of the basic sleeve was further decreased; due to the 20-13-5-1 ⁇ 5 relation the size of the basic sleeve was further decreased; due to the 20-13-4-1 ⁇ 5 relation the length of the drill was increased, and the starting was made with the 6 mm basic sleeve; due to the 24-13-6-1 ⁇ 5 the size of the basic sleeve was decreased, thus the 24-13-5-1 ⁇ 5 value was received. Accordingly, in the present case a 24 mm drill and a 5 mm basic sleeve were used.
  • the present invention offers a solution for the dynamic determination of the drill and basic sleeve to be used in a dental implant surgery.
  • the process according to the invention it can be ensured that the otherwise advantageous surgery using dental implant guide is available also in such a case, when the limited oral opening of the patient would not make possible to use the guide.
  • the invention according to the invention makes it possible to prepare the implant location for receiving the implant using the shortest drill possible, and the longest basic sleeve possible, being in the closest proximity to the implant neck.
  • the process according to the invention supports the solution that a small number of drills with given lengths be sufficient for the preparation of implant locations with various depths, which simplifies the designing and accomplishment of surgery plans.

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  • Health & Medical Sciences (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Dentistry (AREA)
  • Epidemiology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Orthopedic Medicine & Surgery (AREA)
  • Dental Prosthetics (AREA)
  • Dental Tools And Instruments Or Auxiliary Dental Instruments (AREA)

Abstract

The invention relates to a process, which makes it possible to accomplish a dental implantation surgery using an implantation guide also in those cases, when the restricted oral opening of the patient would not allow this. Furthermore, the process according to the invention ensures that the dental bone be prepared for multiple implants with varying lenghts with the help of few drills with given length. The process according to the invention further ensures the shortest drill length necessary for the elaboration of the dental bone, the longest possible guide-height, furthermore that the guide be placed the closest possible to the implant neck.

Description

PROCESS FOR THE DYNAMIC DETERMINING OF THE LENGTH OF DRILL AND ITS DRIVER USED IN A DENTAL IMPLANTATION SURGERY
The invention relates to a process, which makes it possible to accomplish a dental implantation surgery using an implantation guide also in those cases, when the restricted oral opening of the patient would not allow this. Furthermore, the process according to the invention ensures that the implant locations are prepared for multiple implants having various lengths with the help of few drills having given lengths. The process according to the invention further ensures the shortest drill length necessary for the preparation of the implant location, the longest possible basic sleeve height, furthermore that the basic sleeve is placed the closest possible to the implant neck.
DESCRIPTION OF THE STATE OF THE ART
The basic principle of the dental implantation technologies performed with an implant guide (said processes are also called navigation implantation) is a suitably elaborated surgery device, which is supplemented with holes and can be placed into the mouth of the patient. Through said holes the implant locations suitable for receiving the dental implants can be prepared with perfect preciseness, planned size, position and depth, using specific, guided drills. The applied drills are equipped with a so called stop, with which it can be ensured that a borehole longer than a given depth cannot be made. Thus, the length of the drills also is longer than in case of the processes not using a guide.
Furthermore, in order to guide the drills precisely, a sleeve insert equipped with a short handle must also be used. Before accomplishment of the drilling, the clinician puts the sleeve insert compatible with the diameter of the drill to be actually used, into the appropriate basic sleeve of the implant guide, which is then removed from there after the drilling.
Accordingly, during the surgery, the implant guide, the longer dills and the sleeve inserts further decrease the space available for the accomplishment of the surgery. This constitutes one of the limitations of the technologies made with implant guides, since it depends on the mouth opening of the patient, if such a technology may be applied at all.
Some implants possess self-cutting thread. For example, EP1 '795148 European Patent discloses an implant, which is provided with two threads, said document describing the structure of the implant, where the external thread extends up to an area of an implant neck. US Patent document US 2014120498 discloses that the dental implant system comprises an implant that can be inserted into the bone of the jaw, where said implant is capable of receiving the dental mounting parts.
There are also implants, where before the inserting of said implants, a threading operation must also be performed. A suitable device for such an operation is disclosed e.g. in DE102009031692 German patent document. In the disclosed arrangement the thread cutter is screwed into the prepared implant location through a navigation sleeve. The sleeve has got a complementary thread on its internal surface, and the thread cutter is equipped with a stop surface, which limits the cutting depth of the thread cutter.
If, for example, there are original teeth in the proximity of the surgery area, in such cases the implant guide is also located higher. Another limiting factor is that in the mouth of the patient, during the implantation surgery at the location of a rear tooth there is less space at the clinician disposal, as compared to that in case of a front tooth.
It is therefore apparent that during the planning and performing of the dental implantation surgeries it is a very important concern that the devices necessary for the accomplishment of the surgery is able to fit into the mouth of the patient. The free space available for the operations of the surgery will determine with how long drills the clinician can prepare the surgery location for the implant.
For example the drill bits applicable in dental implant surgeries can be learned from WO 20131 '26569 international patent publication document. Said document discloses that said drill bit comprises a shaft having a spiral flute and a cutting tip. According to the referred document, even 25 mm long drills may be applied in practice.
DE102009029714 German patent document discloses a surgical drill applicable in dental implantation process. The drill disclosed in the referred document has a so called collecting section between the attachment section and the drilling section, which is a longitudinal recess to collect the removed bone material. The disclosed arrangement further increases the necessary length of the drill. A number of systems are available for planning the implantation surgery. In general it can be stated that an implant manufacturer company usually elaborates a guide technology for its own implant system developed internally, further, softwares implementing various functions are also made available for the designing of implantation surgeries. These systems, however, support exclusively the designing and implementing of operations possible with the above- mentioned internally manufactured implants.
In the state of the art systems a simplification is used that distance between the surface of the implant from the view of the oral cavity, that is the distance between the implant neck and the surface of the basic sleeve built in the implant guide from the view of the oral cavity is considered to be fixed at a pre-determined value. This has the consequence that drills with different lengths must be assigned to each implant of a given implant system. The above- mentioned simplification cannot consider either, that an implant with given size where (frontal or distal region of the oral cavity), in what kind of position, and with what axis -direction is designed in the framework of the surgery planning. The implant location for receiving the implant can only be prepared with a drill having a length matching the length of the selected implant. This also has the consequence that with the drills belonging to the technology of a given implant manufacturer other implant location with different depth cannot be prepared. It can be demonstrated that the frequency of application of the implants with different sizes is in line with the Gauss distribution, that is, implants with medium size are most often used in the surgeries. However, due to the above-mentioned simplification (application of a fixed distance), the drills not having the optimal, the shortest possible length is used for these implants. This in turn may even result that due to the limited oral opening of the patient, the surgery with implant guide cannot be applied.
The state of the art system available at present do not either especially address the problem that the location of the teeth in distal position in an open mouth significandy limits the space available for the accomplishment of the surgery. It is a general practice in the implantation technologies that the clinician can select in general only from few, in general three implants with pre-determined length during the design of the surgery. In the course of designing and manufacturing of implant guides a similar simplification is used, when also few basic sleeves with given height to be incorporated in the implant guide body are taken into consideration. WO9426200 international patent publication document discloses a guiding device, which is adjustable according to the location and direction of the drilling necessary for the preparation of the implant location, thus there is no need to prepare a new implant guide in such a case, when the location or direction of the sleeve in the guide in not optimal. In the solution according to the referred document the guiding device comprises a tubular guide made preferably from metal, which is suitable to guide the pilot drills with a diameter as short as 1-2 mm, and a support comprising said tubular guide. Said tubular guide is connected to an axis, which makes possible to rotate the tubular guide within the support. The inner support must be mounted within an outer support equipped with scores on its internal surface. The scores make it possible to displace the inner support, thus the position of the planned drill may be corrected. The referred document does not offer a solution, with which the drill or sleeve with optimal length could be determined.
WO2007015140 international patent publication document discloses a process for the preparation of a dental implant guide. According to the disclosed process, the location of the planned implant must be designated in the prepared virtual three dimensional scan of the crania, which comprises the virtual reproduction of the teeth and/ or the soft tissues. In the solution according to the referred document the planned location of the implants is designated by using markers, where the implant with selected size may be determined in such cross- sectional images, which fit to the longitudinal axis of the implant. Together with the virtual positioning of the implant the borehole receiving the sleeve in the guide, to be made with an axis identical with that of the implant is determined. The process according to the document does not comprise an optimization step relating to the length of the drill or the height of the sleeve. WO2009046391 international patent publication document also discloses a process for dental implantation, which includes among others a surgery design aided by a software. Said software can display a three dimensional virtual presentation on the basis of the scans made about the oral structures of the patient (the gum and the teeth), and about the jaw bone. The document discloses that the software makes it possible to spatially rotate the above-mentioned virtual presentation along three axes, to view the bone structure from various angles, furthermore, it supports the deterniining of the location, angle, depth and direction of the planned implant head. In a given embodiment the disclosed solution makes it possible to select an appropriate tooth to be fitted on a given implant from a database. However, the disclosed process does not describe an optimization step concerning the length of the drill and the sleeve to be incorporated in the guide.
US 201 '41 '47806 US patent document discloses a dental implant guide independent from the manufacturers, furthermore a system serving its design. The process according to said document is based on one hand on the fact that in practice it is not necessary to use a guide and surgical kit corresponding to all implant diameters, but rather it is sufficient to apply a guide designed to the so called preferred diameters. For example, the preparation of an implant location with 3.75 mm diameter can be accomplished with a 3.5 mm preferred diameter drill and a corresponding guide, and the enlargement of the borehole to 3.75 mm can be done without a guide. The principle of the disclosed process is on the other hand the individual determination of distance between the top of the implant and the surface of the guide, the so called "elongation", from one implant to another. However, the object of this is that if the sleeve is overstretched on the surface of the guide fitted on the oral structures, then not the length of the sleeve is reduced, but rather said elongation is increased.
THE PROBLEM TO BE SOLVED WITH THE PRESENT INVENTION
The problem to be solved with the present invention is that accomplishment of the dental implantation surgery using an implant guide is not always possible due to the limited oral opening of the patient. A further problem to be solved with the present invention is that the implant location for a number of implants with various lengths is to be prepared with the help of few drills with given length. When dete«mning of the necessary length of the drill, it is to be taken into consideration that the longer is the height of the basic sleeve incorporated in the implant guide, the more precise is guiding of the drill.
OBJECT OF THE INVENTION From the review of the state of the art it is apparent that it fails to solve the problem of satisfying one, more or all of the following demands at the same time:
a) ensuring a process for the preparation of a dental implantation surgery, which, if possible, is applicable universally, and also in case of a limited oral opening of the patient;
b) ensuring a process, which is almost always applicable in the distant tract of the oral cavity, where, besides the size of the opening, the presence of the teeth present in the neighbouring position or in the opposite jaw bone also constitutes a spatial limit during the operations; c) ensuring a process for the application of the shortest drill length necessary for the formation of the implant location, and for the use of said drill;
d) making possible the use of drill kits comprising as small number of drills, as it is possible; e) ensuring of a device for a surgery design, which also determines and optimizes the lengths of the drills to be used during the surgeries;
f) making it unnecessary that drills with different lengths should be assigned to each implant of an implant system; and
g) making it possible to prepare of a implant location with various depth using given surgery drills.
The accomplishment of the above objects required the comprehensive analysis and modelling of a number of factors of a complex problem, as a result of which the present inventors has accomplished the present invention.
THE DISCOVERY SERVING AS PRINCIPLE OF THE PRESENT INVENTION
The above-mentioned objects are achieved by the present invention with the solution based on the discovery that the length of the drill to be used must be miriimized taking the condition into consideration that the basic sleeve incorporated in the implant guide is to be as long as it is possible.
Furthermore, the above-mentioned objects are achieved by the present invention with the solution based on the discovery that the length of a drill necessary for the preparation of the implant location belonging to an implant may be minimized, if
a) the length of the designed implant is dynamically modified;
b) the height of the basic sleeve to be incorporated in the implantation guide body is dynamically modified; and c) the height of the gum is determined taking the three dimensional environment of the implant area into consideration.
BRIEF DESCRIPTION OF THE PRESENT INVENTION
1. In its first aspect the invention relates to a process for designing of a dental implant surgery, said surgery meeting one, more or all of the preconditions selected from the group consisting of the following: a) the length of the designed implants can dynamically be modified; b) the height of the basic sleeves to be incorporated in the implantation guide body can dynamically be modified; c) the distance between the surface of the basic sleeve incorporated in the implant guide positioned opposite to the gum, being on the side at the oral cavity and the surface of the implant neck is minimal; d) the preparation of the implant location for the implant can be done using the shortest drill possible; e) the applicable guiding of the device, preferably the applicable basic sleeve is the longest possible; and f) the elaboration of implant locations with variable depths can be done using the least amount of devices possible, wherein the shortest drill length necessary for the elaboration of the implant location, and the longest, still acceptable height of the basic sleeve to be incorporated in the implant guide body are determined.
2. A preferred embodiment of the invention is the process as disclosed in Point 1, wherein the jaw bone and oral structures of the patient are digitized in advance.
3. A preferred embodiment of the invention is the process as disclosed in Point 1 or 2, wherein the shortest drill length necessary for the elaboration of the implant location, and the longest, still acceptable height of the guiding of the device, preferable of the basic sleeve to be incorporated in the implant guide body are determined by taking one, more or all of the following parameters into consideration:
a) the position of the implant neck;
b) the surface of the digitized oral structure;
c) the length of the implant;
d) the length of the guiding of the device, preferably the possible heights of the basic sleeve to be incorporated in the implant guide body as an ordered set, wherein the bigger value precedes the smaller value;
e) the possible lengths of the drill as an ordered set, wherein the smaller value precedes the bigger value; and f) optionally, if the device includes a sleeve insert, the height of the shoulder of said sleeve insert.
4. A preferred embodiment of the invention is the process as disclosed in any of Points 1 to 3, wherein during the designing of the implant guide
a) the size of the implant, its location and the direction of its axis is designated;
b) knowing the size of the implant, its location and the direction of its axis, the height of the gum is determined around said axis at a distance measured from said axis and corresponding to the radius of the cylinder enclosing the implant;
c) the shortest length of the drill necessary for the preparation of the implant location belonging to the implant with the size, location, and direction of axis as designated in the preceding step b) is determined in such a manner that the distance between the surface of the guiding of the device, preferably the basic sleeve and the implant neck is minimized; furthermore, the biggest possible, still acceptable height of the guiding of the device, preferably the basic sleeve to be incorporated in the implant guide body is determined.
5. A preferred embodiment of the invention is the process as disclosed in Point 4, wherein during the designing of the implant guide, in step b) the height of the gum is determined in 8 different points around said axis at a distance measured from said axis and corresponding to the radius of the cylinder enclosing the implant, and the highest value is selected.
6. A preferred embodiment of the invention is the process as disclosed in Point 4 or 5, wherein step c) according to Point 4 is accomplished as follows:
a) the shortest possible length of the drill is selected;
b) the longest possible height of basic sleeve is selected;
c) the height of the implant (H^ lant), the height of the basic sleeve (Hbasic sleeve) and the height of the shoulder of the sleeve insert (Hshouldet) are subtracted from the length of the drill (Ldrill), then the received value is compared with the height of the gum determined taking the three dimensional environment into consideration (Hg^J;
d) da) if Ldrill - Himplant - Hbasic sleevc - Hshoulder > H^, then the actual height of the basic sleeve and length of drill is considered to be the sought value, and no further step is taken; or
db) if Ldnll - Himplant - Hbasjc sleeve - Hshoulder < ¾m, then it is examined, if the last, that is the least value amongst the possible basic sleeve heights has been reached; e) ea) if the least possible basic sleeve height has not been reached, then the next basic sleeve height is selected, and the above steps are repeated starting from step c); or
eb) if the least possible basic sleeve height has already been reached, then the next length of drill is selected, and the above steps are repeated starting from step b), in condition that the last, that is the longest length of drill has not already reached, otherwise there is no need to take further steps.
7. A preferred embodiment of the invention is the process as disclosed in any of Points 1 to 6, wherein the designing is made applying a computer and a software.
8. The second aspect of the present invention is the use of the process as disclosed in any one of Points 1 to 7 for the determination of the shortest length of drill necessary for the preparation of the implant location, furthermore, the highest possible, still acceptable height of the device, preferably the basic sleeve to be incorporated in the implant guide body, for each implant, individually.
9. A preferred embodiment of the invention is the use as disclosed in Point 8 for the preparation of multiple implant locations with variable depths, using 3 drills with variable lengths, said implant locations having 6 to 16 mm depths, and wherein the difference between the depths of the implant locations having different depths is at least 0.1 mm.
10. A preferred embodiment of the invention is the use as disclosed in Point 8 or 9, wherein the applied lengths of drills are selected from 20, 24 and 28 mm, and/or the heights of the applied basic sleeves are selected from 6, 5 and 4 mm.
DETAILED DESCRIPTION OF THE INVENTION
In the context of the present invention the term "basic sleeve" has the following meaning: the basic sleeve is a hollow cylinder made from metal, fitting into the vent of the plastic implant guide, the function of which is the guiding of the drills and other devices.
In the context of the present invention the term "sleeve insert" has the following meaning: a hollow cylinder made from metal, equipped with a short handle and a shoulder, fitting into the basic sleeve, the function of which is the precise guiding of a drill with given diameter in the course of preparation of the implant location. The handle makes it possible that the clinician puts the sleeve insert into the basic sleeve prior to the operation of drilling and remove the sleeve insert from the basic sleeve after the operation of drilling. The said shoulder ensures that the sleeve insert fits to the baseic sleeve smoothly. In the context of the present invention the term "digitized oral structures" means the gum and the teeth.
In the context of the present invention the term "implant neck" means the part of the implant on the side of the oral cavity, and the term "top of implant" means the farthest point of the implant from the oral cavity.
With the process according to the present invention the longest possible guiding can be ensured, furthermore, it can be ensured that said guiding is in the closest position to the implant neck, that is the distance of the implant neck and the guiding is the shortest possible.
With the process according to the present invention it can be ensured that the shortest length of drill is at least such that the length of drill to be used in a surgery accomplished without using of an implant guide. Accordingly, the present invention relates to a process, said process meeting the following preconditions:
a) the length of the designed implants can dynamically be modified;
b) the height of the basic sleeves to be incorporated in the implantation guide body can dynamically be modified;
c) the distance between the surface of the basic sleeve incorporated in the implant guide positioned opposite to the gum, being on the side at the oral cavity and the surface of the implant neck is minimal;
d) the preparation of the implant location for the implant can be done using the shortest drill possible;
e) the applicable basic sleeve is the longest possible; and
f) the elaboration of implant locations with variable depths can be done using the least amount of devices possible. In practicing the process according to the present invention the following parameters are taken into consideration:
a) the position of the implant neck;
b) the surface of the digitized impression;
c) the length of the implant;
d) the possible heights of the basic sleeve to be incorporated in the implant guide body as an ordered set, wherein the bigger value precedes the smaller value;
e) the possible lengths of the drill as an ordered set, wherein the smaller value precedes the bigger value; and
f) the height of the shoulder of said sleeve insert.
By the process according to the present invention based on the above-mentioned parameters the shortest drill length necessary for the elaboration of the implant location, and the longest, still acceptable height of the basic sleeve to be incorporated in the implant guide body are determined.
It is a precondition of the process according to the present invention that a digitized impression prepared from the oral structures of the patient is at the clinician disposal. The process according to the present invention includes that the size of the implant, its location and the direction of its axis is designated. Then knowing the size of the implant, its location and the direction of its axis, the height of the gum is determined around said axis at a distance measured from said axis and corresponding to the radius of the cylinder enclosing the implant.
In a preferred embodiment of the invention the height of the gum is determined in 8 different points around said axis at a distance measured from said axis and corresponding to the radius of the cylinder enclosing the implant, and the highest value is selected. In the process according to the invention the shortest length of the drill necessary for the preparation of the implant location belonging to the implant with the size, location, and direction of axis as designated in the preceding step is determined in such a manner that the distance between the surface of the basic sleeve and the implant neck is minimized, furthermore, the biggest possible, still acceptable height of the basic sleeve to be incorporated in the implant guide body is determined. Said data may be determined by the step detailed as follows:
a) the shortest possible length of the drill is selected;
b) the longest possible height of basic sleeve is selected;
c) the height of the implant (Himplan[), the height of the basic sleeve (Hbasic sIeeve) and the height of the shoulder of the sleeve insert (Hshou,dec) are subtracted from the length of the drill (LdriU), then the received value is compared with the height of the gum determined taking the three dimensional environment into consideration (H „);
d) da) if Ldn!1 - Himplant - Hbasic sleeve - Hshoulder > Hgum, then the actual height of the basic sleeve and length of drill is considered to be the sought value, and no further step is taken; or
db) if L drui - Himpiant - HbaS1c sieeve " H shouider≤ ¾m) then it is examined, if the last, that is the least value amongst the possible basic sleeve heights has been reached;
e) ea) if the least possible basic sleeve height has not been reached, then the next basic sleeve height is selected, and the above steps are repeated starting from step c); or
eb) if the least possible basic sleeve height has already been reached, then the next length of drill is selected, and the above steps are repeated starting from step b), in condition that the last, that is the longest length of drill has not already reached, otherwise there is no need to take further steps.
By the process according to the present invention the shortest length of drill necessary for the preparation of the implant location, furthermore, the highest possible, still acceptable height of the basic sleeve to be incorporated in the implant guide body, may be determined for each implant, individually.
A preferred embodiment of the process according to the present invention ensures the preparation of multiple implant locations with variable depths, using 3 drills with variable lengths, said implant locations having 6 to 16 mm depths, and wherein the difference between the depths of the implant locations having different depths is at least 0.1 mm.
In a preferred embodiment of the process according to the present invention the applied lengths of drills are selected from 20, 24 and 28 mm. In a preferred embodiment of the process according to the present invention the heights of the applied basic sleeves are selected from 6, 5 and 4 mm. EXAMPLE
The present invention is illustrated by the following, non-limiting example. The sizes of the starting basic sleeves were 4, 5 and 6 mm. The height of the sleeve insert was 1 mm, the lengths of the drills were 20, 24 and 28 mm. The height of the gum was 5 mm, and the length of the implant was 13 mm. In the process according to the invention the calculation was started with a 20 mm drill, and a 6 mm basic sleeve as follows: Ldrill - Himplant - Hbasic sleeve - H Due to the 20-13-6-1 < 5 relation, the size of the basic sleeve was further decreased; due to the 20-13-5-1 < 5 relation the size of the basic sleeve was further decreased; due to the 20-13-4-1 < 5 relation the length of the drill was increased, and the starting was made with the 6 mm basic sleeve; due to the 24-13-6-1 < 5 the size of the basic sleeve was decreased, thus the 24-13-5-1≥ 5 value was received. Accordingly, in the present case a 24 mm drill and a 5 mm basic sleeve were used.
INDUSTRIAL APPLICABILITY
The present invention offers a solution for the dynamic determination of the drill and basic sleeve to be used in a dental implant surgery. By the process according to the invention it can be ensured that the otherwise advantageous surgery using dental implant guide is available also in such a case, when the limited oral opening of the patient would not make possible to use the guide. On one hand, the invention according to the invention makes it possible to prepare the implant location for receiving the implant using the shortest drill possible, and the longest basic sleeve possible, being in the closest proximity to the implant neck. On the other hand, the process according to the invention supports the solution that a small number of drills with given lengths be sufficient for the preparation of implant locations with various depths, which simplifies the designing and accomplishment of surgery plans.

Claims

WHAT IS CLAIMED IS
1. Process for designing of a dental implant surgery, said surgery meeting one, more or all of the preconditions selected from the group consisting of the following: a) the length of the designed implants can dynamically be modified; b) the height of the basic sleeves to be incorporated in the implantation guide body can dynamically be modified; c) the distance between the surface of the basic sleeve incorporated in the implant guide positioned opposite to the gum, being on the side at the oral cavity and the surface of the implant neck is minimal; d) the preparation of the implant location for the implant can be done using the shortest drill possible; e) the applicable guiding of the device, preferably the applicable basic sleeve is the longest possible; and f) the elaboration of implant locations with variable depths can be done using the least amount of devices possible, characterized in that the shortest drill length necessary for the elaboration of the implant location, and the longest, still acceptable height of the basic sleeve to be incorporated in the implant guide body are determined.
2. The process as claimed in Claim 1, characterized in that the jaw bone and oral structures of the patient are digitized in advance.
3. The process as claimed in Claim 1 or 2, characterized in that the shortest drill length necessary for the elaboration of the implant location, and the longest, still acceptable height of the guiding of the device, preferable of the basic sleeve to be incorporated in the implant guide body are determined by taking one, more or all of the following parameters into consideration:
a) the position of the implant neck;
b) the surface of the digitized oral structure;
c) the length of the implant;
d) the length of the guiding of the device, preferably the possible heights of the basic sleeve to be incorporated in the implant guide body as an ordered set, wherein the bigger value precedes the smaller value;
e) the possible lengths of the drill as an ordered set, wherein the smaller value precedes the bigger value; and
f) optionally, if the device includes a sleeve insert, the height of the shoulder of said sleeve insert.
4. The process as claimed in any of Claims 1 to 3, characterized in that during the designing of the implant guide
a) the size of the implant, its location and the direction of its axis is designated;
b) knowing the size of the implant, its location and the direction of its axis, the height of the gum is determined around said axis at a distance measured from said axis and corresponding to the radius of the cylinder enclosing the implant;
c) the shortest length of the drill necessary for the preparation of the implant location belonging to the implant with the size, location, and direction of axis as designated in the preceding step b) is determined in such a manner that the distance between the surface of the guiding of the device, preferably the basic sleeve and the implant neck is minimized; furthermore, the biggest possible, still acceptable height of the guiding of the device, preferably the basic sleeve to be incorporated in the implant guide body is determined.
5. The process as claimed in Claim 4, characterized in that during the designing of the implant guide, in step b) the height of the gum is determined in 8 different points around said axis at a distance measured from said axis and corresponding to the radius of the cylinder enclosing the implant, and the highest value is selected.
6. The process as claimed in Claim 4 or 5, characterized in that step c) according to Claim 4 is accomplished as follows:
a) the shortest possible length of the drill is selected;
b) the longest possible height of basic sleeve is selected;
c) the height of the implant (Himplant), the height of the basic sleeve (Hbasic s,eeve) and the height of the shoulder of the sleeve insert(Hshou,dei) are subtracted from the length of the drill (Ldri„), then the received value is compared with the height of the gum determined taking the three dimensional environment into consideration (H „,);
d) da) if Ldnll - Himplant - Hbasic slecve - Hshoulder > H^, then the actual height of the basic sleeve and length of drill is considered to be the sought value, and no further step is taken; or
db) if Ldnll - H]mplant - Hbasic sleeve - Hshoulder < H^, then it is examined, if the last, that is the least value amongst the possible basic sleeve heights has been reached;
e) ea) if the least possible basic sleeve height has not been reached, then the next basic sleeve height is selected, and the above steps are repeated starling from step c); or
eb) if the least possible basic sleeve height has already been reached, then the next length of drill is selected, and the above steps are repeated starting from step b), in condition that the last, that is the longest length of drill has not already reached, otherwise there is no need to take further steps.
7. The process as claimed in any of Claims 1 to 6, characterized in that the designing is made applying a computer and a software.
8. The use of the process as claimed in any one of Claims 1 to 7 for the determination of the shortest length of drill necessary for the preparation of the implant location, furthermore, the highest possible, still acceptable height of the device, preferably the basic sleeve to be incorporated in the implant guide body, for each implant, individually.
9. The use as claimed in Claim 8 for the preparation of multiple implant locations with variable depths, using 3 drills with variable lengths, said implant locations having 6 to 16 mm depths, and wherein the difference between the depths of the implant locations having different depths is at least 0.1 mm.
10. The use as claimed in Claim 8 or 9, wherein the applied lengths of drills are selected from 20, 24 and 28 mm, and/or the heights of the applied basic sleeves are selected from 6, 5 and 4 mm.
EP15832491.3A 2014-08-12 2015-08-11 Process for the dynamic determining of the length of drill and its driver used in a dental implantation surgery Withdrawn EP3179956A4 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
HU1400388A HU230967B1 (en) 2014-08-12 2014-08-12 Process for dynamically determining length of drill used in tooth implantation operation and that of guiding
PCT/HU2015/050007 WO2016024140A2 (en) 2014-08-12 2015-08-11 Process for the dynamic determining of the length of drill and its driver used in a dental implantation surgery

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EP3179956A2 true EP3179956A2 (en) 2017-06-21
EP3179956A4 EP3179956A4 (en) 2018-07-18

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HU (1) HU230967B1 (en)
WO (1) WO2016024140A2 (en)

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Publication number Priority date Publication date Assignee Title
US6814575B2 (en) * 1997-02-26 2004-11-09 Technique D'usinage Sinlab Inc. Manufacturing a dental implant drill guide and a dental implant superstructure
US7153132B2 (en) * 2005-05-23 2006-12-26 Tedesco James L Mini-dental implant surgical stent
GB0514554D0 (en) * 2005-07-15 2005-08-24 Materialise Nv Method for (semi-) automatic dental implant planning
EP2397102A1 (en) * 2007-08-22 2011-12-21 Straumann Holding AG Drill guide
EP3000430B1 (en) * 2008-04-16 2017-11-15 Biomet 3i, LLC Method of virtually developing a surgical guide for dental implant

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HU230967B1 (en) 2019-06-28
HUP1400388A2 (en) 2016-02-29
WO2016024140A2 (en) 2016-02-18
EP3179956A4 (en) 2018-07-18
WO2016024140A3 (en) 2016-05-19

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