WO2007104842A1

WO2007104842A1 - Device for guiding an implant drill, and method for fitting an axial implant using this device

Info

Publication number: WO2007104842A1
Application number: PCT/FR2007/000274
Authority: WO
Inventors: Pierre Caillon
Original assignee: Obl
Priority date: 2006-03-15
Filing date: 2007-02-15
Publication date: 2007-09-20
Also published as: FR2898485B1; FR2898485A1

Abstract

The surgical implant guide (2) is placed astride a maxillary or mandibular arch. It comprises drill-bush holders (6) arranged in bores (4) of a template (3). Drill bushes (7), able to axially guide a drill (2), are inserted in the drill-bush holders (6). Each drill-bush holder (6) has the general shape of a ring (6) with a slit (8) opposite a notch (5) of the template (3). The width of the slit (8) and the width of the notch (5) are considerably less than the transverse dimension of the ring (6), while at the same time being greater than the diameter of the drill (2) or, alternatively, than the diameter of the implant that is to be fitted. The ring is alternatively provided with a rib (14) and/or with wings (15) on the edges of the slit (8). Application for guiding the drilling operation and for screwing in long axial implants in the sectors of the oral cavity where the axial clearance is limited, especially in the posterior sectors.

Description

DEVICE FOR GUIDING AN IMPLANT FOREST AND METHOD FOR INSTALLING AN AXIAL IMPLANT USING THE DEVICE

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a device for guiding an implant drill, and a method using this device for placing an axial implant in the bone of a maxillary or mandibular arch of a patient.

BACKGROUND OF THE INVENTION

Aesthetic considerations or therapeutic indications often lead to the replacement by prostheses of the missing teeth of a patient's dentition. The most common prostheses are still prostheses with dental or mucosal support, while the development of prostheses anchored in the mandible or maxillary • of the patient by means of one or more implants screwed into holes drilled into the bone tissue , or simply inserted into osteotomies.

Endosseous dental implants are divided into different categories according to their shapes and insertion modes.

A first category consists of axial implants, or more generally, implants with vertical insertion on the alveolar ridge. The system of axial screw implants most commonly used is the so-called "Branemark" system, named after its inventor, who disclosed it in France in application FR-2.032.287, published on November 27, 1970.

^• It is known to use modern techniques of medical imaging coupled with robotic techniques to simulate three-dimensional computer installation of this type of implant before any intervention, and manufacture a drilling template to guide the surgeon -dentist during the operation. The implementation of these techniques has significantly increased the rate of achieving good esthetic results, while decreasing the risk of postoperative complications. A method and device of this type for determining the ideal location of an axial implant, and designed for the precise placement thereof, are described in U.S. Patent No. 5,320,529, in the name of D. Pompa, published June 14, 1994. According to this method, a stereo lithographic model of the jaw bone is made from tomographic sections, and it allows the practitioner to simulate on this model the installation of prostheses. A surgical guide is made by molding the bone model and radiopaque models of implants in place, with their implant holders. Drill barrels of inner diameters corresponding to drills of different sizes are then placed in the impressions of the implant holders.

The guidance device of a drill described in US Pat. No. 5,743,916, in the name of A. Greenberg et al., Published on April 28, 1998, reproduces the previous principle of the use of drill guns of different diameters. interiors inserted in single diameter bores. An additional comfort element of use is constituted by a gun holder having a bar acting as a handle. The bar also stores the drill cannons like cartridges in a bandolier, and includes the indication of their sizes.

The method and the device described in the international patent application WO 03/071972, on behalf of the OBL company, published on September 4, 2003, are of the type of the two preceding ones, but differ in particular by fully exploiting the possibilities and advantages of an implant simulation on a computer, without using multiple templates, or molding from a real model of the bone. A second category of implants is that of lateral insertion implants in the jaw bones. These implants generally have a vertical shaft for supporting the prosthesis and a base perpendicular to the shaft, consisting of a plate or one or more disks. For example, an implant of this type having • a perforated rectangular plate is described in the French patent application FR-2302715, published October ^1, 1976 in the names of B. Clunet-Coste and J. Maneuf. This second category of implants has many advantages over the first, especially when the bone volume available for implantation is reduced, or when the opening of the oral cavity is too low to achieve axial implantation. In order to also perform with a very high precision complementary shape osteotomy of a lateral insertion implant, the applicant company has already proposed a customized implant surgical guide, which was the subject of the international patent application. WO2005 / 120385 published on December 22, 2005.

This drilling template is manufactured automatically from the tomographic sections of the patient's mandible, using implant simulation software.

The implant guide obtained is of the type of those placed astride the alveolar ridge of a maxillary or mandibular arch, and comprises at least one laterally open borehole.

Perfectly adapted to performing an implant-disk osteotomy, this guide device has at least a portion of the inner surface of a barrel and at least a portion of the outer surface of the cutter cooperating with one another and ensuring the maintenance axial axis of the cutter relative to the barrel.

By its very function, it is clear that a lateral maintenance of the cutter is not provided by this type of template. It is therefore not suitable for use with an implant drill for the placement of axial implants, although the possibility of lateral insertion of the drill can be an advantage when the opening of the oral cavity is weak.

International Patent Application WO 2004/075771 in the name of the company MATERIALISE, published on September 10, 2004, discloses an implant guide having at least one bore having a lateral opening allowing the insertion of a drill, to make this bore more accessible.

However, this last document only mentions the technical problem to be solved in functional terms, without specifying the technical specifications of the solution.

It is therefore apparent from the documents cited above that various devices for guiding drills or implant burs for the introduction of axial implants or disks are known from the state of the art.

However, none of these systems are designed for the use of axial implants in the case where the space of intervention offers the possibility of limited axial movement.

GENERAL DESCRIPTION OF THE INVENTION

The present invention thus relates to a device for guiding an implant drill whose characteristics are intended to fill a significant gap in the prior art. It relates specifically to an implant drill guide device, of the type of those placed astride a maxillary or mandibular arch, comprising at least one barrel holder arranged in at least one bore of substantially vertical axis of a jig and at least one removable drill barrel, adapted to guide axially this drill, and inserted into the corresponding gun holder.

The implant drill guide device according to the invention is remarkable, on the one hand, in that the barrel holder is of the general shape of a ring having a slot in an axial direction facing a substantially vertical notch of the template extending in a direction substantially horizontal, and, secondly, in that the width of the slot and the width of the notch are substantially less than the transverse dimension of the ring while being greater than the diameter of the drill to guide. It is also beneficial because the width of the slot of the ring and the width of the notch of the template are preferably greater than the diameter of a predetermined type of implant.

Advantageously, the ring is annular and the outer surface of the barrel is cylindrical.

Preferably, this ring also has externally at least one fin or longitudinal rib.

This rib extends radially and, alternatively or simultaneously, this fin preferably extends in a plane tangential to the ring from a straight edge of the slot.

The portion of the outer barrel template preferably comprises an outer shoulder, in a radial direction, cooperating with the circular edge vis-à-vis the gun holder. As for the portion of the inner barrel template, it preferably comprises an inner shoulder, in a radial direction, cooperating with the circular edge vis-à-vis said bore.

According to a variant of the invention, it takes advantage of the fact that the portion of the outer barrel template is provided with a bar extending in a substantially radial direction.

Preferably, this bar has an indication of the inner diameter of the barrel. The outer surface of the barrel advantageously comprises, meanwhile, an indication of the size of the gun carrier to which it corresponds.

Preferably, the width of the slot and the width of the notch, minus the value of a functional clearance, are chosen from the group of values 3.4 mm, 3.75 mm, 4.00 mm, 4, 2 mm, 5.00 mm, 6.00 mm. The present invention also relates to a method of placing an "axial implant in the bone of a maxillary or mandibular arch of a patient using the implant drill guide device described above.This method advantageously comprises the following steps: a) placement of the guiding device on a maxillary or mandibular arch, b) axial engagement of a suitable drill barrel on an implant drill of predetermined diameter, previously mounted on a drill holder, c) lateral engagement in the notch of the template and in the slot of the barrel holder of a part of the drill left visible by the drill pipe, d) axial engagement of the drill pipe in the barrel holder by axial sliding along the drill; ) performing drilling in the bone intended to receive the implant, f) lateral clearance through the slot of the ring and the notch of the template of the portion of the drill left visible by the drill pipe. the invention preferably further comprises a step of lateral engagement of the implant, mounted on an implant holder, in the notch of the template and in the slot of the ring, before screwing into the drilling of the bone.

These few essential specifications make it obvious to the practitioner the advantages provided by the implant drill guide device according to the invention, and by the method implementing it, with respect to the state of the prior art.

Detailed specifications of the invention, including examples of advantageous selections of dimensional characteristics of its constituent elements, and drills and implants for which it was designed, are given in the following description in conjunction with the accompanying drawings. It should be noted that these drawings have no other purpose than to illustrate the text of the description and do not constitute in any way a limitation of the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is an exploded view of a first embodiment of the guide device of an implant drill according to the invention, intended to be placed on a honeycomb of a mandible.

Figure 2 is an exploded view of an alternative embodiment of the guide device of an implant drill according to the invention. The figure shows the barrette of the barrel which is characteristic of this variant. Figure 3 shows the use of the alternative embodiment of the invention with a drill bit.

Figure 4 shows in detail a gun holder characteristic of another embodiment of the guide device of an implant drill according to the invention, Figure 5 shows the use with a drill.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

Figure 1 shows by way of example a guide device 1 of implanted implant drill developed for the installation of seven axial implants in a mandible. The placement of each of these endosseous implants usually requires the realization of a cylindrical osteotomy of vertical axis ZZ '.

This osteotomy is performed by the practitioner by means of a drill bit 2 (shown in Figure 3) engaged vertically in the mandible. The axis and depth of the osteotomy must respect the constraints of implant planning. This goal is achieved by means of a surgical guide 1 straddling the alveolar ridge, which allows the practitioner to achieve a very high operational precision by guiding the drill 2.

The guiding device 1 according to the invention consists of a template 3 obtained by a lithographic stereo process from the patient's scanner data and implant simulation. The jig 3 shown has seven cylindrical bores 4 of axes ZZ 'corresponding to the axes of the future implants. These The bores 4 have notches 5 substantially vertical and extending laterally in the jugular direction, that is to say towards the outside of the oral cavity. The bores 4 are provided with inserts 6, each in the form of an annular ring, glued to the inside of the jig 3. The outer wall of each of the inserts 6 has an annular groove which promotes anchoring in the bore 4. The inserts 6 are preferably made of titanium alloy, usually TA6V.

These inserts 6 enclose cylindrical drill guns 7 (only one is shown in Figure 1), and therefore act as gun holders. The drill guns 7 are preferably made of steel, such as I ¹ INOX 316L.

The barrel holders 6 are intended to provide guidance and axial retention of the drill 2, and also to allow the lateral engagement thereof by the notch 5 of the jig 3 without requiring significant opening of the jaws. To do this, each of the gun holders 6 has an axial slot 8 facing the corresponding notch 5 of the template 3.

The upper part of a barrel 7 has an outer shoulder 9 intended to limit its insertion into the corresponding gun holder 6.

For a similar purpose, the lower part of a barrel 7 has an internal shoulder 10 (shown in FIGS. 2 and 3) cooperating with the bottom of the corresponding bore 4 of the jig 3.

The width of the slot 8 of a gun holder 6 is greater than the diameter of the drill bit 2, so as to allow the passage of the latter, but substantially less than the diameter of the barrel holder 6 to ensure the guidance of a Likewise, the width of a notch 5 of the jig 3 is greater than the diameter of the drill bit 2, but substantially less than the diameter of the insert 6 to maintain the insert 6 in the bore 4 of the template 3.

According to the surgical practice, the osteotomy of the size necessary for the laying of an axial implant is carried out gradually by means of several drills 2 of increasing diameters.

The width of the slot 8 of the barrel holder 6 and the width of the notch 5 of the jig 3 are therefore adapted to the diameter of the drill 2 the strongest.

For example, for an implant of 3.75 mm or 4.00 mm, the diameters of the drills used successively are (in mm): 2.0 / 2.8 / 3.0 / 3.2 / 3.4.

In this case, the widths of the slot 8 and the notch 5, minus the value of a functional clearance, are of the order of 3.4 mm.

For implants of 5.00 mm or 6.00 mm, the series of drills 2 used respectively have successions of diameters (in mm): 2.0 / 2.8 / 3.0 / 3.2 / 3.4 / 4.2 or 2.0 / 2.8 / 3.0 / 3.2 / 3.4 / 4.2 / 5.0.

In these latter cases, the critical widths of the slot 8 and the notch 5 are respectively 4.2 mm and 5.0 mm.

During the operating sequence, the drills of each diameter are perfectly guided by the inserts 6 of the jig 3 by means of drill guns 7 having an outside diameter corresponding to the inside diameter of the insert 6, and an inside diameter corresponding to the drill bit. 2.

To facilitate gripping of these drill guns 7, according to a variant shown in Figures 2 and 3, a bar 11 is arranged at the top.

The strip 11, of flattened shape, extends in a radial direction. This shape advantageously allows the gripping bar 11 to have on one face an easily readable indication of the inner diameter of the barrel 7. The diameter of the adapted gun holder 6 is etched on the outer wall 12 of the central part of the barrel. 7.

The advantage of the implant drill guide 2 device 1 described above is to solve the difficulty of surgical access to the posterior sectors of the maxillary and the mandible by making it possible to place implants of the "long" type without deviating from the 'ZZ axis' of drilling. FIG. 3 clearly shows the improved surgical ergonomics of this ancillary instrumentation: the shank 13 of the drill bit 2 is in a position to be guided by the drill barrel 7 without it being necessary to raise the tip of the drill bit 2 to above the template 3 to introduce it into the barrel holder 6.

Indeed, the use of the guide device 1 described above ensures the desired advantageous result. After the guiding device has been placed astride the mandibular arch, and has been equipped with its barrel holders 6 - the slots 8 of said barrel holders being arranged opposite the notches 5 of the jigs 3 - each drill is obtained by axially engaging the drilling barrel 7 fitted to the drill bit 2 of appropriate predetermined diameter, previously mounted on a drill holder and then laterally engaging in the notch 5 and in the slot 8, the portion of the drill bit 2 left exposed by the drill gun 7.

The drilling barrel 7 is then engaged axially in the barrel holder 6, by axial sliding along the drill bit 2.

After execution of the drilling in the bone intended to receive the implant, the practitioner raises the drill holder, and consequently the drill barrel, so that he can then release laterally, always by the slot 8 and by the notch 5, the portion of the drill 2 left exposed by the drill pipe.

If the drilling is performed at a high speed, greater than 1000 rpm, recommended by some implant manufacturers, the ring 6 constituting the gun holder is subjected to significant mechanical and thermal stresses.

In this case, there is a risk that the ring 6 rotates in its bore 4, and thereby closes the notch 5 of the template 3, subsequently preventing the lateral disengagement of the drill 2.

There is also a risk of oscillations of the ring 6 in its bore 4, which can lead to the destruction thereof.

To overcome these disadvantages, the ring 6 is, in another variant of the guide device 1 of implant drill 2 according to the invention, provided with a longitudinal rib 14 and fins 15. As is clearly shown in FIG. 4, the rectangular fins are arranged on the edges of the slot 8, and extend in a plane tangential to the ring 6. A straight section of the barrel holder is in this way of the general form of an omega.

The outer rib 14 extends radially relative to the axis of symmetry of the ring 6, and longitudinally in the longitudinal plane of symmetry thereof.

Figure 5 shows the use of this other variant with a drill bit 2, and it is easily understood that the rib 14 and the fins 15 anchored in the jig 3 improve the axial retention of the ring 6 in the jig 3, and the block in rotation.

The improved maintenance of the ring 6 makes it possible to increase the width of the slot 8 and the width of the notch 5 of the template .3 to values greater than the diameter of the implant to be installed.

In this other variant, the widths of the slot 8 and the notch 5, minus the value of a functional clearance, are preferably of the order of the diameters of the implants used, that is to say 3, 75 mm, 4.00 mm, 5.00 mm or 6.00 mm.

This arrangement allows the lateral engagement of an implant in the notch 5 of the jig 3 and in the slot 8 of the gun holder S.

In this way, the template 3 used to guide the drill bit 2 can also be used by the practitioner to guide the screwing of an implant, particularly of the "long" type, mounted on its implant holder, even if the space at level of a posterior area of the maxillary and mandible is restricted.

The implant, via the implant holder, will be guided by and into the barrel holder 6 only in the last few millimeters of its stroke (usually the last 9 mm).

But this additional function of guiding the implant, even partial, is however very advantageous for the practitioner because, despite the use of a surgical guide, the implant surgery can experience several uncertainties as to its accuracy, given the many steps successive necessary. The reasons for these hazards are, on the one hand, the variable bone density (although it can be quantified beforehand during the analysis of the implant simulation) and, on the other hand, the difficulty of insertion centering " manual "of the implant.

The initial "manual" centering takes place within a barrel holder 6 of diameter much greater than that of the chosen implant, since the barrel holder 6 receives drill barrels 7 of successive diameters adapted to the bone density. encountered, as determined by image processing.

This centering insertion of the implant will be all the more difficult to succeed as the operator works in a posterior site of a maxillary or mandibular arch. The observed result is often obtained with a parallax defect, increased with a long implant.

The implant drill guide 2 of the invention is preferably intended for the posterior sectors of the oral cavity, and, in general, for the sectors where the axial displacement necessary for the laying of an axial implant is limited, but it can It can also be used in the lateral areas, or even in the anterior sectors of maxillary and mandibular arches.

Indeed, the barrel holder 6 provided with a side slot 8 brings in addition, whatever the situation of the intervention, three complementary advantages:

a first advantage is that this arrangement makes it possible to evaluate the portion of the keratinized gingiva (fibrous gingiva unlike the elastic alveolar mucosa according to the position of the mucogingival line) between the point of impact of the drill bit 2 and the mucogingival line. For this, it is sufficient to measure with a periodontal probe graduated said distance during the pre-operative endo-oral control of the anatomical adaptation of the guiding device 1. Then, it is necessary to report each recorded measurement at each remarkable point in replacing the guide device 1 on the plaster model of the arcade to be treated. A closed barrel guide does not allow you to perform this procedure which ensures the preservation of the keratinized gingiva by modifying the surgical protocol usually described with the use of an initial mucosal trephine and prior to the osteotomy of the edentulous ridge. a second advantage is that this arrangement makes it possible to increase the irrigation of the drill bit 2 usually in place on the handpiece (or contra-angle) held by the operator. Thus, the barrel holder 6 provided with a lateral slot 8 offers the possibility of additional irrigation provided by the instrumentalist, in his role of operating aid, with increased precision of sight and access thanks to the slot The third advantage is that this arrangement facilitates the prosthetic step, if the operator wishes to record the respective positioning of the implants at the end of the surgical procedure. The impression transfer will be screwed directly onto the implant, or onto a transmucosal abutment. Then, the joining of this same transfer with an immediate hardening plastic material (obtained by chemopolymerization and / or by photo-polymerization) will be facilitated by the slot 8 of the barrel holder 6 which provides sufficient space for the material to block the transfer of It should be noted that this joining of the impression transfer, by using the guiding device 1 as guardian, allows the repositioning of the implant replica on the reference plaster model, so that to manufacture the immediate prosthesis in the postoperative phase with greater precision.

It goes without saying that the invention is not limited to the only preferred embodiments described above.

These preferred embodiments relate to devices 1 intended to be placed preferably on the alveolar ridge of a mandibular arch.

Similar devices 1 according to the invention would also be intended to be placed on the alveolar ridge of a maxillary, or on the lining of an upper or mandibular arch, or on the teeth still present on this arch. The jaw direction of the notches specified above is a common direction in surgical practice. The other possible directions, that is to say, the palatal direction, the maxilla, and the lingual direction, in the mandible, are not described because of the lack of operative facility considering the usual anatomical obstacles recognized by the practitioners ( for example the tongue or a flat palatine vault).

The invention therefore embraces all the possible variants of embodiment that do not go beyond the scope defined by the claims below.

Claims

1) An implant drill guide device (1), of the type of those placed astride a maxillary or mandibular arch, comprising at least one barrel holder (6) arranged in at least one bore (4). substantially vertical axis (ZZ ') of a jig (3) and at least one removable drill barrel (7), able to axially guide said drill (2), and inserted into said corresponding barrel carrier (6), characterized in said barrel holder (6) is of the general shape of a ring (6) having a slot (8) in an axial direction facing a substantially vertical notch (5) of said template (3) extending in a substantially horizontal direction, and in that the width of said slot (8) and the width of said notch (5) are substantially less than the transverse dimension of said ring (6) while being greater than the diameter of said drill (2 ).

2) implant drill guide (1) (2) according to claim 1, characterized in that the width of said slot (8) and the width of said notch (5) are greater than the diameter of an implant type predetermined.

3) implant drill guide (1) (2) according to any one of claims 1 or 2, characterized in that said ring (6) is annular and the outer surface of said barrel (7) is shaped cylindrical.

4) Device for guiding (1) implant drill (2) according to any one of claims 1 to 3 above, characterized in that said ring (6) externally comprises at least one fin or longitudinal rib (14,15).

5) An implant drill guide (1) (2) according to claim 4, characterized in that said rib (14) extends radially. 6) implant drill guide (1) (2) according to claim 4, characterized in that said fin (15) extends in a plane tangential to said ring (6) from a straight edge of said slot (8).

7) An implant drill guide device (1) according to any one of the preceding claims 1 to 6, characterized in that the portion of said barrel (7) external to said template (3) comprises an external shoulder (9). ), in a radial direction, cooperating with a circular edge vis-à-vis said ring (-6).

8) implant drill guide (1) (2) according to any one of claims 1 to 7 above, characterized in that the portion of said barrel (7) inner said template (3) has an internal shoulder (10) , in a radial direction, cooperating with the circular edge vis-à-vis said bore (4).

9) An implant drill guide device (1) according to any one of claims 1 to 8 above, characterized in that the portion of said barrel (7) outside said template (3) is provided with a bar ( 11) extending in a substantially radial direction.

10) An implant drill guide (1) (2) according to claim 9, characterized in that said bar (11) has an indication of the inner diameter of said barrel (7).

11) An implant drill guide device (1) according to any one of the preceding claims 1 to 10, characterized in that the outer surface (12) of said barrel (7) includes an indication of the size of said holder. cannon (6).

12) Implant drill guide (1) according to any one of the preceding claims 1 to 11, characterized in that the width of said slot (8) and the width of said notch (5) minus the value of a functional clearance are selected from the group of values: 3.4 mm, 3.75 mm, 4, 00 mm, 4.2 mm, 5.0 mm, 6.00 mm.

13) Method for laying an axial implant in the bone of an upper or lower arch of a patient using the implant drill guide device (1) (2) according to any one of claims 1 to 12 previous.

14) A method of laying an axial implant according to claim 13 comprising the following steps: a) placing said guide device (1) straddling said arcade; b) axial engagement of a drill barrel (7) adapted to an implant drill bit (2) of predetermined diameter, previously mounted on a drill holder; c) lateral engagement in said notch (5) and said slot (8) of a portion of said drill (2) left visible by said drill pipe (7); d) axial engagement of said drill barrel (7) in said barrel holder (6) by axial sliding along said drill (2); e) performing a borehole in the bone for receiving said implant; f) lateral clearance by said slot (8) and said notch (5) of the portion of said drill (2) left visible by said drill pipe (7).

15) A method of laying an axial implant according to claim 14 further comprising a step of lateral engagement of said implant mounted on an implant holder in said notch (5) and in said slot (8) before screwing into said borehole. the bone.