FR3002134A1 - Endo-osseous implant device for insertion in housing placed in bone structure in e.g. dental field, has anchoring unit in engagement with bone structure and for translation of body for direct engagement of structure with support elements - Google Patents

Abstract

The device has a longitudinal body (10) that is arranged in an approximately cylindrical or cylindro-conical form, where the body is arranged with a longitudinal axis (L) and extending between a set of ends. A positioning head (20) is arranged on a level of one of the set of ends. An anchoring unit (30) is arranged in direct engagement with a bone structure and for translation of the longitudinal body for direct engagement of the bone structure with a set of support elements of the positioning head. An independent claim is also included for a gauge for installation of an implant device.

Description

FIELD OF THE INVENTION The present invention relates to the field of endo-osseous implantology, and more particularly the primary stabilization of these endosseous implants. It relates more particularly to an implant that can be used in any medical field, such as for example dental implantology, maxillofacial implantology, orthopedic implantology.

STATE OF THE ART The "primary" stabilization of an implant in a bone structure corresponds to the initial mechanical fixation of this implant to the bone structure, generally in a cavity formed in the bone structure and intended to receive the implant. The primary stabilization is followed by so-called "secondary" stabilization obtained spontaneously and naturally during bone healing at the level of the contact zone between the endosseous surface of the housing prepared in the recipient bone site and the endosseous part of the bone. the implant, but on the condition however to respect on the one hand a rigorous surgical protocol of preparation of the receiving bone site and implant placement and on the other hand that the implants placed in the receiving bone site are in conformity with the standards required, particularly in terms of biocompatibility, traceability, sterilization. This bone proliferation in close contact with the implant, previously immobilized by primary stabilization, is called osseointegration. In addition to gluing, there are two main techniques for primary stabilization of an implant in a recipient bone site. Stabilization can indeed be performed by impaction of the implant in the cavity formed in the recipient bone site, or by screwing the implant into this cavity. Generally the cavity is prepared before implant placement, digging (for example by drilling) and removing a certain bone volume.

In the case of impacted implants, orthopedics, maxillofacial surgery or dentistry, for example, a receiving bone cavity is prepared with a volume of dimensions slightly smaller than the dimensions of the implant. The implant is then inserted by force into the prepared bone cavity, by applying a force in the direction of insertion of the implant into the recipient bone site with suitable "mass" type medical instruments, allowing impaction of the implant. the implant in the bone structure and therefore a primary stabilization.

In the case of screwed implants, primary stability is ensured by screwing the implant into a bone housing slightly smaller than the size of the implant used. More specifically, the threading which is provided on the main body of the implant allows an engagement and an anchoring of the implant in the bone structure by rotation of the implant several revolutions around its longitudinal axis. Screwing can be done by manual screwing or by mechanical screwing (for example using a surgical motor), possibly with a suitable ancillary. Impacted implants and screwed implants have their own particular advantages and disadvantages in terms of placement, but also in terms of effectiveness of primary stabilization. Thus, while screwed implants generally provide more effective primary stabilization, they can not be used for any type of bone. In fact, screw-retained implants are rather indicated in fairly corticalized bones (type I or II) whereas impacted implants are preferred in softer bones (type III or IV).

To overcome this drawback, self-tapping implants have been developed, that is to say having a body having the thread of a self-tapping screw, which makes it possible to anchor the implant in any type of bone structure. without prior preparation of the recipient bone site since it is the screws themselves that create this site. Such implant structures allow the implant to be in intimate contact with the bone structure, even in the case of softer bones. However, just like other types of implants, such self-tapping implants have disadvantages in their implementation. In particular, it can be very difficult to precisely position these implants, both in terms of angular positioning and depth of insertion of the implant.

Other types of implants have also been proposed without these actually solve the aforementioned drawbacks. For example, it has been proposed in Patent Application FR 2,732,890, published on October 18, 1996, an impacted-type implant comprising an elongated body comprising a main section having a relief wall, preferably soft corrugations, and a pointed end. provided with an attachment thread in the bone tissue. Such an implant allowed to have a better primary stabilization than purely impacted implants thanks to its threaded end, while being able to be used in so-called soft bones. However, such an arrangement still does not meet the need for precision in the positioning of the implant, both in angle and depth.

An object of the present invention is therefore to provide an endosseous implant device for solving at least one of the aforementioned drawbacks.

More specifically, an object of the present invention is to provide an implant device of simple design, and therefore the establishment is easy and possible in any type of bone structure. Yet another object of the present invention is to provide an endosseous implant device which can be easily positioned with increased accuracy over existing implant devices, while being simple for the practitioner to implement. SUMMARY OF THE INVENTION To this end, an endo-osseous implant device is proposed for insertion into a housing formed in a bone structure and to be engaged with the bone structure by rotation, characterized in that comprises: - a longitudinal body, preferably of substantially cylindrical or cylindro-conical shape, having a longitudinal axis and extending between a first end and a second end; a positioning head arranged at the first end and forming a shoulder with respect to the longitudinal body, the positioning head having a wall comprising protruding support elements, said support elements enabling the implant device to to bear on the bone structure after insertion of the implant into the housing; - At least one anchoring member projecting from the outer surface of the longitudinal body, said anchor member extending at least partially between the first end and the second end of the longitudinal body; in which said anchoring member has a profile ensuring, during a rotation of the implant device about the longitudinal axis in a fraction of a turn lower than the inverse of the number of anchoring members, a setting direct connection with the bone structure and a translation of the longitudinal body for complementary engagement of the bone structure with the bearing elements of the positioning head.

Preferred but non-limiting aspects of this implant device, taken alone or in combination, are the following: the implant device comprises at least two anchoring members, the anchoring members being arranged so that the device implant has a general symmetry with respect to the longitudinal axis. - The implant device comprises three anchoring members being positioned to form two by two at an angle of 60 ° with respect to the longitudinal axis. the implant device comprises four anchoring members arranged in two pairs of anchoring members, the two pairs of anchoring members being symmetrical to one another with respect to the longitudinal axis, and the two anchoring members of each pair forming an angle less than 900 relative to the longitudinal axis, and preferably less than 60 °. each anchoring member comprises a leading portion having a shape allowing the insertion of the anchoring member into the bone structure during rotation, and an engaging portion dimensioned to ensure both the setting in direct contact and the translation of the longitudinal body during rotation. each anchoring member comprises a plurality of fins, each fin having a non-zero inclination with respect to the longitudinal axis, the inclination preferably being less than 10%, and the inclination being more preferably lower or equal to 2%. each anchoring member comprises a portion of a cylinder or partial truncated cone provided with a thread. each portion of cylinder or partial frustum of cone with a radius of curvature of between 0.5 mm and 3 mm. - The support elements of the positioning head are formed by the roughness of the corresponding wall, or are teeth or micro-grooves formed on said wall. - The positioning head has a side wall substantially parallel to the longitudinal axis comprising teeth or a lateral microgroove protruding radially relative to the longitudinal axis. - The positioning head further comprises a portion having a smooth side wall, the smooth wall being curved towards the longitudinal axis. - The longitudinal body has walls in which are formed blind holes so as to form honeycomb walls. - The longitudinal body has walls in which is provided at least one blind groove at each anchoring member so as to recover bone fragments extracted from the bone structure during rotation of the implant device. - The longitudinal body comprises at least one through opening between an orifice formed at the first end and at least one opening in a wall of the longitudinal body extending between the first and the second end. - The implant device comprises at least two removable parts provided to fit into one another, the first of the two parts comprising the longitudinal body, and the second of the two parts comprising the anchoring members. the implant device is provided for the dental field, and comprises, at the first end, means for receiving prosthesis fixation elements. According to another aspect of the invention, there is provided a template for the placement of the proposed implant device, comprising an anchor rod having a longitudinal axis adapted to correspond with the longitudinal axis of the implant device, and a guide portion forming a shoulder relative to the anchor rod, the guide portion comprising a number of drilling orifices at least equal to the number of anchoring members of the implant device.

DESCRIPTION OF THE FIGURES Other features and advantages of the invention will become apparent from the description which follows, which is purely illustrative and not limiting and should be read with reference to the accompanying drawings, in which: FIG. 1 is a perspective view an implant device according to a first embodiment of the invention, usable in particular for the dental field; FIG. 2 is a front view of the implant of FIG. 1 along the direction A; FIG. 3 is a front view of the implant of FIG. 1 along the direction B; FIG. 4 is a sectional view of the implant of FIG. 1 along a plane of direction A and parallel to the longitudinal axis L of the implant of FIG. 1; FIG. 4a is a view showing a magnification of the area C of FIG. 4; FIG. 5 is a view from above of the implant of FIG. 1; FIG. 6 is a view from below of the implant of FIG. 1; FIG. 7a is a perspective view of an implant device according to a second embodiment of the invention, usable in particular for the dental field; Figure 7b is a bottom view of the implant of Figure 7a; FIG. 8a is a perspective view of an implant device according to a third embodiment of the invention, usable in particular for the dental field; Figure 8b is another perspective view of the implant of Figure 8a; Figure 8c is a bottom view of the implant of Figure 8a; FIG. 9a is a perspective view of an implant device according to a fourth embodiment of the invention; Figure 9b is a bottom view of the implant of Figure 9a; FIG. 9c is a view from above of the implant of FIG. 9a; Figure 9d is a side view of the implant of Figure 9a; FIG. 9e is a sectional view of the implant of FIG. 9a; FIG. 10a is a perspective view of an implant device according to a fifth embodiment of the invention; Figure 10b is a bottom view of the implant of Figure 10a; FIG. 10c is a view from above of the implant of FIG. 10a; Figure 10d is a side view of the implant of Figure 10a; FIG. 10e is a sectional view of the implant of FIG. 10a; FIG. 11a is a perspective view of an implant device according to a sixth embodiment of the invention; Figure 11b is a bottom view of the implant of Figure 11a; Figure 11c is a top view of the implant of Figure 11a; Figure 11d is a side view of the implant of Figure 11a; Figure 11e is a sectional view of the implant of Figure 11a; FIG. 12a is a perspective view of an implant device according to a seventh embodiment of the invention; Figure 12b is a bottom view of the implant of Figure 12a; FIG. 12c is a view from above of the implant of FIG. 12a; Figure 12d is a side view of the implant of Figure 12a; FIG. 12e is a sectional view of the implant of FIG. 12a; FIG. 13a is a perspective view of a jig device making it possible to form the bone housing for the implantation of the implant illustrated in FIG. 1; FIG. 13b is a front view of the template of FIG. 13a; Fig. 13c is a side view of the template of Fig. 13a; - Figure 13d is a top view of the template of Figure 13a; - Figure 13e is a top view of the template of Figure 13a; FIG. 14 illustrates the successive steps for the preparation and the placement in a bone structure of the implant illustrated in FIG.

DETAILED DESCRIPTION OF THE INVENTION The following description is mainly made with regard to an implant in the dental field. The corresponding teaching may however be adapted for any other implant device having similar structural characteristics, and used in the medical field, in particular for implants relating to maxillofacial surgery, neurology, orthopedics, oto -rhino-laryngology, etc. More generally, the teaching that follows from the description that follows could be adapted to any device intended to be implanted in the human or animal body. The proposed endosseous implant device is intended to be inserted into a housing formed in a bone structure and to be engaged with the bone structure by rotation for what is known as stability - or stabilization - primary. Specifically, the engagement and anchoring of the implant with the bone structure is performed by a very small rotation of the implant on itself since it is done in less than a turn as we will see more far. The general shape of the implant proposed is therefore adapted to allow easy insertion of the implant into a more or less complex housing that has been previously formed in the bone implantation structure. In addition, the implant has a shape that also allows a partial rotation of said implant on itself. As shown in Figure 1, the proposed implant device comprises a main body 10 extending along a longitudinal axis L, called the longitudinal body.

To facilitate both insertion and rotation, the longitudinal body 10 may have a general shape having substantially a symmetry of revolution about the longitudinal axis L. Preferably but not limited to, this longitudinal body 10 has a substantially cylindrical or cylindrical shape -conical. The main body 10 may be elongated as shown in FIGS. 1, 7a and 8a, or have a more flattened shape, for example having the shape of a puck, as shown in FIGS. 9a, 10a, 11a, and 12a. . The longitudinal body may for example have a Morse taper shape, for example with an angle of the order of 5 °. Such a shape facilitates the impaction step during which the implant is inserted into the bone housing. This particular shape makes it possible to guarantee contact between the implant and the walls of the bone structure during impaction and screwing. The longitudinal body 10 may have walls that are smooth, but it is preferable that they have a slight roughness to allow better bone proliferation of the bone wall in contact with this wall. These walls of the longitudinal body 10 can be flat as shown in Figures 1 to 4, but they could also have a slight undulation to also promote bone proliferation. According to another possible embodiment, the longitudinal body 10 has walls in which are formed blind holes or blind cavities, again to facilitate bone proliferation. For example, a plurality of small blind holes may be provided to form honeycomb walls.

Alternatively or additionally, the longitudinal body comprises, as shown in FIGS. 1 and 2, longitudinal blind grooves, arranged along the longitudinal axis L of the longitudinal body 10. These grooves also facilitate bone proliferation. They can also be provided to recover bone fragments resulting from the penetration of the implant into the bone structure. Furthermore, the implant comprises a positioning head 20 arranged at one of the ends of the longitudinal body 10, namely at the end intended to be flush or protruding with respect to the average surface of the structure bone in which the implant is inserted.

This positioning head 20 has substantially the shape of a collar, or other specific shape creating a shoulder relative to the longitudinal body 10. Preferably, the positioning head 20 has a wall comprising bearing elements projecting from the average surface of this wall, the wall in question being preferably the lower wall, that is to say the wall adjacent the longitudinal body 10 intended to be in contact with the hollow wall of the bone structure. These support elements are provided to allow the implant to bear on the bone structure after insertion of the implant into the housing, without this implant comes into contact with the bony walls at the bottom of the housing formed in the housing. bone cavity.

In a preferred but nonlimiting manner, once the implant has been inserted / impacted in the bone housing, but before the screwing of said implant, these support elements constitute the only portions of the implant in contact with the bone structure. These support elements may for example maintain a distance of less than 1 mm, and more preferably less than 0.5 mm, between the average surface of the implant and the walls of the housing of the bone structure. According to one possible embodiment, such bearing elements are, for example, micro-grooves 21 formed on the wall of the positioning head 20 as illustrated in FIG. 4a. These bearing elements may also be teeth or pins formed on the surface of this wall. They may also be constituted by the roughness of the surface of the corresponding wall if it is large enough to form a support preventing contact of the other portions of the implant with the bone structure. Depending on the end use of the implant, the positioning head 20 may be more or less protruding from the outer surface of the bone structure. Preferably, the positioning head 20 is partially buried in the bone structure. The housing formed in this bone structure will in this case preferably have a profile having a peripheral ring, forming a shoulder complementary to the shoulder formed by the positioning head 20. In this respect, it will be possible to use an ancillary device specifically adapted to form the surface. receiving the shoulder 20. This ensures a level of precision allowing both a slight congruence between the bone and the implant during the impaction of the implant, congruence that will be increased by the rotation the implant that will tend to progress (very slightly) into the recipient bone site will be both stabilized by bone anchoring and friction of the cone of the implant with the bone cone, all establishing primary stabilization. It may furthermore, in a non-mandatory manner, be provided on the positioning head 20 a coupling member 40 of the implant with another element.

First of all, this coupling member may for example be used to put the implant in rotation necessary for the engagement of the implant with the bone structure. In this respect, the coupling member 40 may for example have an external profile 41 of hexagonal shape or the like. The coupling member may also make it possible to fix on the implant a superstructure, for example when the implant is intended to be used in the dental field. For example, it is possible to provide means 42 for receiving prosthesis fixation elements, in particular with an internal cavity having a thread. The implant further comprises at least one anchoring member 30 which is shaped to protrude from the side walls of the longitudinal body 10. It is understood that the anchor member does not cover all the walls Lateral longitudinal body 10. The principle of the proposed implant is indeed that it comprises a part of the walls which is unchanged, and a part of the walls where the anchor or members protrude from the wall. Preferably, the implant comprises at least two anchoring members 30 arranged symmetrically with respect to the longitudinal axis L. The fact of having at least two anchor members 30, furthermore symmetrically arranged, gives the implant a substantially symmetrical shape thus facilitating its implantation in the bone structure. The embodiment illustrated in FIGS. 1, 2, 3 and 4 corresponds to an implant configuration with two anchoring members 30 arranged facing one another with respect to the longitudinal axis L. Each organ anchoring 30 preferably extends substantially in a direction parallel to the longitudinal axis L, and it extends at least partially between the two end ends of the longitudinal body 10. Preferably, each anchoring member 30 s extends over the entire length of the longitudinal body 10 to maximize the anchoring points with the bone wall.

The anchoring members 30 are provided, and in particular have a profile and dimensions provided for this purpose, to ensure a direct engagement with the bone structure during a weak rotation of the implant device around the longitudinal axis more precisely, a rotation according to a lower number of turns than the inverse of the number of anchoring members 30 of the implant. We can speak of a fraction of a turn lower than the number of anchoring members 30 of the implant. This direct engagement is the main anchor of the implant in the bone structure. The anchoring members 30 also preferably have a profile and dimensions allowing during this low amplitude rotation a translation of the longitudinal body 20 tending to drive the implant into the bone housing. This translation allows complementary engagement of the implant with the bone structure, in particular at the level of the bearing elements of the positioning head 20. The specific profile of the support elements allows them to sink into the bone structure and ensure a complementary anchorage. The translation also makes it possible to put all the walls of the implant, in particular the walls of the longitudinal body 20, in close contact with the internal walls of the bone housing. Preferably, the rotation may even be such as to allow slight engagement, i.e., insertion, of the implant walls into the walls of the bone housing.

The principle of placing the proposed implant, which will be explained in more detail later, therefore consists in inserting the implant in a housing formed in a bone structure, this housing having a shape complementary to the external shape of the implant. implant, particularly at the longitudinal body 10 and anchoring members 30. The support elements of the positioning head 20 allow to maintain a distance between the implant and the walls of the bone housing after this first step of impaction. Once the implant has been inserted in this housing, it should be screwed partially, applying a very small amplitude of rotation that will be sufficient to anchor the implant in the bone wall while putting in close contact implant and bone structure.

As indicated above, the implant is intended to be engaged via the anchoring members 30 by a low amplitude rotation, preferably at a fraction of a turn lower than the inverse of the number of anchors 30 of the implant, and more preferably in a fraction of a turn less than half the inverse of the number of anchoring members 30 of the implant.

For example, the implant illustrated in FIGS. 1 to 6 comprises two anchoring members and is adapted to be engaged with the bone wall in less than half a turn, preferably in a quarter of a turn.

The fact of having to apply a rotation of very small amplitude makes it possible to increase the precision of placement of the implant. Indeed, it is possible to accurately predict the final positioning of the implant even before the engagement step, since the rotation required for this engagement is very small.

Preferably, each anchoring member 30 comprises a leading portion 31 having a shape allowing the insertion of the anchoring member in the bone structure during rotation. This leading portion 31 may for example have a cutting edge facilitating insertion into the bone structure during the partial rotation. Each anchoring member 30 also preferably comprises a portion 32 sized to ensure both the direct engagement and the translation of the longitudinal body 10 during rotation. For example, this engagement portion 32 may have the shape of a radially projecting edge with respect to the longitudinal axis L, and preferably having a non-zero inclination with respect to the longitudinal axis L makes it possible to induce the depressing effect of the implant during the partial rotation of this implant.

For example, each anchoring member 30 may comprise a portion of a cylinder or partial frustum of cone having an axis parallel to the longitudinal axis L of the longitudinal body 10. To ensure the engagement during the partial rotation of the implant this part of the cylinder or partial truncated cone is provided with a thread. According to another example, as illustrated in Figures 1 to 4, each anchoring member 30 comprises a plurality of fins (30a, 30b, 30c, 30d) arranged relative to each other along the longitudinal axis L. Each fin (30a, 30b, 30c, 30d) further has a leading portion 31 and an engaging portion 32 perpendicular to the longitudinal axis L. As illustrated, the leading portion 31 is preferably a radial projecting edge relative to the longitudinal axis L, which makes it possible to attack the bone without splitting it. Preferably each fin (30a, 30b, 30c, 30d) has an inclination with respect to the longitudinal axis that is not zero and less than 10%, and more preferably of the order of 2% or less than 2%, example of the order of 1%, so as to limit the translation and thus the depression of the implant.

The number of fins (30a, 30b, 30c, 30d) and their dimensioning depends on the shape and dimensions of the implant, more particularly on the longitudinal body 10 of this implant, but also on the hardness of the bone of the housing. . The implant device proposed is generally formed in one piece, that is to say in one piece. However, it may be envisaged to form the proposed implant here from two removable parts provided to fit into one another. In this case, the first of the two parts may for example comprise the longitudinal body 10, and the second of the two parts comprising the anchoring members 30. The positioning head 20 may be integral with the part comprising the elongated body 10, or can even be a third portion to be coupled to the end of the elongated body. Such a multi-part design facilitates the design of the implant, making the machining less complex. Thus, it may for example be envisaged to manufacture the portion having the anchoring members by conventional machining, while the portion comprising the longitudinal body is made of laser fusion, in particular to design the desired surface geometry. The multi-part design can furthermore make it possible to design the different parts of the implant device in different materials. Once the different parts of the implant have been nested, they are secured to each other by any suitable means, for example by hooping or welding. The implant illustrated in FIGS. 1 to 6 corresponds to a dental implant, made of titanium, for example, having a longitudinal body 10 with a length of 10 mm, in a Morse cone shape at an angle of about 5 °, where the diameter at the flange forming the positioning head 20 has a diameter of 4.2 mm, and the lower end of the longitudinal body 10 has a diameter of 2.4 mm. The positioning head 20 has a bottom wall (i.e. the wall towards the longitudinal body 10) substantially perpendicular to the longitudinal body 10, and further having at its periphery an inclined flange. As seen in FIG. 4a, the bearing elements 21 are, in this embodiment, formed on the inclined portion of the bottom wall of the positioning head 20. The bearing element 21 shown is a circular micro-groove whose height is substantially equal to the translation performed by the implant during the fraction of rotation performed for the engagement. The implant configuration presented in these figures comprises four fins (30a, 30b, 30c, 30d) for each of the two anchoring members 30. The overall diameter between two corresponding fins of each of the two anchoring members (see FIG. 6) is 3.8 mm.

In addition, there are as many blind grooves 11 as anchoring members 30, each of these grooves 11 being formed in the longitudinal body 10 each of the leading portions 31 of the fins (30a, 30b, 30c, 30d). In addition to promoting bone proliferation as indicated above, these grooves 11 also make it possible to recover all or part of the bone chips resulting from the penetration of the anchoring members into the bone during rotation of the implant after impaction. The implant which is illustrated in FIGS. 7a and 7b corresponds to an implant identical to that of FIGS. 1 to 6 but comprises three anchoring members 30 instead of two.

These three anchoring members 30 are in this embodiment positioned to form two by two an angle of 60 ° with respect to the longitudinal axis. This configuration reinforces the anchoring of the implant in the bone structure, while gaining precision since the rotation required for anchoring is less than a third of a turn.

The implant which is illustrated in FIGS. 8a, 8b, and 8c corresponds to an implant identical to that of FIGS. 1 to 6 but comprises four anchoring members 30 instead of two. When an implant has four anchoring members 30, they can be arranged relative to each other so that two adjacent anchoring members 30 form two by two an angle of 45 °. These four anchoring members 30 may be arranged in two pairs of anchoring members, the two pairs of anchoring members being symmetrical to one another with respect to the longitudinal axis, and the two members anchoring each pair forming an angle less than 90 ° with respect to the longitudinal axis, and preferably less than 60 °. This configuration with four anchoring members 30 makes it possible to further strengthen the anchoring of the implant in the bone structure, and also improves accuracy since the rotation required for anchoring is less than a quarter of a turn.

FIGS. 9 to 12 illustrate an implant device whose general shape differs from the embodiments already described in that the main body is in the form of a puck, that is to say it has a larger diameter. great as its height. However, it also preferably has a generally cylindrical or cylindro-conical shape. In these figures, the parts of the implant device that have not been modified or little compared with the previous description have kept the same reference numerals. The embodiment shown in FIGS. 9a to 9e corresponds to an implant device in which the longitudinal body 110 has a puck-like shape, slightly cylindroconic. This longitudinal body 110 is formed so as to have a blind internal cavity, open on the side of the positioning head 20. The longitudinal body 110 thus comprises a bottom 112 opposite the opening of the cavity. Preferably, the inner cavity has a large volume, slightly less than the external volume of the longitudinal body 110. However, the walls and the bottom of the longitudinal body 110 have sufficient strength, especially for the impaction and the engagement of the implant by rotation. This cavity could for example be used to house devices or any other element intended to be placed inside the body, in which case it may be possible to place a cover at the positioning head 20 to close the cavity if necessary. . The implant shown comprises five anchoring members 30, which are star-shaped with respect to the longitudinal axis of the longitudinal body 110 so as to maintain the preferred axial symmetry. The anchoring members 30 shown each comprise fins (30a, 30b, 30c) which are arranged to extend between the two ends of the longitudinal body 110. The embodiment shown in FIGS. 10a to 10e corresponds to a device of FIG. implant identical to that in Figures 9a to 9e, but further comprises an opening 113 formed in the bottom 112 of the longitudinal body 110 so that the inner cavity is this time through. Such an implant configuration may for example be used if it is desired to put in communication the two sides of a bone structure. In neurology for example, such an implant device could be positioned through the skull and house an electrical device coupled on the one hand to electrodes in the direction of the brain, and on the other hand to electrical son to be connected to an electrical device external to the patient, for example percutaneously or transcutaneously. The embodiment shown in FIGS. 11a to 11e corresponds to an implant device identical to that in FIGS. 9a to 9e, but also comprises an opening 114 formed in the lateral wall of the longitudinal body 110 so that the internal cavity is through. . The embodiment shown in FIGS. 11a to 11e corresponds to an implant device identical to that in FIGS. 9a to 9e, but also comprises two openings 114 and 115 formed in the lateral wall of the longitudinal body 110 so that the internal cavity is through. Like any impacted implant, it is necessary to prepare the bone structure in a fine way, especially by providing an implant receiving housing having a shape corresponding to the shape of the implant. As is apparent from the foregoing description, the proposed implant device has a particular shape, especially at the elongated body which comprises one or more anchoring members projecting from the outer wall of this elongate body. To facilitate the preparation of the recipient bone site, a template is preferably used which guides the bone drilling, and thus provides a housing having a shape closest to the general external shape of the implant, in particular the part intended for to be buried in the bone structure.

Preferably, the bone housing is made using standard drills used in particular in the field of dental implantology. The diameter of such drills is generally between 1 mm and 6 mm, and preferably use drills of 1.2 mm. For implant configurations having a longitudinal body having a large diameter, larger drills, for example drills of 3.8 mm or 4.5 mm in diameter, may be used. Preferably, a template will be used comprising an anchor rod having a longitudinal axis to correspond with the longitudinal axis of the implant device. Furthermore, the template comprises a guide portion forming a shoulder relative to the anchor rod, this guide portion comprising a number of drilling orifices at least equal to the number of anchoring members of the implant device. . This guide portion is a guide head since it is generally positioned at the end of the anchor rod. Thus, as will be seen later in the description of the procedure for preparing and placing the implant with reference to FIG. 14, the various drilling orifices of the guide head will serve as a guide for the drill, and thus allow to make holes where will be inserted anchors. The guide head may further include other piercing holes for removing bone prior to the final pierce to form the hole corresponding to the diameter of the elongated body of the implant. These complementary piercing holes are particularly useful when the elongate body of the implant has a large diameter, that is, a diameter substantially larger than the diameters of drills used in the surgical field to form holes in the implant. bone. The template which is illustrated in Figures 13a to 13e is adapted to the formation of a bone housing for an implant as illustrated in Figures 1 to 6. This template 200 has a general shape T. The template 200 comprises a portion of An anchor 210, in the form of a rod, which will serve as anchoring to the jig 200 to drill the bone structure. The end of the anchor rod 210, at the head of the T, comprises two tabs (220, 230) extending radially on either side of the longitudinal axis of the rod 210. Each of these tabs ( 220,230) comprises a through hole (221,231) having a diameter corresponding to the drill which is to be used for digging the housing. And T-shaped set therefore serves as a guide to drill accurately the bone structure, in a simple way. As can be seen in FIGS. 13a and 13b, the embodiment of the template 200 proposed has a rod 210 which comprises a longitudinal slot 211 and frustoconical portions 212 forming anchoring teeth 213. As will be seen later, this configuration facilitates insertion into the housing and the anchoring of the template, thanks in particular to the resilience of the material used to form the template. Figure 14 illustrates the different steps for the placement of the proposed implant, including the preliminary stages of preparation of the bone housing for receiving said implant. This procedure is described taking for example the implant illustrated in Figures 1 to 6 and the template of Figures 13a and 13b. The first step El consists in drilling the bone structure in the direction illustrated by the black arrow. This first drilling step is performed for example with a standard dental implantology drill. The hole thus produced will allow to stabilize the template to allow the precise design of the housing for receiving the implant. The second step E2 consists of coming to set up the template in the hole drilled during the first step. To set up this template 200, simply press the two tabs (220,230) of the T to compress the anchor rod 210 at the longitudinal slot 211 to allow the insertion of the template inside. the hole in the bone structure. Once the template 200 has been fully depressed so that the tabs 220,230) abut against the upper surface of the bone structure, the compression applied to these tabs (220,230) is released, the compression applied to these tabs is released. legs (220,230). The resilience of the material used to form the template allows the teeth 213 of the rod 210 of the jig 200 to engage the inner wall of the bone structure. The template 200 is now in place in the bone structure, it can be used to guide the drilling of complementary holes. Thus, in the third step E3, a first hole is drilled through an orifice of one of the two legs of the template. In the fourth step E4, the other hole is drilled using the orifice of the second leg of the jig 200. These first steps made it possible to drill into the bone structure the main holes which will constitute the general shape of the housing. inside which the implant is intended to be positioned. It is therefore possible during the fifth step E5 to remove the template 200, which reveals the three pre-formed holes that are perfectly aligned thanks to the use of the template. During the sixth step E6, the final drilling of the bone structure is carried out which makes it possible to design the definitive shape of the housing intended to receive the implant. As can be seen in Figure 14, the drill used in this drilling step has a substantially larger diameter than previously used drill bits. The drill used in this sixth step E6 has a diameter substantially corresponding to the diameter of the elongated body of the implant to be inserted. For better accuracy, one can for example use a tool type bell saw to do this drilling. Such a tool is constituted by a drill having the diameter of the hole drilled during the first step, arranged coaxially with one or more circular and coaxial cutting elements, the cutting element having the largest diameter corresponding to the diameter of the hole than we are trying to train at this stage. These first six steps therefore make it possible to form a housing whose shape corresponds substantially to the external shape of the implant to be positioned. In particular, the holes that have been formed through the guide holes of the jaws of the jig 200 have made it possible to make the portions of the housing in which the anchoring members of the implant will be able to be inserted without bone contact.

The seventh step E7 corresponds to the insertion of the implant into the housing formed in the bone structure. The implant is inserted into the housing until the positioning head of said implant comes into abutment against the bone structure. As indicated above in the description, it may also be preferred to also provide a shoulder in the bone structure (not shown) substantially corresponding to the shoulder formed by the positioning head of the implant. The eighth step E8 corresponds to the engagement of the implant in the bone structure which is performed by a partial screwing of the implant. It is more accurately a rotation of a fraction of a turn of the implant, for example quarter turn. The illustration of step E9 corresponds to the positioning of the implant when it has been impacted and screwed, that is to say in primary stabilization. The reader will understand that many changes can be made without materially escaping the new lessons and benefits described here. Therefore, all modifications of this type are intended to be incorporated within the scope of the presented implant device.

BIBLIOGRAPHIC REFERENCES - FR 2 732 890

Claims (17)

REVENDICATIONS1. Endo-osseous implant device intended to be inserted into a housing formed in a bone structure and to be brought into engagement with the bone structure by rotation, characterized in that it comprises: a longitudinal body (10), preferably of substantially cylindrical or cylindro-conical shape, having a longitudinal axis (L) and extending between a first end and a second end; a positioning head (20) arranged at the first end and forming a shoulder with respect to the longitudinal body (10), the positioning head (20) having a wall comprising protruding support elements (21), said support members (21) allowing the implant device to bear on the bone structure after insertion of the implant into the housing; at least one anchoring member projecting from the outer surface of the longitudinal body, said anchoring member extending at least partially between the first end and the second end of the body; longitudinal (10); in which said anchoring member (30) has a profile ensuring, during a rotation of the implant device about the longitudinal axis (L) in a fraction of a turn lower than the inverse of the number of organs d anchoring (30), a direct engagement with the bone structure and a translation of the longitudinal body (10) for complementary engagement of the bone structure with the bearing elements (21) of the positioning head (20). 2. Implant device according to claim 1, comprising at least two anchoring members (30), the anchoring members (30) being arranged so that the implant device has a general symmetry with respect to the longitudinal axis (L). 3. Device according to any one of claims 1 or 2, comprising three anchoring members (30) being positioned to form two by two at an angle of 60 ° relative to the longitudinal axis (L). 4. Device according to any one of claims 1 to 3, comprising four anchoring members (30) arranged in two pairs of anchoring members (30), the two pairs of anchoring members (30) being symmetrical to each other with respect to the longitudinal axis (L), and the two anchoring members (30) of each pair forming an angle less than 90 ° with respect to the longitudinal axis (L), and preferably less than 60 °. 5. Implant device according to any one of claims 1 to 4, wherein each anchoring member (30) comprises a leading portion (31) having a shape for insertion of the anchor member. (30) in the bone structure during larotation, and an engaging portion (32) dimensioned to provide both direct engagement and translation of the longitudinal body (10) upon rotation. 6. Device according to any one of claims 1 to 5, wherein each anchoring member (30) comprises a plurality of fins (30a, 30b, 30c, 30d), each fin (30a, 30b, 30c, 30d). ) having a non-zero inclination with respect to the longitudinal axis (L), the inclination preferably being less than 10%, and the inclination being more preferably less than or equal to 2%. 7. Device according to any one of claims 1 to 5, wherein each anchoring member (30) comprises a portion of a cylinder or partial truncated cone provided with a thread. 8. Device according to claim 7, wherein each portion of cylinder or partial frustum of cone with a radius of curvature of between 0.5 mm and 3 mm. 9. Device according to any one of claims 1 to 8, wherein the support elements (21) of the positioning head (20) are formed by the roughness of the corresponding wall, or are teeth or micro-grooves formed on said wall. 10. Device according to any one of claims 1 to 9, wherein the positioning head (20) has a side wall substantially parallel to the longitudinal axis comprising teeth or a lateral micro-groove radially projecting relative to the longitudinal axis (L). 11. Device according to any one of claims 1 to 10, wherein the positioning head (20) further comprises a portion having a smooth side wall, the smooth wall being curved towards the longitudinal axis (L). 12. Device according to any one of claims 1 to 11, wherein the longitudinal body (10) has walls in which are formed blind holes so as to form honeycomb walls. 13. Device according to any one of claims 1 to 12, wherein the longitudinal body (10) has walls in which is formed at least one blind groove (11) at each anchoring member (30) so recovering bone fragments extracted from the bone structure during rotation of the implant device. 14. Device according to any one of claims 1 to 13, wherein the longitudinal body (10) comprises at least one through opening between an orifice formed at the first end and at least one orifice (114,115) formed in a wall. longitudinal body extending between the first and second ends. 15. Device according to any one of claims 1 to 14, comprising at least two removable parts provided to fit into one another, the first of the two parts comprising the longitudinal body, and the second of the two parts comprising the anchors. 16. Implant device according to any one of claims 1 to 15, provided for the dental field, and comprising at the first end means for receiving (40) of prosthesis fasteners. A template for implanting an implant device according to any one of claims 1 to 16, comprising an anchor rod having a longitudinal axis adapted to correspond with the longitudinal axis of the implant device, and a guide portion forming a shoulder relative to the anchor rod, the guide portion comprising a number of piercing orifices at least equal to the number of anchoring members of the implant device.