FR2906709A3 - METHOD OF OBTAINING ENDO-BONE IMPLANT WITH AXIALLY EXTENDED OSTEO-INTEGRATION CLEARANCES - Google Patents

Abstract

The subject of the invention is a process for obtaining an endo-osseous implant. This method consists in providing an axially extended osseointegration relief (7) on a raw body (10), in reducing the raw section S1 of the raw body (10) to a section corresponding to the finished section S2 of a body finished (12), and to arrange at the periphery of the finished body (12) a mechanical fixing relief. The osseointegration relief (7) being formed of a cavity (8), it is formed by piercing from the end face of the raw body (10) and the operation of reducing the gross section S1 of the raw body (10) is operated until a radial outlet of the cavity (8) is obtained on the periphery of the body (1).

Description

1 Process for obtaining an endosseous implant with clearances

  axially extended osteointegration. Technical Field of the Invention

  The invention is in the field of bone surgery and more particularly endosseous implants intended to support a medical device, such as implants used in dental surgery, in reconstructive surgery and / or in ENT surgery ((otolaryngology For example, it relates to a method of manufacturing such an endosseous implant, including osteointegration clearances which are axially extended.

  Endosseous implants are used in surgery to implant a medical device in a patient, such as for example a prosthesis in the dental field. Such implants are likely to be of intra-oral type for use in the dental field in particular, or of the extra-oral type for use in the field of reconstructive surgery and / or ENT surgery, for example. These applications are given by way of example and are not restrictive as to the scope of the present invention. These implants consist of an elongate body which comprises at its air end means for receiving the medical device, and at its end endosseous means for anchoring inside a bone tissue, such as the bone of the jaw for a dental application for example. For a technological environment similar to the present invention, reference may be made to the documents FR2788215 (SABIN et al.), FR2732890 (M. GATE), FR2721197 (RIMIMPLANT) and FR2682283 (SCORTECCI) which describe such endosseous implants.

  There is the problem of the quality of the anchoring of the implant in the bone. The implant is placed inside a housing previously provided in the bone by the practitioner, inside which housing is introduced the endo-bone end of the 2906709 2 body. The anchoring means combine mechanical anchoring means and histological anchoring means. The mechanical anchoring means are in particular of the impaction type and / or of the screw type, which is preferably self-tapping. In general, these mechanical anchoring means implement fixing reliefs which are arranged to hold the implant in position inside the bone when it is put in place. Such fixing reliefs consist for example of a thread and / or annular members such as alternating lips and grooves.

In order to reinforce the mechanical anchoring of the implant and to prohibit the use of its spontaneous removal from the bone, the endo-osseous end of the body is provided with histological anchoring means, which are intended to promote an osteo -Integration of the implant from an exploitation of bone cell development. To this end, it is desired to increase the surfaces of the implant in contact with the bone tissue, in addition to the surfaces already provided by the fixing reliefs. Reliefs specifically dedicated to osseointegration are therefore provided on the endosseous end of the body, to form niches for colonization by bone cells that develop after placement of the implant. These osseointegration reliefs are organized so that any spontaneous removal of the implant is prohibited because of the integration in intimate contact of the endosseous end of the body into the bone mass. Among these osteointegration reliefs, those which extend axially in a direction corresponding mainly to the longitudinal extension of the implant are known. This axial extension corresponds more particularly to an extension of the relief in the axial direction of extension of the implant, that this extension of the relief is coaxial and / or parallel to the median axis of extension of the implant, or that this extension of the relief is slightly inclined with respect to this median axis of an angle less than or equal to 45. For example, the document FR2682283 (SCORTECCI) describes an endo-osseous implant which comprises osteointegration projections shaped in axial clearances, including axial clearances 2906709 3 formed at the periphery of the body of the implant parallel to its median axis, and an axial clearance formed coaxially with the median axis of the body of the implant and opening at the endo-osseous end of the latter. For example again, the document FR2788215 (SABIN et al.) Describes an endosseous implant comprising osteointegration reliefs shaped in axial clearances formed at the periphery of the body of the implant in an inclined manner with respect to its median axis. The structure of the implant must be simple to enable it to be obtained at costs that are not prohibitive for its commercialization. The arrangement and the manufacturing methods of both the fixation reliefs and osseointegration reliefs on the body, must allow an implementation of the implant which is easy and at a lower cost, without affecting the qualities required for these different reliefs. In particular, the arrangement and the methods of realization of the osseointegration reliefs 1.5 must not alter the effectiveness of the fixing reliefs, must take into account the largest possible manufacturing tolerances possible without affecting the quality of the anchoring of the implant in the bone material, and the procedure for the manufacture of the implant must enable it to be obtained with the lowest possible production costs.

Object of the invention The object of the present invention is to propose a process for obtaining an endosseous implant with osteointegration clearances which are axially extended, the implementation of which takes into account all the constraints which have been stated. It is more particularly the object of the present invention to provide such a method of obtaining which makes it possible to manufacture the implant at a lower cost while optimizing the structure of the various anchoring means that it comprises for its reliable and long-lasting implantation in the field. bone material.

The method of the present invention is a method for obtaining an endosseous implant. This endo-osseous implant mainly consists of an axially extended body which comprises at its air end means for receiving a medical device, and at its end endosseous anchoring means 5 inside a bone tissue. These anchoring means comprise at least one mechanical attachment relief formed at the periphery of the body and at least one osteointegration relief which is axially extended. The section of the body is indifferently of polygonal and / or circular shape. More particularly, in the case where the mechanical fixing relief is of the type consisting of a thread, the body is of circular section. In the case where the mechanical fastening relief is of the impaction type consisting for example of annular members such as alternating lips and grooves, the section of the body is indifferently polygonal or circular. The axial extension of the osteointegration relief corresponds more particularly to an extension of the relief in the axial extension direction of the implant, whether this extension of the relief is coaxial and / or parallel to the median axis of the implant. extension of the implant, or that this extension of the relief is slightly inclined relative to this median axis of an angle less than or equal to 45.

The method of the present invention is mainly recognizable in that it consists, from a raw body of gross section S1 greater than a finite section S2 of a finite body, to successively carry out the following operations: *) on the raw body the relief of osseointegration, 25 *) reduce the gross section Si of the raw body to a section corresponding to the finite section S2 of the finite body, *) to arrange at the periphery of the finite body the mechanical fixing relief. The raw section Si and the raw body correspond to the characteristics of a blank from which material is removed for forming the anchoring means and receiving means of a medical apparatus, and for obtaining the finished body of finished section S2 implantable in the bone material.

2906709 5 The formation of the osseointegration relief is performed before any step to obtain the finite section S2 of the finished body and to spare the mechanical fixing reliefs, to preserve the surfaces of the implant used for its implantation in the material. bone and its mechanical maintenance waiting for its osteointegration. This preservation makes it possible to avoid any alteration of the finished body and mechanical anchoring reliefs likely to affect the effectiveness of the positioning and the reliable maintenance of the implant in the bone material prior to its osseointegration.

The accuracy of the radial extension of the osseointegration relief is inexpensively and sufficiently obtained to guarantee the effectiveness of the osteointegration of the implant, while allowing the subsequent obtaining of the finished section. S2 of the finished body and mechanical fixing relief with optimized precision. More precisely, a rigor of dimensional tolerances is only applied for the surfaces necessary for the implant of the implant in the bone material awaiting its osseointegration. The recovery operations of the body are limited: the formation of the relief of Axially extended osteointegration and the reduction of the gross body section 20 can both be made from the same phase of holding the body on a tool, that is to say without removal of the body of this tooling. The method of the present invention is particularly suitable for the formation of an osteointegration relief comprising at least one cavity opening axially to the endo-osseous end of the body. In this case, the cavity is formed by drilling from the end face of the endo-osseous end of the body so that the axis of the cavity is radially offset from the median axis of the body. The operation of reducing the gross section of the raw body is operated until a radial outlet of the cavity is obtained on the periphery of the body, for the formation of a longitudinal window for the passage of bone material to and inside the cavity.

Obtaining at least one osteointegration relief formed of a radially emergent cavity on the body makes it possible to optimize the osteointegration of the implant, while allowing the cavity to be easily formed by piercing from the end face of the endo-osseous end of the body without risk of bursting the blank.

More particularly, the hole formed by drilling is non-emerging on the periphery of the body, and then the window is obtained by reducing the gross section of the body. The precision of the emergent surface of this window at the periphery of the body is obtained easily and at a lower cost, from a reduction of the section of the gross body that can be achieved with imperatives of dimensional tolerances that are not very constraining and easy to implement. artwork. Preferably, a complementary operation consisting in arranging along the axially extended osteointegration relief of the secondary osseointegration reliefs is performed. This complementary operation is performed subsequent to the formation of the axially extended osteointegration relief and prior to the reduction of the gross body raw section to avoid altering the finished body. The secondary osteointegration reliefs are for example formed by micro-grooving, by surface treatment and / or by threading or any other similar technique aimed at forming a succession of radially extending reliefs along the relief of Axially extended osteointegration. For example, the secondary osteointegration reliefs consist of the threads of an internal thread arranged at least partially along the axially extended osteointegration relief. The secondary reliefs of osseointegration are advantageously formed by tapping the cavity prior to the reduction of the gross section of the raw body. Such a tapping operation can be carried out simultaneously with the drilling operation by means of a self-tapping forest, or after the drilling operation by means of a specific tap.

Since the cavity is formed by drilling and finally opens out at the periphery of the finished body, the formation of secondary osseointegration reliefs from an internal thread made in the cavity makes it possible to optimize the osseointegration faculties offered by the implant, while obtaining an easy formation and at a lower cost of these secondary reliefs of osseointegration despite the radial outlet of the cavity along the periphery of the finished body. The formation of secondary osteointegration reliefs is achieved by preserving the mechanical fixation relief and the finished body from any alteration. The outlet of the cavity at the periphery of the body being made during the reduction of the section of the raw body, the tapping of this cavity is easily performed prior to this operation. The secondary reliefs of osseointegration are obtained with low production costs for optimized osteointegration faculties of the implant.

Incidentally, the method comprises an auxiliary operation of bevelling the axial edges of the radial outlet of the cavity. This additional operation is performed after the reduction of the gross body section or even to the formation of the mechanical fixing relief. Such beveling is intended to deburr the edges of the radially open window on the periphery of the finished body, and to provide scraping members of the bone material during the installation of the implant by screwing, to promote the penetration of this material. bone material inside the cavity. The method also includes at least one terminal operation of arranging the receiving means of a medical device on the finished body. This terminal operation comprises, if appropriate, completion of the endocutous end of the body, particularly in the case of an implant placed by impaction, this completion consisting in conferring on the endo-osseous end of the body a shape adapted for a patient. impaction of the implant, such as a rounded conformation or other similar conformation. The terminal operation is performed after the formation of the mechanical fixing relief.

The terminal operation may also comprise a precision operation consisting of providing a junction relief with an adherent surface for receiving a junction relief with an adherent surface complementary to the medical device. Such junction relief with adherent surface is in particular a relief of the Morse taper type or similar relief. The use of such a junction relief for the connection between the implant and a medical device aims to prohibit any movement between the implant and the medical device, or similarly between the implant and an intermediate connecting piece equipping the medical device.

At least one finishing operation is incidentally carried out, and consists of a surface treatment of the endo-osseous end of the body, such as by corrosion and / or sandblasting, or even by a contribution of material by projection in particular. This finishing operation aims to provide micro-reliefs on the treated surfaces to improve the osseointegration of the implant, and is performed after the formation of the mechanical attachment reliefs and if necessary prior to the precision operation for do not affect the adhesion of the junction relief surface. Description of the figures.

The present invention will be better understood on reading the description which will be given of exemplary embodiments, in relation to the figures of the attached plates, in which: FIGS. 1 to 5 are diagrams in axial view illustrating successively respective steps of a method of obtaining an endosseous implant according to a preferred embodiment of the present invention. FIGS. 6 to 9 are illustrations of an end-seen implant at the various stages of the process for obtaining this implant respectively shown in FIGS. 1 to 4.

In FIG. 5, an endo-osseous implant mainly consists of an axially extended body 1 which comprises, at its air end, means 2 for receiving a medical device, and at its end-bone end means anchoring inside a bone tissue. In the exemplary embodiment illustrated, the receiving means 2 combine a threaded hole 3 and a joining surface 4 with an adherent surface of the Morse cone type. The aerial end of the implant 5 also comprises a driving relief 5 of the implant in rotation, as shaped in polygon, for the establishment of the implant in the bone material by screwing. The anchoring means comprise a mechanical fastening relief 6 constituted by an external thread formed at the periphery of the body 1. In the variant embodiment illustrated in FIGS. 4 and 9, the mechanical fastening relief 10 6 is formed peripheral rings for impaction implant placement. The anchoring means also comprise osseointegration protrusions 7 which are axially extended, and which are formed by cavities 8 which open radially on the periphery of the body 1, through a respective longitudinal window 9 for the passage of bone material to and inside the corresponding cavity during implant placement. In Fig.1 and Fig.6, a blank consisting of a gross body 10 rough section SI is placed on a tool for the formation of cavities 8 by drilling. This operation is performed from the end face of the endo20 bone end of the raw body 10, and is preferably completed by a hammering operation to form secondary reliefs 11 of osteointegration consisting of internal threads made in the cavities 8. The cavities 8 are radially offset from the median axis A of the raw body 10, and are formed in full material to preserve the raw body 10 from any risk of bursting. In Fig.2 and Fig.7, the body 10 is machined to reduce its section S1 to a section S2 corresponding to the section of a finite body 12 implantable in the bone material. This operation aims not only to adjust the section S2 of the finished body 12, but also to open the cavities 8 on the periphery of the body to provide the windows 9.

In FIGS. 3 and 8, on the one hand, and in FIGS. 4 and 9, on the other hand, the mechanical fixing relief 6 is formed at the periphery of the finished body 12. beveling the edges of windows 9 is preferably performed. In FIGS. 3 and 8, the mechanical fixing relief 6 consists of an external thread 5 formed at the periphery of the finished body 12. In FIGS. 4 and 9, the mechanical fixing relief 6 is formed of peripheral rings 13 which are formed concomitantly with the reduction of the section SI of the raw body 10 to obtain the finished body 12. In this case, the endo-osseous end 14 is completed by conferring on it a shape promoting the impaction of the implant, such as a rounded shape 10 on the exemplary embodiment illustrated. In Fig.5, the implant is completed by a terminal operation of forming the receiving means 2 of the medical device and optionally the driving relief 5 in rotation of the implant. Incidentally, a finishing operation is performed to perform a surface treatment of the implant promoting its osseointegration. Then a finishing operation is optionally performed to form the junction relief 4 with adherent surface. The method of the present invention makes it possible to obtain at an inexpensive cost an endo-osseous implant that is effective and reliable, in particular by the easy formation of an osteointegration relief 7 the structure of which favors the osteo-integration of the bone. implant. This osseointegration relief 7 is axially extended and is advantageously formed of at least one cavity 8 which is delimited by an inner wall of the body 1 of the implant shaped as a portion of a circle. As illustrated in FIG. 1, this or these cavities 8 are formed by piercing the raw body 10 in full material from the end face of its endo-osseous end 14, to prevent its bursting. As illustrated in FIG. 2, this or these cavities 8 open laterally at the periphery of the finished body 12 through a longitudinal window 9 for the passage of bone material to and inside the cavity or cavities 8. This or these outlets 30 are obtained by a reduction of the section S1 of the raw body 10 for folding the blank to obtain the finished section S2 of the finished body 12.

Claims (9)

claims   1. A method for obtaining an endosseous implant mainly consisting of an axially extended body (1) which comprises at its air end means for receiving (2) a medical device, and at its end endosseous means for anchoring inside a bone tissue, these anchoring means comprising at least one mechanical fixing relief (6) formed at the periphery of the body (1) and at least one osteointegration relief ( 7) which is axially extended, characterized in that it consists of starting from a raw body (10) of gross section SI greater than a finite section S2 of a finite body (12), to carry out successively the following operations: *) arrange on the raw body (10) the osseointegration relief (7), *) reduce the gross section SI of the raw body (10) to a section corresponding to the finite section S2 of the finished body (12), *) at the periphery of the finished body (12) to arrange the mechanical fixing relief.   2. A process for obtaining an endo-osseous implant according to claim 1, the osteointegration relief (7) comprising at least one cavity (8) opening axially to the endo-osseous end of the body (1). ), characterized in that the cavity (8) is formed by drilling from the end face of the endo-osseous end of the body so that the axis of the cavity (8) is radially offset from the median axis A of the body (1), and in that the reduction operation of the raw section SI of the raw body (10) is operated until a radial outlet of the cavity (8) is obtained on the periphery of the body (1) for the formation of a longitudinal window (9) for the passage of bone material to and inside the cavity (8).   3. A process for obtaining an endo-osseous implant according to any one of the preceding claims, characterized in that it comprises the complementary operation consisting of arranging along the osteointegration relief (7) axially extended secondary reliefs (11) osteointegration, this complementary operation being performed after the formation of the osteointegration relief (7) axially extended and prior to the reduction of the gross section S1_ of the gross body (10).   4. A process for obtaining an endosseous implant according to claims 2 and 3, the secondary reliefs (11) of osseointegration being constituted by the threads of an internal thread arranged at least partially along the Axially extended osseointegration relief (7), characterized in that the secondary osteointegration projections (11) are formed by tapping the cavity (8) prior to the reduction of the raw section S1 of the raw body ( 10). 10   5. A method for obtaining an endosseous implant according to any one of claims 1 to 4, characterized in that it comprises the annex operation of beveling the axial edges of the radial outlet of the cavity (8). , this auxiliary operation being performed subsequent to the reduction of the raw section S1 of the raw body (10) and the formation of the mechanical fixing relief (6).   6. A process for obtaining an endosseous implant according to any one of the preceding claims, characterized in that it comprises at least one terminal operation consisting in arranging on the finished body (12) the receiving means. (2) a medical device and if necessary to complete the endo-osseous end (14) of the body (1), this terminal operation being performed after the formation of the mechanical attachment relief (6). 25   7. A process for obtaining an endosseous implant according to claim 6, characterized in that the terminal operation comprises a precision operation of providing a junction relief (4) with an adherent surface for the reception of a junction relief with adherent surface complementary to the medical device. 30   8. A process for obtaining an endosseous implant according to any one of the preceding claims, characterized in that it comprises at least one finishing operation consisting of a surface treatment of the end end. bony body (1), this finishing operation being performed after the formation of the mechanical attachment reliefs (6) and if necessary prior to the precision operation. 5   9. Endo-osseous implant obtained by the implementation of a method of obtaining according to any one of claims 2 to 8, characterized in that the osteointegration relief (7) axially extended is formed of at least one cavity (8) which is delimited by an inner wall of the body (1) of the implant 10 shaped as a circle portion, and which opens laterally at the periphery of the body (1) through a longitudinal window (9) passing the bone material to and inside the cavity (8).