BE1028336B1 - AGENCY COVER DEVICE TO PROMOTE BONE REGENERATION - Google Patents

Abstract

The present invention relates to a covering device arranged to promote bone regeneration of a bone defect site which is obtained by additive manufacturing and which comprises at least one shell formed of a porous matrix, as well as its method of manufacture.

Description

TECHNICAL FIELD The present invention relates to a covering device arranged to promote bone regeneration of a bone defect site. The present invention further relates to a method of manufacturing a bone covering and regeneration device.

The basic principle of bone regeneration lies in the creation of a hematoma under the periosteum, that is to say an accumulation of blood under the connective and fibrous membrane which constitutes the envelope of a bone. When a hematoma under the periosteum is created, bone regeneration begins at the level of the existing bone, the cells colonize the hematoma, the blood clot, up to the barrier represented by the periosteum.

It is therefore understood that the essential step in bone regeneration, during a surgical intervention, is the detachment of the periosteum of at least part of the bone to be regenerated, making it possible to create a cavity, a confined chamber, filled with the blood clot and in which bone regeneration will take place.

In the field of bone regeneration, for example dental or related to the functioning of the masticatory apparatus, the main objective is to be able to anchor a dental implant directly in the patient's bone which makes it possible to support one or more tooth(s). ) artificial(s), generally ceramic, whether in the context of reconstructive surgery or cosmetic surgery.

Dental implants look like a screw, provided or not with a certain base which occupies a certain volume and it is necessary that this dental implant be firmly anchored in the jaw and consequently that enough bone is present for the anchorage be efficient.

However, all too often, the patient's bone is not sufficient to anchor the dental implants and bone reconstruction is necessary.

Bone reconstruction techniques are different, in fact the bone can be missing in height, thickness and the locations as well as the related requirements are also different. One could cite by way of example that bone regeneration is more difficult at the level of the mandible than at the level of the upper jaw because the blood flow is weaker. In the context of dental surgery, it may be necessary to regenerate a missing part of the patient's bone in order to anchor a dental implant to it later. It is therefore necessary to carry out a stage of bone regeneration of the patient's missing bone.

A first known technique is the use of a resorbable membrane and a biomaterial for filling the bone regeneration space. Indeed, during the incision and the detachment of the periosteum, this one is cut, damaged and can be subject to preliminary infectious problems, it is therefore necessary to use a resorbable membrane, for example in collagen, which makes it possible to play the role of the periosteum in order to create the bone regeneration chamber, under the soft tissues, for example the mucous membrane. However, when the resorbable membrane is moistened or soaked with blood, it becomes soft and collapses on the bone defect to be regenerated, which is undesirable. A biomaterial, enabling bone regeneration, is therefore used to fill the bone regeneration space and support the resorbable membrane. The resorbable membrane is also a barrier preventing the penetration of soft tissues inside the cavity and therefore into the blood clot.

Biomaterials make it possible to replace bone grafts and dispense with the use of the patient's autologous bone, they can be of different natures such as, for example, allogeneic if they come from other human beings donors or even from a bank of 'bones, or xenogenes if they come from animals.

However, with this first technique, it is easy to use biomaterials, for example in the form of particles, but it is not easy to maintain the desired bone volume. Indeed this first technique generally leads to bone regeneration with the creation of a very sharp bone ridge top which will not have the necessary width and which will therefore not be possible to implant with a dental implant later.

In addition, for a dental implant to be corectly and solidly anchored to the patient's bone, it must be osseointegrated therein, that is to say that a weld be made by the bone. living of the patient on the surface of the dental implant. This requires that the dental implant can properly penetrate the patient's living bone, which must be wide enough for osseointegration to take place.

Additionally, if the dental implant cannot be properly osseointegrated once implanted, scar tissue may form and an inflammatory reaction may also occur around the dental implants, creating a fibrous encapsulation isolating the dental implant from the dental implant. bone and further accentuating the degradation problems that can occur in the long term, generally requiring a new surgery, which is not desirable for the patients.

A second known technique is the use of a metal frame intended to support the resorbable membrane and which makes it possible to support the desired volume below which the biomaterial allowing bone regeneration will be placed, as cited for example in document EP3568166. However, although this metal framework makes it possible to support the desired bone volume, a second surgical act is necessary to carry out the removal of the metal framework.

This second act is just as invasive as the first surgical act, which is to be avoided for patients.

A third known technique is the use of very thin plates of autologous bone from the patient taken locally and which are arranged so as to create the shell in which the biomaterial is placed for bone regeneration.

However, although it is not necessary to remove the autologous bone plates from the patient because these can be integrated correctly into the new bone regeneration site, there remains a drawback, in particular in the prior removal of these bone plates. autologous bone resulting in two surgeries at two different patient sites, which is undesirable.

Another disadvantage is that these autologous bone plates of the patient are pieces of bone already formed and therefore very dense, this does not allow good circulation of living cells to achieve the osseointegration of the dental implant which will be anchored later.

A fourth known technique has been developed in order to avoid the harvesting of autologous bone from the patient, in this one, the bone material Used, to create the shell in which the biomaterial will be placed, is of xenogenic or allogenic origin coming from 5 example of a bone bank.

However, although this technique has many advantages, several disadvantages persist. Indeed, the pieces of xenogenic or allogenic bone must be cut out as needed, which requires a considerable amount of time. This is difficult, imprecise and very dependent on the technical skill of the practitioner. In addition, this technique is not very reproducible and once the bone plates have been trimmed, it is necessary to fix them using screws to the patient's adjacent bone, requiring a subsequent operation for the removal of the screws. Another persistent disadvantage is the weak osseointegration of these shells of xenogenic or allogenic origin, in fact, it is actually non-living bone, partly necrotic, therefore on the one hand no longer comprising living cells. to allow correct osseointegration of the subsequently implanted dental implant and on the other hand in the case of already formed and very dense bone, not allowing the circulation of adjacent living cells in these xenogenic or allogenic bone shells.

There is therefore a need to be able to work to measure in order to provide a covering device arranged to promote bone regeneration of a bone defect site which is easy to use, quick to manufacture, reproducible, of dimensions adapted to the bone defect. of the patient and which is independent of the technicality of the practitioner.

The prior art Document WO2016/180397 is known from the state of the art, which proposes to solve these drawbacks and discloses a device for covering a bone defect site which is formed from a cap corresponding to the regenerated bone and at least one fixing means arranged in the bone site to be regenerated in order to fix the cap to the patient's bone. This fixing means being for example a pin, a screw, a nail or even a bone adhesive.

Although this document contributes to the improvement of devices for covering a bone defect site, unfortunately it turns out that several disadvantages persist.

In fact, the devices for covering a site of a bone defect must make it possible, on the one hand, to resist the forces of mastication in order to maintain the desired bone volume so that the regenerated bone is able to be subsequently implanted by a dental implant. The covering devices must also be easy to use for the practitioner by avoiding manual steps which are a source of inaccuracy and very dependent on the technical skill of each practitioner. Finally, the devices must allow bone regeneration of the bone defect while avoiding the multiplication of surgical acts for patients which are invasive, sources of discomfort and multiplying post-operative complications.

Brief Summary of the Invention The object of the invention is to provide a covering device arranged to promote bone regeneration of a bone defect site which overcomes the drawbacks of the devices of the prior art.

To solve this problem, provision is made according to the invention for a covering device arranged to promote bone regeneration of a bone defect site provided with a bone surface, said device being obtained by additive manufacturing and comprising at least one shell formed a porous matrix which comprises a first inner face facing said bone defect site and a second outer face opposite said first face characterized in that the porous matrix extends at least partially between said first and second faces and has a series of pores of size between 50 and 1000 μm and in that the device comprises at least one support pillar comprising a series of first end(s) bonded to said first internal face of the shell and a series of second end(s) opposite said bonded first end and arranged to rest on said bony surface of the bone defect site, said device being made of ceramic than synthetic and arranged to delimit a cavity arranged to house a volume of bone to be regenerated and optionally to receive at least one bone regeneration material.

The covering device arranged to promote bone regeneration according to the present invention particularly advantageously comprises at least one shell formed of a porous matrix, this makes it possible to maintain the bone volume to be regenerated.

Indeed, the porous matrix comprises a first inner face which faces the bone surface of the bone defect site and a second outer face opposite the first inner face.

Thus, the bone volume to be regenerated is maintained between the bone surface of the patient's bone and the first inner face of the porous matrix of the device according to the invention.

During the surgical operation, after the positioning of the covering device arranged to promote bone regeneration according to the invention, a resorbable membrane can be deposited on the second external face in order to create a barrier preventing the penetration of soft tissues to the interior of the cavity.

In addition, the covering device arranged to promote bone regeneration according to the present invention is arranged to receive at least one bone regeneration material, for example as cited in document EP3568166 or in document EP30521 54.

In a particularly advantageous manner, the porous matrix of the shell of the device according to the invention comprises a series of pores of size between 50 and 1000 μm, this has the advantage of allowing revascularization, colonization of bone cells and therefore regeneration. bone within the porous matrix of the shell of the device according to the invention.

Thus, the device according to the present invention advantageously allows regeneration to begin at the level of the bone surface of the patient's bone, to continue in the bone regeneration material used to fill the bone defect or in the blood clot formed in the cavity, and continues into the porous matrix of the device according to the invention.

After bone regeneration, we therefore obtain a bone regenerated by living cells which has an optimal shape and size to be able to implant a dental implant and this dental implant will be able to osteo-integrate correctly with the new bone since a weld can be carried out by the cells of the living bone of the patient on the surface of the dental implant.

The covering device arranged to promote bone regeneration according to the present invention particularly advantageously comprises at least one support pillar which comprises a series of first end(s) bonded to the first inner face of the matrix shell and a series of bonded second end(s) arranged to rest on the bony face of the bony defect site. This has the advantage of providing a cover device arranged to promote bone regeneration according to the present invention which on the one hand will remain in place to maintain the desired bone volume and on the other hand resist the chewing forces.

Against all expectation, it turned out that said at least one support pillar of the device according to the present invention makes it possible to dispense with an invasive fixing means such as a screw, a clip, a hook or the like.

Indeed, the device according to the present invention makes it possible, on the one hand, to promote the colonization of the cavity by living bone cells, thus making it possible to promote bone regeneration in the shell using the blood clot formed or the bone regeneration material. received in the cavity, and on the other hand when a dental implant is subsequently implanted, it is advantageously implanted in a living regenerated bone thus allowing its osseointegration.

Finally, dispensing with the use of an invasive fixing means, the device according to the present invention does not require a second surgical operation in order to remove any screws, staples, hooks or other invasive fixing means as presented. in the prior art, thereby decreasing the risk of patient inconvenience, complications and morbidity.

Furthermore, by having a device according to the present invention, which comprises at least one support pillar in order to rest on the bone defect site to be regenerated and possibly being arranged to receive at least one bone regeneration material in the volume bone to be regenerated and for example to receive a resorbable membrane on the second outer face of the porous matrix, a device is available which can be adapted to each bone defect to be regenerated in patients given that it is made to measure by process of additive manufacturing and in addition a device is provided which remains firmly in place in the site of the bone defect, which allows bone regeneration in an optimal manner in the site, in the cavity and into the porous matrix, which resists the forces mastication and in a particularly advantageous manner which does not require subsequent surgical operations since the device according to the invention is integrated during the regulation bone generation, does not need to be removed, dispenses with an invasive means of fixation and allows osteo-integration of a subsequent dental implant.

Since the device according to the present invention is made of synthetic ceramic, it can be made of resorbable synthetic ceramic, for example tricalcium phosphate, which allows the device according to the invention to be gradually degraded and replaced by regenerated bone or else, it may be made of non-absorbable synthetic ceramic, for example hydroxyapatite, which allows the device according to the invention to retain its properties over time and to remain in place. In these two cases, the device according to the invention remains in place following the first surgical operation and does not need to be removed subsequently, which is particularly advantageous for the patients.

The dependent claims refer to further advantageous embodiments.

In one embodiment of the covering device arranged to promote bone regeneration according to the invention, the shell has a U-shaped cross-section comprising a main wall from which two side walls extend in a substantially transverse direction, said main wall being provided with said first and second faces and formed from said porous matrix.

More particularly, a first side wall of the two side walls extending from the main wall is a buccal side side wall and a second side wall of the two side walls extending from the main wall is a lingual side side wall.

In one embodiment of the covering device arranged to promote bone regeneration according to the invention, the side walls each have an inner face and an outer face between which they extend and are formed of said porous matrix.

In another embodiment of the covering device arranged to promote bone regeneration according to the invention, the shell has an L-shaped cross section comprising a main wall from which a side wall extends in a substantially transverse direction, said main wall being provided with said first and second faces and formed from said porous matrix.

More particularly, the side wall extending from the main wall is a side wall on the buccal side or is a side wall on the lingual side.

Advantageously, the side wall extending from the main wall of the hull having an L-shaped cross section has an inner face and an outer face between which they extend and are formed of said porous matrix.

This has the advantage that, the inner faces of the side walls and of the main wall delimit the cavity of the bone defect to be regenerated, the outer faces of the side walls and of the main wall are arranged to be exposed to the oral environment during surgical operation or even advantageously arranged to receive a resorbable membrane. In addition, the main and side walls can be solid, that is to say formed entirely of the porous matrix, or can be formed of a discontinuous face, that is to say comprising a series of orifices or arches of porous material.

In one embodiment of the covering device arranged to promote bone regeneration according to the invention, the side walls each have an end linked to said main wall and a free end, arranged to be in contact with a bone material of said bone surface. the bone defect site OR a healthy area adjacent to said bone defect.

In one embodiment of the covering device arranged to promote bone regeneration according to the invention, the pores of said series of pores of the porous matrix have a size of between 100 and 900 μm, preferably between 150 and 850 μm, preferentially between 200 and 800 μm, advantageously between 250 and 750 μm and in a particularly advantageous manner between 300 and 700 μm.

This has the advantage of providing a device in which the porous matrix allows on the one hand bone colonization and regeneration and on the other hand osseointegration which are optimal in the porous matrix. Indeed, the dimensions of the pores of the porous matrix have a size which makes it possible to promote the colonization of the matrix by bone cells and bone tissue, so as to allow the colonizing cells to access the core of the porous matrix. Thus, the colonizing bone cells by gaining access to the heart of the porous matrix, thus make it possible to regenerate a new living bone of the patient, to the heart of the porous matrix. When a dental implant is subsequently implanted, it may not only be osseointegrated by the regenerated patient's bone in the bone defect site but it may also be osseointegrated by the regenerated patient's bone in the porous matrix of the device according to the invention, this therefore creates, after osseointegration of the dental implant, a rigid assembly, resistant over time and able to regenerate over time given that the regenerated bone of the patient is alive.

In one embodiment of the device according to the invention, said at least one support pillar has an average diameter Dm of between 400 and 2000 μm.

In one embodiment of the device according to the invention, said at least one support pillar has a diameter D at all points equal to the average diameter Dm +/- 10%.

This has the advantage of being thin enough to maximize the space available for colonization and therefore for bone regeneration by the bone regeneration material which fills the desired bone volume, while ensuring mechanical strength of the device according to the invention. against the shear and compressive stresses inherent in the functioning of the masticatory apparatus.

In one embodiment of the device according to the invention, said at least one support pillar is of substantially cylindrical shape.

In one embodiment of the device according to the invention, the synthetic ceramic is composed of a material chosen from the group comprising hydroxyapatite, tricalcium phosphate, and their mixture. This has the advantage of providing a device according to the invention composed of tricalcium phosphate which is resorbable and therefore which will be gradually degraded and replaced by regenerated bone. In another embodiment, this has the advantage of providing a device according to the invention composed of hydroxyapatite which is non-absorbable and which will therefore retain its properties over time and remain in place while allowing osteo- integration of a dental implant anchored later. In yet another embodiment, the device according to the invention composed of a mixture of tricalcium phosphate and hydroxyapatite makes it possible to provide a device according to the invention which is at least partially resorbable and which retains its properties over time. The mixture of hydroxyapatite and tricalcium phosphate can be prepared in situ or can be purchased commercially already formed in the form of BCP (“Biphasic Calcium Phosphate”).

In another embodiment, the device according to the invention may comprise at least two support pillars, for example three support pillars, for example four support pillars, for example five support pillars. Indeed, the greater the bone defect, the greater the bone volume to be regenerated, it is therefore advantageous to have a device according to the invention comprising several support pillars in order to provide stability and resistance to the device according to the invention in the upper bone defect.

In one embodiment of the device according to the invention, said at least one support pillar comprises a foot part, a body part and a head part, the foot part being the part arranged to rest on the bone surface of the bone defect site, the head part being the part connected to the first interior face of the shell, the body part being located between said foot part and said head part.

In addition, said at least one support pillar of the device according to the invention extends in a secant direction, that is to say not parallel, the main wall of the shell.

Advantageously, said at least one support pillar of the device according to the invention may comprise a series of ramifications which extend from the foot part and/or from the body part and/or from the head part of said at least one pillar. This advantageously makes it possible to provide additional resistance to the device according to the invention and to resist even better the forces of mastication.

Furthermore, the support pillars of the device according to the present invention can advantageously be interconnected.

In another embodiment of the device according to the invention, each support pillar may comprise at least two first ends bonded to said first interior surface of the shell, for example three first ends bonded to said first interior surface of the shell, for for example four first ends bonded to said first inner surface of the hull, for example five first ends bonded to said first inner surface of the hull, for example six first ends bonded to said first inner surface of the hull.

This makes it possible to provide a device according to the present invention which comprises at least one support pillar which has a second end which rests on the bone surface of the bone defect and which has several first ends linked to the shell.

In one embodiment of the device according to the invention, said porous matrix is a porous matrix at least partially sintered, and/or enriched, in order to reinforce the mechanical resistance of the covering device arranged to promote bone regeneration according to the invention.

In one embodiment of the device according to the invention, the porous matrix comprises a pore volume of between 1 and 50%. In one embodiment, the device according to the invention occupies a maximum volume of 30% relative to the volume of the bone defect to be regenerated, preferably a maximum volume of 25%, more preferably a maximum volume of 20%, and optionally said bone regeneration material received in said cavity is crossed by said at least one support pillar.

In one embodiment of the device according to the invention, the porous matrix comprises a thickness of between 500 and 10,000 μm, preferably between 500 and 7,500 μm, preferentially between 500 and

5000 µm, preferably between 500 and 4000 µm. For example, the porous matrix comprises a thickness of 1 mm, 1.5 mm, 2 mm or even 2.5 mm or 3 mm.

In one embodiment of the device according to the invention, the porous matrix and/or said at least one support pillar has a surface roughness of between 0.70 and 2.10 μm, preferably between 0.80 and 200 μm , preferably between 090 and 190 μm, advantageously between 1.00 and 1.80 μm, particularly advantageously between 1.10 and 1.70 μm.

Other embodiments of the device according to the present invention are mentioned in the appended claims.

The present invention also relates to a method of manufacturing a covering device arranged to promote bone regeneration according to the invention, comprising the steps of a) parametrizing the bone defect to be filled, b) modeling said covering device arranged to promote bone regeneration, c) preparation of said device by additive manufacturing, d) collection of said covering device arranged to promote bone regeneration manufactured after elimination of residues accumulated in the porous matrix during additive manufacturing by blowing, immersion in a liquid.

In a preferred embodiment, the manufacturing method according to the invention further comprises a step of sintering the collected device at a temperature between 1000°C and 1300°C, preferably between 1050°C and 1250°C , preferably between 1100°C and 1200°C.

In another embodiment, said sintering takes place for a period of between 1 and 6 hours, preferably between 2 and 5 hours, preferably between 2 and 4 hours, advantageously for a period of between 2.5 and 3.5 hours. .

In a preferred embodiment, the manufacturing method according to the invention further comprises a step of enrichment of the porous matrix.

Another advantage of the manufacture of the covering device arranged to promote bone regeneration according to the invention by additive manufacturing and that it makes it possible to create a device made to measure and adapted to the patient's bone defect, thus limiting the intervention of the surgeon or the practitioner who is no longer obliged to cut the device before the patient's operation. In addition, additive manufacturing also makes it possible to control the manufacture of the pores of the porous matrix of the shell of the device as well as its thickness and also to control the position, the inclination, the shape or even the number of the support pillars of the device. .

Other embodiments of the method of manufacture are indicated in the appended claims.

Other characteristics, details and advantages of the invention will emerge from the description given below, on a non-limiting basis and with reference to the figures.

Detailed description of an embodiment of the invention FIG. 1 represents a schematic sectional view of the covering device arranged to promote bone regeneration according to the invention.

FIG. 2 represents a schematic sectional view of a skull and more particularly of the mandible on which rests the covering device arranged to promote bone regeneration according to the invention.

FIG. 3 represents a front view of FIG. 2 and more particularly of the mandible on which rests the covering device arranged to promote bone regeneration according to the invention.

In the figures, identical or similar elements bear the same references.

The covering device arranged to promote bone regeneration according to the present invention and illustrated in the figures delimits a cavity, which cavity makes it possible to accommodate a volume of bone to be regenerated and which can optionally receive at least one bone regeneration material. The device according to the invention occupies a maximum volume of 30% relative to the volume of bone to be regenerated of the cavity of the bone defect site, preferably a maximum of 25% and more particularly a maximum of 20%, and this volume of The bone to be regenerated extends from the bone surface of the bone defect site to the shell of the device and more particularly to the second outer face of the shell.

The device according to the invention and as illustrated is particularly obtained by additive manufacturing, which makes it possible to produce a device that is made to measure and adapted to the bone defect of the patient. The device comprises a shell formed of a porous matrix which comprises a first internal face and which faces the bone defect site and a second external face on which can optionally rest a resorbable membrane making it possible to prevent that soft tissues penetrate into the cavity of the bone defect to be regenerated.

More particularly, the porous matrix of the shell extends at least partially between the first and second faces and comprises a series of pores whose size is between 50 and 1000 μm, advantageously between 100 and 900 μm, preferably between 150 and 850 μm, preferentially between 200 and 800 μm, more advantageously between 250 and 750 μm and in a particularly advantageous manner between 300 and 700 μm. As shown in Figures 1 and 2, the device according to the invention comprises at least one support pillar and more particularly the volume of bone to be regenerated in the cavity is crossed by six support pillars as shown in the figure 1 and four supporting pillars as shown in Figure 2.

Each support pillar of the device according to the invention comprises a series of first ends linked to the first interior face of the shell and a series of second ends which rest on the bone surface of the bone defect site. More particularly, each support pillar is of substantially cylindrical shape and has an average diameter Dm of between 400 and 2000 μm and a diameter D at all points equal to the average diameter Dm +/-10%.

Furthermore, and as shown in Figures 1 and 2, each pillar comprises a foot part, a body part and a head part. The foot part being the part arranged to rest on the bone surface of the bone defect site, the head part being the part connected to the first internal face of the shell, the body part being located between said foot part and said head part. Each pillar can also comprise a series of ramifications which extend from the head part of the pillar and which make it possible to provide additional resistance to the device according to the invention. Of course, the series of ramifications of each pillar can also extend from the body part and/or from the foot part and/or from the head part.

The shell of the device according to the invention, which delimits a bone regeneration cavity in which a bone regeneration material can be placed. The shell of the device as shown in FIG. 3 has a U-shaped cross-section comprising an upper wall from which two side walls extend in a substantially transverse direction. The shell of the device as shown in Figures 1 and 2 has an L-shaped cross section comprising an upper wall from which extends a side wall, preferably located on the buccal side and which can also be located on the lingual side of the patient's mouth. . Figures 1 and 2 show a first side wall and part of the top wall, Figure 3 shows a second side wall and the top wall. Each of the side walls and of the upper wall has an inner face and an outer face between which extends the porous matrix of the shell according to the invention. Advantageously, the pores of the series of pores of the porous matrix according to the invention open out, the inner and outer faces of the side and upper walls of the shell therefore have openings corresponding to the pores of the series of pores of the porous matrix.

Each side wall has an end linked to the upper main wall, and a free end which is in contact with the bone surface of the bone defect site or of a healthy zone adjoining the bone defect. Thus, a first bone volume to be regenerated is defined between the bone surface of the bone defect site and the interior walls, for example side and main walls, of the device according to the invention. A second bone volume to be regenerated is defined between the bone surface of the bone defect site and the outer walls, for example side and main walls, of the device according to the invention.

Particularly advantageously, the device according to the present invention enables bone regeneration from the bone surface of the patient's bone in the bone defect site, possibly continuing into the bone regeneration material used to fill the bone defect or into the blood clot formed in the cavity, and continues into the porous matrix of the device according to the invention, preferably to the outer walls of the shell matrix. This advantageously makes it possible to regenerate living bone into the device, thus promoting the implantation of a subsequent dental implant directly into the regenerated bone, without the need to remove the device, and also promoting the osseointegration of the dental implant given that the device according to the invention, more particularly the porous matrix, is colonized by living bone cells which will be able to achieve the osseointegration of the dental implant.

Furthermore, the porous matrix comprises a thickness comprised between 500 and 10000 μm, preferably between 500 and 7500 μm, preferentially between 500 and 5000 μm, advantageously between 500 and 4000 μm. For example, the porous matrix comprises a thickness of 1 mm, 1.5 mm, 2 mm or even 2.5 mm or 3 mm, and a surface roughness of between 0.70 and 2.10 μm, preferably between 0. 80 and 200 μm, preferably between 090 and 190 μm, advantageously between 1.00 and 1.80 μm, particularly advantageously between 1.10 and 1.70 μm.

Preferably, the at least one support pillar has a surface roughness of between 0.70 and 2.10 μm, preferably between 0.80 and 200 μm, preferentially between 090 and 190 μm, advantageously between 1.00 and 1.00 μm. .80 μm, particularly advantageously between 1.10 and 1.70 μm.

Finally, in one embodiment, the device according to the invention is composed of tricalcium phosphate which is resorbable and therefore which will be gradually degraded and replaced by regenerated bone. In another embodiment, the device according to the invention composed of hydroxyapatite which is non-resorbable and which will therefore retain its properties over time and remain in place while allowing = the osseointegration of a dental implant anchored later. In yet another embodiment, the device according to the invention composed of a mixture of tricalcium phosphate and hydroxyapatite makes it possible to provide a device according to the invention which is at least partially resorbable and which retains its properties over time.

It is understood that the present invention is in no way limited to the embodiments described above and that many modifications can be made thereto without departing from the scope of the appended claims.

Claims (19)

“CLAIMS” 1. Covering device arranged to promote bone regeneration of a bone defect site provided with a bone surface, said device being obtained by additive manufacturing and comprising at least one shell formed of a porous matrix which comprises a first inner face facing said bone defect site and a second outer face opposite said first face characterized in that the porous matrix extends at least partially between said first and second faces and has a series of pores of size IO between 50 and 1000 um and in that the device comprises at least one support pillar comprising a series of first end(s) connected to said first inner face of the shell and a series of second end(s) opposite to said bonded first end and arranged to rest on said bone surface of the bone defect site, said device being made of synthetic ceramic and arranged to delimit a cavity arranged designed to house a volume of bone to be regenerated and optionally to receive at least one bone regeneration material. 2. Covering device arranged to promote bone regeneration according to claim 1, wherein said shell has a U-shaped cross-section comprising a main wall from which two side walls extend in a substantially transverse direction, said main wall being provided with said first and second faces and formed from said porous matrix. 3. Covering device arranged to promote bone regeneration according to claim 1, wherein said shell has an L-shaped cross section comprising a main wall from which extends a side wall in a substantially transverse direction, said main wall being provided with said first and second faces and formed from said porous matrix. 4. Covering device arranged to promote bone regeneration according to claim 2 or claim 3, wherein said side walls each have an inner face and an outer face between which they extend and are formed of said porous matrix. 5. Covering device arranged to promote bone regeneration according to any one of claims 2 to 4, wherein said side walls each have an end connected to said main wall and a free end, arranged to be in contact with a bone material of said bone surface of the bone defect site or of a healthy area adjoining said bone defect. 6. Covering device arranged to promote bone regeneration according to one of claims 1 to 5, in which the pores of the said series of pores of the porous matrix have a size comprised between 100 and 900 μm, preferably between 150 and 850 μm, preferably between 200 and 800 μm, advantageously between 250 and 750 μm and in a particularly advantageous manner between 300 and 700 μm. 7. Covering device arranged to promote bone regeneration according to any one of the preceding claims, in which said at least one support pillar has an average diameter Dm of between 400 and 2000 μm. 8. Covering device arranged to promote bone regeneration according to any one of the preceding claims, wherein said at least one support pillar has a diameter D at all points equal to the average diameter Dm +/- 10%. 9. Covering device arranged to promote bone regeneration according to any one of the preceding claims, wherein said at least one support pillar is substantially cylindrical in shape. 10. A covering device arranged to promote bone regeneration according to any one of the preceding claims, in which the said at least one support pillar comprises a foot part, a body part and a head part, the foot part being the part arranged to rest on the bone surface of the bone defect site, the head part being the part linked to the first internal face of the shell, the body part being located between the said foot part and the said head part. 11. A covering device arranged to promote bone regeneration according to claim 10 wherein said at least one support pillar may comprise a series of ramifications which extend from the foot part and/or the body part and/or the or the head part of said at least one pillar. 12. Covering device arranged to promote bone regeneration according to any one of the preceding claims, in which the synthetic ceramic is composed of a material chosen from the group comprising hydroxyapatite, tricalcium phosphate, and their mixture. 13. Covering device arranged to promote bone regeneration according to any one of the preceding claims, wherein said porous matrix comprises a pore volume of between 1 and 50%. 14. Covering device arranged to promote bone regeneration according to any one of the preceding claims, in which the device occupies at most a volume of 30% relative to the volume of the bone defect to be regenerated, preferably at most a volume of 25 %, more preferably at most a volume of 20%, and possibly said bone regeneration material received in said cavity is crossed by said at least one support pillar. 15. Covering device arranged to promote bone regeneration according to any one of the preceding claims, in which said porous matrix comprises a thickness of between 500 and 10000 μm, preferably between 500 and 7500 μm, preferentially between 500 and 5000 μm, advantageously between 500 and 4000 μm. 16. Covering device arranged to promote bone regeneration according to any one of the preceding claims, in which said porous matrix and/or said at least one support pillar has a surface roughness of between 0.70 and 2.10 µm. , preferably between 0.80 and 2.00 μm, preferably between 0.90 and 1.90 μm, advantageously between 1.00 and 1.80 μm, particularly advantageously between 1.10 and 1.70 μm. 17. A method of manufacturing a covering device arranged to promote bone regeneration according to any one of claims 1 to 16, comprising the steps of a) parameterizing the bone defect to be filled, b) modeling said covering device arranged to promote bone regeneration, c) preparation of said device by additive manufacturing, d) collection of said covering device arranged to promote bone regeneration manufactured after elimination of residues accumulated in the porous matrix during additive manufacturing by blowing, immersion in a liquid. 18. A method of manufacturing a covering device arranged to promote bone regeneration according to claim 17, further comprising a step of sintering the device collected at a temperature between 1000°C and 1300°C, preferably between 1050°C and 1250°C, preferably between 1100°C and 1200°C. 19. A method of manufacturing a covering device arranged to promote bone regeneration according to claim 16 or claim 18, wherein said sintering takes place for a period of between 1 and 6 hours, preferably between 2 and 5 hours, preferably between 2 and 4 hours, preferably for a period of between 2.5 and 3.5 hours.