ITRM20110168A1 - SURGICAL DEVICE FOR THE RECONSTRUCTION OF BONE STRUCTURES. - Google Patents

Description

SURGICAL DEVICE FOR THE RECONSTRUCTION OF BONE STRUCTURES

DESCRIPTION

Field of invention

The present invention refers to a surgical device suitable for use in the reconstruction of bone structures, particularly suitable for use after a partial or total resection, following traumatic events and in general in any case in which a bone portion is absent and there is a need for a reconstruction and, typically, also for a stabilization of the residual bone segments.

The device is particularly suitable for use in maxillofacial surgery, and especially mandibular and maxillary.

Background of the invention

Bone reconstruction operations are practiced today in many areas of the body and are often preceded by the removal of damaged or diseased segments that are the subject of subsequent reconstruction.

In the specific field of maxillofacial surgery, mandibular reconstruction is generally preceded by a pre-prosthetic surgery following traumatic events, by a reduced bone resection required by benign neoplasms or by demolition operations that remove oncological processes on bone portions also very large. In these cases, the reconstruction operation can take place in a single session at the same time as the resection / demolition or be postponed to a second operation.

In the aforementioned possible resection / demolition phase preliminary to the mandibular reconstruction, surgical cutting guides are used. The known cutting guides consist of a resting surface on the bone to be cut, which surface has a thin slot for the insertion of a resection blade.

In order to ensure the accuracy of the final result, it is essential an ad hoc planning of each intervention based on the local anatomy of the specific patient and an optimal coordination between any resection surgery and the subsequent reconstructive surgery. To this end, it is necessary to ensure the correct transfer of what was planned in the pre-operative phase into the real surgical application, in particular by guiding the surgeon during the resection phase according to planned cuts and ensuring that the bone segment is absent or removed. is perfectly congruent with the portion of graft material used in the reconstruction. In this regard, it should be borne in mind that when a bone portion is removed, the residual bone ends can undergo important dislocations, mainly due to muscle tension. In the specific case of oncological surgery of the mandible, when the bone continuity is dissected, the two residual stumps undergo a violent contracture and dislocation that can make it impossible to restore the quo ante situation to start the reconstructive phase, with a consequent inadequate final condylar disposition. and problems of malocclusion.

To try to overcome this drawback, the residual bone abutments are nowadays stabilized through the so-called â € œpre-platingâ € technique, that is through the use of standard rigid fixation plates available on the market, which the surgeon must bend manually to hoc for each patient during surgery and / or in a pre-operative phase and whose ends are precisely fixed on the respective forming bone stumps before resection.

In the traditional pre-plating technique, the same manually bent plate is used both for the resection phase and for the subsequent reconstruction phase. In the so-called â € œdouble pre-platingâ € technique, two distinct plates are used, one for the resection phase and one for the reconstruction phase.

The manual bending of the plates can be facilitated by the use of three-dimensional models of the bone portions of interest, obtained through rapid prototyping techniques starting from virtual bone reconstructions based on computed tomography data or equivalent data .

The reconstructive graft material, suitably modeled, is then connected, typically by means of titanium screws, to a fixation plate. This graft material can be autologous tissue - for example, in the mandibular area, a free re-vascularized flap of fibula, iliac crest, scapula or other - or heterologous or artificial tissue.

Main disadvantages of the known art

The surgical techniques of resection and subsequent bone reconstruction introduced above and the associated surgical devices of the known technique that implement them have some significant drawbacks, which are illustrated below.

First of all, the need to jointly use two or three distinct devices in the resection phase - generally two cutting guides and at least one stabilization plate of the forming bone stumps - makes the operation rather long and complex, requiring numerous locking operations. of the same devices on the bone portions and therefore the application of a large number of screws.

Furthermore, the absolute and relative positioning of the stabilization plate and the guides is entrusted to the expertise of the surgeon, evidently at the expense of the accuracy of the cut and the final congruence between the removed portion and the reconstructed segment.

Furthermore, the surgical guides of the known technique described in the previous section do not allow a complete and correct view of the bone during the cutting operation, with the risk of injury to anatomical structures to be preserved placed behind the bone to be dissected.

The slot-like structure of the known guides does not allow to check, during the cut, neither the exact position nor above all the orientation of the blade.

As regards the stabilization of the residual bone portions for the purposes of the reconstruction phase, the aforementioned pre-plating technique is also in this case rather complex to apply.

Furthermore, it does not however allow to maintain a fully satisfactory positioning of the bone abutment (s) and consequently a suitable congruity between the removed segment and the reconstructed one. As mentioned above in relation to the resection phase, this is due to the reduced accuracy of positioning, both in an absolute sense of the plates with respect to the body district of interest and in a relative sense of the stabilization plates applied in the reconstructive phase compared to the devices used in the previous one. resection phase.

Furthermore, as regards the post-operative phase following the reconstruction intervention, the known devices do not allow a stable, reliable and repeatable maintenance in situ of the graft material, with the risk of even significant dislocations of this material. Such displacements can result in a failure of the tissue to fuse with the residual structures, a morphologically incorrect formation of the reconstructed structure, even major infections and in general a non-optimal orthognathic reconstruction.

It will be understood that even if the drawbacks described up to now are particularly felt in the specific case of mandible and maxilla reconstruction surgery, they are also found in other interventions having as their object the resection and / or reconstruction in different body districts.

Furthermore, said drawbacks are also encountered in the case of partial resections which do not necessarily involve the removal of an entire bone segment which leaves two distinct residual stumps free.

Summary of the invention

On the basis of what has been described in the previous sections, the technical problem posed and solved by the present invention is that of providing a surgical device for the reconstruction of bone structures which allows to overcome the drawbacks mentioned above with reference to the known art.

This problem is solved by a device according to claim 1.

Preferred features of the present invention are present in the dependent claims thereof.

The present invention provides some relevant advantages. The main advantage consists in the fact that the surgical reconstruction device of the invention ensures a stable, reliable and repeatable maintenance in situ of the graft tissue and therefore an optimal orthognathic reconstruction. Furthermore, the reconstructive surgery is simplified.

To obtain these advantages, the device has a main retention body, preferably in the form of a bar, to keep in connection - and therefore stabilize - the residual bone portions and prevent them from undergoing dislocations due for example to muscle tension. Associated with this main retention body are means for supporting the reconstructive graft material and fixing means, in particular perforated plates suitable for locking by means of screws. The device also comprises specific recording means for the planned and univocal positioning of the device with respect to the patient's body district.

The presence of the recording means allows great accuracy both in the absolute positioning of the device itself on the patient's body structure and in the relative positioning with respect to a guide device possibly used in the pre-reconstructive resection phase. On the contrary, the manually adapted plates of the known art do not contain any reference for positioning on the patient's bone structure.

In particular, the registration means of the device of the invention can incorporate a surface or other means specifically dedicated to relative positioning with respect to the aforementioned resection guide device.

As said, all the aforesaid components are integrated in the same device and preferably rigidly connected, in particular made integral, with each other.

According to a preferred embodiment, the fastening and / or adjusting means are double and placed at respective opposite ends of the main retention body with respect to the part to be removed.

The main retention body and the associated fixing and registration means can be designed in the pre-operative phase on the basis of the specific anatomy of the patient on which they are to be applied, so as to be immediately associated with the body structure to be resected - where required, matching perfectly with the latter - without any need for manual modeling by the surgeon.

The reconstruction device of the invention can therefore be custom designed on the specific anatomy of the patient as part of an integrated system designed precisely for resection and subsequent bone reconstruction. This integrated system preferably also comprises the aforementioned resection guide device.

This guiding device includes, in its most general definition, one or more guiding elements for the resection of a bone portion, in particular of the mandible, according to cutting surfaces identified in the planning phase of the intervention. Furthermore, the guiding device also has a main retention body, preferably in the form of a bar, to keep the parts involved in the resection connected and prevent them from being dislocated after removal. The device then comprises fixing means, in particular perforated plates suitable for locking by means of screws, and registration means for its univocal positioning with respect to the patient's body district.

In this case too, the device is unitary, since all the aforementioned components are integrated in the same structure and preferably rigidly connected, and in particular made integral, with each other.

Also in the case of the guiding device, the main retention body and the associated fixing and recording means can be designed in the preoperative phase on the basis of the specific anatomy of the patient on which they are to be applied, so as to be immediately associable with the body structure to be resect - where required, matching perfectly with the latter - without any need for manual shaping by the surgeon.

Preferably, the overall configuration of the guiding device provides that the main retention body or a part of it is placed at a distance from the bone segment to be resected, so as to allow the surgeon to operate without visual obstacles, with obvious advantages for accuracy. intervention and limiting the risk of injury to anatomical structures to be preserved.

Again according to a preferred embodiment, also in this case the fastening and / or recording means are double and placed at respective opposite ends of the main retention body with respect to the part to be removed, further favoring the surgeon's vision.

Still according to a preferred embodiment, the guiding elements comprise guiding surfaces, for example flat, which allow to univocally guide both position and orientation of the cutting instrument during the resection, allowing the accurate execution of planned cuts.

The provision of corresponding recording means in this guiding device for use integrated with the reconstruction device allows to emphasize the attainment of the aforesaid advantages. In fact, the sequential use of the guide and reconstruction devices on the patient's bone structure is therefore constrained and unambiguous, guaranteeing suitable congruity between the removed segment and the reconstructed one.

Other advantages, characteristics and methods of use of the present invention will become evident from the following detailed description of some embodiments, presented by way of non-limiting example.

Brief description of the figures

Reference will be made to the figures of the attached drawings, in which:

Figures 1A and 1B each show a perspective view of a surgical guide device according to a first preferred embodiment, when applied to a mandible before and after cutting respectively;

Figures 2A and 2B each show a perspective view of a surgical guide device according to a second preferred embodiment, when applied to a mandible before and after cutting respectively;

Figures 3A and 3B each show a perspective view of a surgical guide device according to a third preferred embodiment in the application on a mandible before and after cutting respectively;

Figure 4 shows a perspective view, in the application on a mandible, of a first preferred embodiment of a surgical reconstruction device according to the invention which is suitable for use, in its general meaning, in association with any of the guiding devices of the previous figures, and which is shown in particular as suitable for coupling in support of the device of Figure 1A;

Figure 4A shows an enlarged detail of the reconstruction device of Figure 4;

Figure 5 shows a perspective view, when applied to a mandible, of a second preferred embodiment of a surgical reconstruction device according to the invention, which is suitable for use, in its general meaning, in association with any one of the guiding devices of Figures 1A to 3B, and which is shown in particular as suitable for sequential coupling with the device of Figure 2A;

Figure 5A shows an enlarged detail of the reconstruction device of Figure 5;

Figure 6 shows a perspective view, in the application on a mandible, of a third preferred embodiment of a surgical reconstruction device according to the invention which is suitable for use, in its general meaning, in association with any of the guiding devices of Figures 1A to 3B, and which is shown in particular as suitable for coupling in support of a device similar to that of Figure 1A;

Figures 7A to 7C refer to the guiding devices of Figure 1A and the reconstruction of Figure 4 respectively applied jointly on a mandible, in a respective phase of mutual positioning and showing perspective views thereof;

Figures 8A to 8C refer to the guiding device of Figure 2A and to a reconstruction device similar to that of Figure 4 applied jointly on a mandible, in a respective phase of an alternative mode of reciprocal positioning and showing perspective views thereof;

Figures 9A to 9C refer to the guiding devices of Figure 2A and reconstruction of Figure 5 respectively applied in sequence on a mandible, in a respective phase of an alternative mode of reciprocal positioning and showing perspective views thereof;

Figure 10 shows a perspective view, in the application on a mandible, of a fourth preferred embodiment of a surgical reconstruction device according to the invention which is suitable for use, in its general meaning, in association with any of the guiding devices of Figures 1A to 3B, and which is shown in particular as suitable for coupling in support of the device of Figure 1A;

Figure 11 shows a perspective view, in the application on a mandible, of a fifth preferred embodiment of a surgical reconstruction device according to the invention, which is suitable for use, in its general meaning, in association with any one of the guiding devices of Figures 1A to 3B, and which is shown in particular as suitable for sequential coupling with the device of Figure 2A;

Figure 12 shows a perspective view, in the application on a mandible, of a sixth preferred embodiment of a surgical reconstruction device according to the invention which is suitable for use, in its general meaning, in association with any of the guiding devices of Figures 1A to 3B, and which is shown in particular as suitable for coupling in support of the device of Figure 1A;

Figure 13 shows a perspective view, in the application on a mandible, of a seventh preferred embodiment of a surgical reconstruction device according to the invention, which is suitable for use, in its general meaning, in association with any one of the guiding devices of Figures 1A to 3B, and which is shown in particular as suitable for sequential coupling with the device of Figure 2A;

Figure 14 shows a perspective view, in the application on a mandible, of an eighth preferred embodiment of a surgical reconstruction device according to the invention, which is suitable for use, in its general meaning, in association with any one of the guiding devices of Figures 1A to 3B, and which is shown in particular as suitable for sequential coupling with the device of Figure 2A;

Figure 15 refers to a ninth preferred embodiment of a surgical reconstruction device, showing a perspective view of it when applied to a mandible; And

Figure 16 shows a schematic flow diagram relating to a preferred embodiment of a method of manufacturing one or more of the devices of the preceding figures.

Detailed description of preferred embodiments

With initial reference to Figures 1A and 1B, a unitary surgical guide device according to a first preferred embodiment is generally denoted by 1. The guide device 1 is suitable for use for bone resection, in particular mandibular.

The guiding device 1 first of all comprises a pair of substantially flat guiding surfaces, denoted respectively by 21 and 22, each suitable for defining a unilateral guide for a blade or other cutting tool and in particular for receiving the latter in attestation on of it.

The two guiding surfaces 21 and 22 are rigidly connected or integral with a main retention body 3, which in this example has an oblong development and is substantially in the form of a bar. In particular, the two guiding surfaces 21 and 22 are arranged spaced apart from each other along the retention bar 3, substantially at or near respective longitudinal ends of a central section of the latter. The two guide surfaces 21 and 22 also have, again in the present example, a substantially orthogonal development to that of the bar 3.

Variants of embodiment may provide for guiding means other than surfaces 21 and 22 or a different number of guiding surfaces. In particular, inclined surfaces with respect to the aforementioned direction orthogonal to the bar 3 can be provided. Furthermore, the guiding surfaces can have a configuration designed for particular cutting profiles, for example stepped. Furthermore, the guiding surfaces or equivalent means to them can be rigidly connectable to the main retention body in a pre-operative phase or after the in situ application of the device. The guide means could also be disassembled during the operation, to simplify the phases following the actual cut.

The retention bar 3 is designed to be interposed as a bridge between the residual ends of a body structure affected by the resection. In the present example, the bar 3 has a substantially "U" or bracket conformation, providing the aforementioned central longitudinal section, denoted by 30, which develops substantially parallel to the bone segment to be removed and opposite lateral sections, respectively 31 and 32, folded in a substantially orthogonal direction to the central portion 30 to allow connection with the bone structure involved in the resection. As mentioned above, the two guiding surfaces 21 and 22 are arranged at or near the ends of the central longitudinal section 30.

Said â € œUâ € or bracket conformation allows the retention bar 3 to be arranged, in use, in a position at a distance from the bone portion to be resected, to the advantage of the surgeon's clarity of vision.

The aforementioned connection between the device 1 and the body structure is obtained by means of bilateral fixing means, which are also rigidly integral with or integral with the retention bar 3 at the ends of the lateral portions 31 and 32 of the latter. In the present example, the fastening means are formed by two side plates, respectively 41 and 42, as mentioned, each integral with a respective lateral portion 31 or 32 of the bar 3 and each provided with fastening holes 40.

The device 1 then comprises adjustment means, also bilateral and arranged at the ends of the lateral portions 31 and 32 of the retention bar 3. These means are also integral or integral with the fastening means. In particular, the recording means comprise a pair of shaped portions, 51 and 52 respectively, each immediately contiguous and integral with a respective fixing plate 41 or 42 and each reproducing the local morphology of the body structure on which it is applied.

This customized shaping can be obtained in a pre-operative phase of planning the intervention and designing the devices used therein, as will be clarified later on.

In the present example, the shaped recording portions 51 and 52 each have a substantially hook-like conformation.

The shaped recording portions 51, 52 are therefore suitable for allowing a predetermined positioning of the device 1 on the bone structure.

In the present preferred example, the guiding device 1 - and specifically the recording means thereof - also has, in correspondence with or proximity to at least one of the shaped portions 51 and 52 and / or of the fixing plates 41 and 42, at least one surface coupling device specifically dedicated to the relative positioning of a reconstruction device to be used in a subsequent intervention phase and which is described below. In the present example, this coupling surface is provided in correspondence with a lower portion of the fixing plate 41 and a lateral portion of the shaped portion 51 and denoted by 53.

Figures 2A and 2B refer to a second embodiment of the guiding device, which is described below only with reference to the aspects which differentiate it from the first embodiment illustrated above.

In this device, denoted as a whole with 101, the main retention body, here denoted with 300, is always oblong in shape and in particular of a bar, but has a substantially arcuate development. Furthermore, two guiding surfaces are directly provided at its longitudinal ends, 210 and 220 respectively, which extend in a substantially orthogonal direction to the bar 300 itself and allow it to remain spaced from the portion to be resected.

The guide surfaces 210 and 220 are then associated with fixing means 41 and 42 and recording means 51 and 52 similar to those already described above in relation to the first embodiment.

Figures 3A and 3B then refer to a third embodiment of the guiding device, which also in this case is described below only with reference to the aspects that differentiate it from the first embodiment illustrated above.

The representation of these figures is purely schematic. In particular, the size and profile of the surgical cuts shown and of the corresponding surfaces of the device are to be understood as purely illustrative.

The aforementioned device, denoted as a whole with 102, is intended in particular for so-called `` three-wall '' resections, i.e. in which the complete removal of a bone segment that leaves two free stumps is not foreseen, but the ™ removal of a bone portion that does not affect the continuity of the segment as a whole. In this case, as visible in the sequence of Figures 3A and 3B, also the main retention body, denoted here with 301, could have a guiding function of the cutting instrument in the intermediate part of the resection, thus assisting the function of the two guiding surfaces 21 and 22. For this purpose, the main retention body 301 is in the form of a bar and has an upper guiding surface 302 which in the present example is substantially square-shaped.

It will be understood that each of the embodiments of the guiding device described here may in turn also have in combination one or more of the variants illustrated with reference to one of the other embodiments.

With reference now to Figures 4 and 4A, a unitary surgical device for the reconstruction of bone segments according to a first preferred embodiment of the invention is generally denoted with 100. The reconstruction device 100 is suitable for use for the stabilization of residual bone segments following, for example, a resection, and is suitable for supporting a reconstruction material, particularly in the mandibular area.

The reconstruction device 100 comprises a main retention body 103, which also in this example has an oblong development and is substantially in the form of a bar. The retention bar 103 is designed to be interposed as a bridge between the residual ends of a bone structure involved in the reconstruction.

Furthermore, this reconstruction device 100, and in particular its main retention body 103, has a development such as to represent the ideal profile of the bone portion before resection (in the present example a portion of the mandibular branch).

The connection between the device 100 and the bone structure is obtained by means of bilateral fixing means, rigidly integral with or integral with the retention bar 103 at its longitudinal ends. Also in the present example, the fixing means are formed by two side plates, 141 and 142 respectively, each provided with fixing holes 140.

The reconstruction device 100 also comprises recording means suitable for allowing a predetermined positioning of the device itself on the body structure. In the present example, these registration means comprise a pair of marking elements in the form of projections, 155 and 156 respectively, each rigidly integral or integral with the retention bar 103 at a respective longitudinal end thereof. In the present example, each projection 155, 156 is interposed between the respective end of the bar 103 and a respective fixing plate 141, 142. Preferably, these projections are present both on the external surface and on the internal surface of the reconstruction device 100.

A variant embodiment may provide that the marking elements are in the form of recesses or other.

As can be appreciated from Figure 4, the aforementioned marking elements 155, 156 or the equivalent means - allow to position the reconstruction device 100, and in particular the main retention body 103 of this, â € œ flushâ € with the residual surfaces resulting from a previous resection or a previous traumatic or other event.

Furthermore, in the present example the registration means also comprise, in correspondence with or proximity to the fixing plates 141 and 142, at least one coupling surface specifically dedicated to the relative positioning of the guide device 1 described above. In the present example, this surface is provided in correspondence with an upper / lateral portion of the fixing plate 141 and denoted by 153 as indicated in Figure 4A.

The specific mutual positioning modes of the guiding device 1 and of the reconstructing device 100 as allowed by the respective coupling surfaces 53 and 153 of the respective recording means are illustrated in the sequence of Figures 7A-7C. In particular, once the resection phase is finished and with the guiding device still in position (Figure 7A), the reconstruction device 100 is positioned in the region of interest in such a way that its coupling surface 153 is brought to mate with the complementary surface 53 of the guiding device (Figure 7B), also making use of the reference provided by the projections 155 and 156 for positioning on the bone. The reconstruction device 100 can now be locked to the bone at the fixation means 141 and 142 and the guiding device can be removed.

It will be appreciated that the guiding device as described above and the reconstruction device can however also be used independently of each other and not necessarily in interventions performed at the same time.

An alternative mode of reciprocal positioning between a guiding device and a reconstruction device, and in particular in this case between the reconstruction device 100 and the guiding device 101, is illustrated in the sequence of Figures 8A-8C. In this case, the two devices are referred to each other using the same locking holes. In other words, the guiding device 101 is locked on the bone in correspondence with the holes 40 of the relative fixing plates 41 and 42 (Figure 8A). After the removal of the guiding device (Figure 8B), the reconstruction device 100 is locked on the bone using the same holes already drilled on the latter (Figure 8C), making these holes on the bone match up with the holes 140 of plates 141 and 142.

This blocking methodology could in itself be subject to separate protection.

A further alternative mode of reciprocal positioning between a guiding device and a reconstruction device, and in particular in this case between the reconstruction device 203 and the guiding device 101, is illustrated in the sequence of Figures 9A-9C.

In this case, the guiding device 101 is first applied and the bone cut is performed (Figure 9A). At this point the guiding device 101 is removed (Figure 9B) and the reconstruction device 203 is applied (Figure 9C). In the illustrated sequence, the two devices 101 and 203 share the same locking holes on the bone, but are not simultaneously fixed or present on it, each being positioned uniquely with respect to the bone itself by means of its own recording means respectively 51 and 251.

Returning now to Figures 4 and 4A, the reconstruction device 100 also comprises support means of graft reconstructive material. In the present example, these means consist of a plurality of holes 150 arranged along the main retention body 103 and adapted to receive suitable connecting elements to said graft material or to a further support structure thereof. Preferably, the holes 150 are arranged according to a predetermined configuration corresponding to the planning of the intervention based on the specific anatomy of the patient and / or on the specific needs and construction methods. Alternatively, they can be arranged according to a standard configuration, for example equally spaced along the main retention body 103.

The aforesaid projections 155, 156 or equivalent means make it possible to identify the suitable area for mounting and fixing the reconstructive grafting material â € œbenchâ € before fixing the device with the reconstructive grafting material on the body structure.

Figures 5 and 6 and 10 to 15 each show a respective further preferred embodiment of the reconstruction device of the invention. Each of these embodiments is described below only with reference to the aspects that differentiate it from the first embodiment illustrated above or from the previously described embodiments. Also in this case, each of the embodiments of the reconstruction device can in turn have in combination one or more of the variants illustrated also with reference to one of the other embodiments.

Furthermore, the same reciprocal positioning modes can be applied to each of the embodiments of Figures 5, 6 and 10 to 14 with a guide device 1, 101 or 102 already described above, in particular in relation to Figures 7A-7C , 8A-8C and 9A-9C.

Figures 5 and 5A show a second embodiment of the reconstruction device, denoted here as a whole with 200. In this embodiment, the device comprises a main retention body 203 of oblong shape, and in particular substantially in the form of a bar.

Furthermore, this reconstruction device 200 and in particular the main retention body 203 has a development such as to represent the ideal profile of the bone portion before resection (in the present example a portion of the mandibular branch).

At the longitudinal ends of the bar 203 there are means for fixing to residual body portions, which, similarly to the first embodiment, are in the form of plates or plates 241 and 242 carrying holes 240.

Associated with each plate 241, 242, registration means are provided, integral or integral with the plate 241, 242 itself. Said recording means comprise a pair of shaped portions 251 and 252, each immediately contiguous and integral with a respective fixing plate 241 or 242 and each reproducing the local morphology of the body structure on which it is applied. These portions 251, 252 are substantially similar to the shaped portions 51 and 52 described above in relation to the guiding device.

This customized shaping can be obtained in a pre-operative phase of planning the intervention and designing the devices used therein, as will be clarified later on.

Also in the reconstruction device 200 the shaped recording portions 251 and 252 each have a substantially hook-like conformation.

The shaped recording portions 251 and 252 are therefore suitable for allowing a predetermined positioning of the device 200 on the bone structure.

In the present example, the recording means also comprise a pair of projections 255, 256 similar in function and location to those of the first embodiment and denoted therein with 155 and 156. Also in the present example, these projections are preferably present both on the surface external and internal surface of the reconstruction device 200.

In a variant embodiment, in association with the recording portions 251 and 252 and the projections 255 and 256, a coupling surface with the guide device 1, 101 or 102 illustrated above can also be provided, similarly to what is described in relation to the first embodiment.

Figure 6 shows a third embodiment of the reconstruction device, denoted as a whole with 110.

The device 110 differs from the first embodiment in that it provides, at one end of the retention body 103, a portion which forms a prosthetic element 111, preferably an articular element. The prosthetic element 111 is fixed to, and preferably integral with, the retention body 103. At the other end, the retention bar 103 provides a fixing plate 141 and an associated marking element 155 similar to that of the first embodiment.

Figure 10 shows a fourth embodiment of the reconstruction device, here denoted by 400.

The device 400 comprises a main retention body 403, which also in this example has an oblong development and is substantially in the form of a bar. The retention bar 403 is designed to be interposed as a bridge between the residual ends of a bone structure involved in the reconstruction.

The connection between the device 400 and the bone structure is also obtained in this case, similarly to the first embodiment, by means of bilateral fixing means, rigidly integral or integral with the retention bar 403 at its longitudinal ends. Also in the present example, the fixing means are formed by two lateral plates, respectively 441 and 442, each provided with fixing holes 440.

Support means of a reconstructive graft material are then permanently bound to the retention element 403. In the present example, these support means comprise a shaped structure 450, preferably of the reticular type, suitable for receiving and containing such material inside.

This shaped structure 450 has a development such as to represent the ideal volume of the bone portion before resection (in this case a portion of the mandibular branch).

The support structure 450 considered here is of the â € œclosedâ € type, in the sense of having a cylindrical configuration that requires the insertion of the material before fixing it in situ in the patient's body through the openings at the ends of the support structure. This support structure 450 is particularly suitable for receiving particulate autologous and heterologous material implants. The reticular configuration ensures proper blood supply to the graft material.

In a variant embodiment, the containment structure 450 and / or the main retention body 403 can be provided with means of reciprocal removable connection, to fix the first on the second after the latter has been locked to the bone structure of the subject.

Furthermore, in a further variant of embodiment, the containment structure can be made in two parts that are removably connected and therefore can be dismantled. This can be helpful when removing the reconstruction device which leaves only the reconstructive material in place.

The containment structure 450 can reproduce the local morphology of the bone segment to be reconstructed and in this sense, by means of its overall dimensions and the correspondence of its peripheral surfaces with the residual anatomical structures, create a recording means for the correct positioning of the reconstruction device. same.

In the present example, however, dedicated registration means are provided comprising a pair of marking elements in the form of projections 455, 456 similar to those already described.

Preferably, as mentioned above, the recording means also provide a specific conformation of the ends of the containment structure 450 and of the fixing plates 441 and 442, suitable for reproducing the local morphology of the body portion to which they are associated.

Also this structure can be positioned relative to a surgical guide device according to the methods already described above.

In general terms, the reconstruction material contained in the support structure 450 can be autoplastic, homoplastic, heteroplastic, alloplastic or obtained by combination of the aforesaid modalities. For example, bone reconstruction / regeneration can take place through the grafting of a free revascularized fibula flap, hydroxyapatite scaffold / ceramic material / ceramic composite or bone particulate, in accordance with the clinical and surgical needs of the specific clinical case.

Correspondingly, the support means of the reconstruction device can only have a supporting function (for example in the case of grafting of a free revascularized fibula flap or of hydroxyapatite / ceramic material / ceramic composite scaffold), as in the first three embodiments presented. above, or also perform a containment function (for example in the case of grafting of bone particulate or hydroxyapatite elements / ceramic material / ceramic composite), as in the embodiment considered here and in those of Figures 11 to 14 which will be described below.

Figure 11 shows a fifth embodiment of the reconstruction device, denoted by 401. This embodiment differs from the fourth embodiment first of all in that it provides a containment structure 451 having a lateral longitudinal opening that allows insertion of the reconstruction material even after the implantation of the reconstruction device 401 in situ.

Furthermore, the device 401 provides, similarly to the second embodiment, recording means which comprise a pair of shaped portions 251 and 252 associated with respective lateral fixing plates 241 and 242 and each having a substantially hook-like shape.

Figure 12 shows a sixth embodiment of the reconstruction device, denoted here by 600. This embodiment differs from the fourth embodiment in that it provides a containment structure 650 in the form of a perforated casing.

Figure 13 shows a seventh embodiment of the reconstruction device, denoted here by 700. This embodiment differs from the fifth embodiment in that it provides a containment structure 751 with a broad-meshed and substantially shaped lattice configuration. cradle, that is equipped with a wide upper longitudinal opening, to be used preferably in the case of joint use with castomized ceramic scaffolds.

Figure 14 shows an eighth embodiment of the reconstruction device, denoted here by 800. This embodiment differs from the second embodiment in that the support means comprise, in addition to the holes 150, also three of support arms 850 integral with a main retention body 803 and spaced apart along the development of the latter. Means for connection to the reconstruction material and / or to a further support structure thereof, in the form of connection holes, are provided on each arm.

Variants of embodiment can provide a different number of support arms and a different location thereof, to be used preferably in the case of joint use with castomized ceramic scaffolds.

Figure 15 shows a ninth embodiment of the reconstruction device, denoted here by 900.

In this embodiment, the reconstruction device provides support means which comprise a shaped structure 950 able to establish a shape coupling with the reconstructive material, denoted here with 500. Preferably, and as shown in said figure, the structure 950 has an enveloping conformation for the reconstructive material 500.

In particular, the support structure 950 has a reticular configuration which integrates a plurality of holes 904 each suitable for receiving a locking means, typically a screw 901, of the reconstruction material. The presence of the holes 904 will also favor the blood supply to the reconstructive material. It will be appreciated that, by virtue of the enveloping conformation of the structure 950, the locking means serves only to support the reconstruction material 500, the stability of which is fully guaranteed by the aforementioned enveloping configuration.

In this embodiment, a main retention body 903 is provided which connects a residual bone end with the reconstruction material 500 and which is obtained as a single body with the support structure 950, the latter representing the End of the retention body 903. Furthermore, also in this case bilateral fastening means are provided, made here as a fastening plate 941 protruding from the retention element 903 and as the aforementioned plurality of holes 904 obtained on the structure 950.

The fixing plate 941, the main body 903 and the support structure 950 are each shaped according to the local anatomy of the residual bone and of the reconstruction material, this shaping realizing registration means in the sense already illustrated.

It will also be understood that it is possible to provide an assembly comprising the reconstruction device as described up to now and the associated reconstructive material fixed or fixable to the support means of the device itself.

In a preferred embodiment variant, the reconstructive material integrates stem cells.

Furthermore, in a further variant, elements specifically dedicated to the subsequent application of dental implants can be applied on the reconstructive material of the assembly or on the support means of the assembly or its reconstruction device.

As shown in Figure 15 and as stated above in relation to the corresponding embodiment, the graft material 500 is locked onto the structure 950 by a single connecting means 901, typically a screw.

Obtaining a suitable hole in the grafting material presents unresolved problems in the known art, due to the risk of generating fractures or cracks in the latter. According to an innovative methodology that could be subject to separate protection with respect to the devices described up to now, this hole can be obtained by using in sequence a plurality of diamond cutters, or equivalent tools, of increasing diameter to progressively drill and enlarge the hole itself. Preferably, the final hole is undersized in diameter by approximately 0.2-0.3 mm with respect to the screw or other connecting means to be applied.

A specific preferred implementation of this method for connecting a surgical screw or equivalent locking device to the graft material involves the sequential use of:

∠’a diamond drill with a diameter of 1.2 mm, without irrigation;

∠’a diamond cutter with a diameter of 1.4 mm; And

∠’a 1.6 mm diamond bur.

At this point a 1.9 mm diameter titanium screw can be supplied and this can be inserted with a manual screwdriver.

With reference now to Figure 16, as already mentioned, each of the guiding and reconstruction devices described so far as well as the grafting material, if artificial, can be designed and implemented through a pre-operative planning of the intervention based on the use of images computed tomography (CT), or equivalent data, of the body area of interest of the specific patient and on rapid prototyping techniques that allow to reproduce, in these devices and / or in one or more parts of them, a morphology matching that of the body area, and in particular bone structure, residual or to be reconstructed.

Figure 16 shows a possible methodology for this planned realization of the devices and grafts, referring to the specific example of the mandible and to the coordinated realization of a resection guide device (â € œsurgical guideâ € in Figure 16) and of a reconstruction device (â € œstabilization structureâ € in Figure 16).

The starting point is the execution of the CT (or magnetic resonance), which provides images in DICOM format that can be loaded into software dedicated to the visualization and reconstruction of the 3D model of the bone structure of interest. The pre-operative CT scan (or magnetic resonance imaging) also serves the surgeon to plan his surgery and identify the bone portion of the mandible to be removed / reconstructed.

The customized device is then designed in the CAD environment, after importing the 3D model of the mandible, through the combined design of the two components (surgical guide and stabilization structure).

In the CAD design environment, the cuts set by the surgeon are reproduced to make it possible to virtually dissect the mandible and remove the bone portion identified by the surgeon. So that these cuts can then be reproduced exactly in the real intraoperative environment, the guiding device is designed in an individualized way, through the functional characteristic elements described above. The resulting guiding device therefore allows the surgeon to make the most precise cut possible in a clinical environment compared to what was designed in a virtual environment.

Subsequently, again in the CAD design environment, the relative reconstruction device is designed, with the function of supporting or even containing the graft material chosen by the surgeon according to the clinical needs of bone reconstruction / regeneration. This device is designed in an individualized way through the functional characteristic elements described above, in order to have the degree of rigidity necessary to support the functional loads and guide the correct mandibular reconstruction according to the original and optimal shape of the bone structure.

The stabilization device is made in such a way as to be perfectly congruent with the bone removed with the indication of the guiding device and to have a constrained and unambiguous positioning on the mandible with respect to this. Finally, the realization of the devices takes place through direct production through the use of additive techniques of rapid prototyping that use, for example, metal powders.

As already mentioned above, even if the invention and the devices associated with it have been described with reference to the specific application for surgery of the mandibular arch, it is suitable for use in other areas of the body, and particularly the ™ maxillary arch.

It will also be understood that even if the invention and the devices associated with it have been described with reference to a support and fixing on residual bone stumps of the mandible, they also find application in relation to different anatomical situations, in which a support and / or at least partial fixation on one or more residual dental elements.

The guiding, stabilizing and reconstructing devices described above can be made of metal.

The present invention has been described heretofore with reference to preferred embodiments. It is to be understood that other embodiments may exist which refer to the same inventive nucleus, as defined by the protection scope of the claims reported below.

Claims (25)

CLAIMS 1. Unitary surgical device for reconstruction (100; 200; 400) of bone structures, for use in particular in the mandibular and maxillary areas, comprising: ∠’a main retention body (103; 203; 403), capable of being associated with one or more residual parts of a body structure to be reconstructed; ∠’fastening means (141, 142; 241, 242; 441, 442), designed to lock said main retention body (103; 203; 403) on one or more residual parts of the structure to be resected; â ’support means (150; 450) of the reconstruction material; And ∠’recording means (153; 251, 252; 455, 456), designed to allow a predetermined positioning of the device (100; 200; 400) on the body structure. Device (100) according to claim 1, wherein said main retention body (103) has an oblong development and is preferably in the form of a bar. Device (400) according to claim 1 or 2, wherein said support means (450) are adapted to contain the reconstruction material. Device (400) according to any one of the preceding claims, wherein said support means comprise a shaped structure (450) adapted to receive the reconstruction material. Device (400) according to the preceding claim, in which said shaped structure (450) has a reticular configuration. Device (401; 700) according to claim 4 or 5, wherein said shaped structure (451; 751) has an opening suitable for allowing the introduction of the reconstruction material even after the implantation of the device in situ. Device (800) according to any one of the preceding claims, wherein said support means comprise at least one support arm (850) fixed or adapted to be fixed on the reconstruction material or on a further support structure thereof. Device (900) according to any one of the preceding claims, wherein said support means comprise a shaped structure (950) able to establish a shape coupling with the reconstruction material (500). Device (900) according to the preceding claim, wherein said shaped structure (950) has an enveloping conformation for the reconstruction material (500). Device (100) according to any one of the preceding claims, wherein said support means comprise one or more holes (150) for connection to the reconstruction material. Device (100) according to any one of the preceding claims, in which said support means (150) are arranged at least partially in correspondence with said main retention body (103). Device (100) according to any one of the preceding claims, wherein said fastening means (141, 142) are directly connected to, and preferably integral with, said main retention body (103). Device (100) according to any one of the preceding claims, wherein said fastening means comprise a plurality of fastening holes (140) to the body structure. Device (100) according to any one of the preceding claims, wherein said registration means comprise at least one marking element (155, 156), preferably in the form of a ridge or recess, preferably obtained on said main retention body (103) and preferably present both on an external surface and on an internal surface of said main retention body (103). Device (100) according to any one of the preceding claims, wherein said recording means comprise a shaped portion which reproduces the local morphology of the body structure (251, 252). Device (100) according to any one of the preceding claims, wherein said recording means comprise a shaped portion (153) which reproduces the local morphology of an associated resection guide device (1). Device (100) according to any one of the preceding claims, wherein said recording means comprise a substantially hook-shaped portion (251, 252). Device (100) according to any one of the preceding claims, wherein said recording means (155, 156) are immediately contiguous and preferably integral with said fixing means (141, 142). Device (100) according to any one of the preceding claims, in which said fixing means (141, 142) and / or said recording means (155, 156) are double, being provided in correspondence with two distinct portions of the device itself . Device (100) according to the preceding claim, wherein said fixing means (141, 142) and / or said recording means (155, 156) are arranged at or near two opposite longitudinal ends of said main body of retention (103). Device (100) according to any one of the preceding claims, wherein said main retention body (103), fastening means (141, 142), support means (150) and / or recording means (155, 156) they are rigidly connected or connectable, and preferably integral, with each other. Device (110) according to any one of the preceding claims, comprising a portion that forms a prosthetic element (111), preferably an articular element. 23. Device (110) according to the preceding claim, wherein said prosthetic element (111) is fixed to, and preferably integral with, said main retention body (103) and preferably arranged at one end thereof. 24. Assembly for the reconstruction of bone structures, for use in particular in the mandibular or maxillary field, comprising a reconstruction device (100) according to any one of the preceding claims and a reconstructive material (500) fixed or fixable to said support means (150) ). 25. Assembly according to the preceding claim, wherein said reconstructive material integrates stem cells.