Patent Application
20170296242
The invention concerns an orthognatic bone joining implant (also referred to as a positioning implant) for an osteotomy application/joining of a first bone section with a second bone section or several bone sections of a mammal bone/bone of a mammal with a first attachment area displaying several holes for fastening elements, prepared for attachment to the first bone area, and a second attachment area linked to the first attachment area, with the second attachment area also displaying several holes for fastening elements, also prepared for attachment to the second bone section. Especially in the case of a bisected lower jaw, for instance with a crowding of the lower jaw, there are several bone sections to which the first bone section will be joined. A mammal bone/bone of a mammal is defined as an especially hard, skeleton growing supporting tissue of a vertebrate, that is to say, such a structure made of bone tissue. This includes in particular such bones as the fibula and tibia, but also cranial bones.
Bone joining implants in conformity with their kind are already known at the current technology status. In this context, WO 2014/090964 A2 for instance reveals a guide, together with a procedure for its configuration. The implant as well as the guide are intended for osteotomy applications at a patient's maxilla and may be designed as a kit. The three dimensional models of the pre and post-operative anatomy are used to define the attachment areas for the guide and the implant. Those attachment areas will then further be used to define the structure of the implant as well as the guide. The technology status is further known from EP 2 698 122 A1 and WO 2011/136898 A1.
Those designs known from the technology status, however, for the most part have the disadvantage that two separate elements must be used for separating the mammal bones that are to be corrected and then joined again, such as, for example a maxilla or mandible. Preferably, the cutting of the mammal bone is performed through a sawing procedure, with a template-like tool guidance, and the joining of the two formerly separated bone sections in the desired position is done with an implant. Thus, in the past, any osteotomy applications always required the manufacture of a user defined tool guidance as well as a user defined positioning implant. This resulted in a relatively extensive manufacture of the elements used for the osteotomy applications and therefore relatively high surgery cost.
Therefore, the task of this invention is to remedy these disadvantages known from the technology status and, in particular, to provide a bone joining implant that will further reduce the extent of an osteotomy treatment, while maintaining at the same time a patient specific/individualized adjustment of the bone joining implant.
The solution provided by the invention is the formation of a (first) separating tool guidance contour between the first and second attachment area, defining a (first) cutting line. A position between the first and the second attachment area means any (spatial) position, viewed in its spatial extension along the mammal bone, located between the first and second attachment areas. Thus, the separating tool guidance contour is located between a side of the first attachment area, facing the second attachment area, and a side of the second attachment area, facing the first attachment area.
This design permits the use of the bone joining implant not only as a positioning implant but also as a separating template for the previous separation of the two sections of the mammal bone. This allows for an especially cost efficient correction of the relevant malformation of the mammal bone. It should be pointed out that a further advantage of using the same implant for cutting and then joining is, in particular, the avoidance of any manufacturing tolerances between the tool guidance,
previously manufactured separately, and the positioning implant. After joining, the two bone sections are then located in relation to each other with a notably higher precision, corresponding to the previously calculated target position, which will in turn foster the healing process of the mammal bone.
Any further design advantages are being claimed in the sub-claims and described in more detail below.
The bar design of the separating tool guidance contour provides an additional advantage. This creates a stabile support of the cutting tool, such as a saw/buzz saw, on the separating tool guidance contour, in order to cut the two bone sections along the separating line/osteotomy line.
A further advantage is provided by a design directly linking the separating tool guidance contour with a bridge between the first attachment area and/or the second attachment area. This creates an especially compact structure of the bone joining implant.
If the separating tool guidance contour is designed with an interior edge of a frame structure located between the first and the second attachment area, this serves the purpose of placing the separating tool guidance contour in a particularly dimensionally stable section of the bone joining implant whose structure cannot simply be altered by the cutting operation.
If the (first and second) attachment areas and the separating tool guidance contour are designed/linked integrally/in one part, the bone joining implant will be even more stable. This further enhances the formal stability between the attachment areas and the separating tool guidance contour.
A further advantage is provided by manufacturing the bone joining implant from a biocompatible and/or biodegradable substance/made entirely from that substance. This will allow for a particularly efficient use of the bone joining implant.
In this context, manufacture of the bone joining implant from a metal substance, preferably a titanium substance, will also afford a particular advantage. Preferably, the titanium substance will receive heat treatment. This will create a particularly dimensionally stable bone joining implant.
It is advisable to create an additional/second separating tool guidance contour between the second attachment area and an additional third attachment area, defining a (second) separating line, with the third attachment area again displaying several holes to receive the fastening elements and prepared for attachment to the first bone section. Thus, the link between the two bone sections will be even more stable, with both bone sections being linked to each other in a secured position. In this context, the second separating tool guidance contour will preferably be designed in the same way as the first separating tool guidance contour.
A further advantage would be to prepare the bone joining implant for joining the first bone section with the second bone section of a maxilla bone/maxilla or a mandible bone/mandible. Thus, the bone joining implant will be particularly efficient.
The invention further concerns a procedure for the individualized manufacture of the bone implant based on at least one of the previously described designs, comprising the following steps, preferably in a timely sequence:
This will allow for a particularly effective manufacture of the bone joining implant.
The invention further concerns a procedure for the treatment of a mammal bone, preferably human, using a bone joining implant in accordance with one of the previously described designs, comprising the following steps:
This allows for a particularly effective treatment procedure.
In the following, the invention is further described based on diagrams, showing in
Those figures are solely schematic in nature and are exclusively designed for a better understanding of the invention. Identical elements are marked with the identical reference.
In
Clearly visible in
11, 13. The third attachment area 16 is essentially formed similarly to the first attachment area 6, also displaying several holes for fastening elements that are hereafter referred to as the third set of holes for receiving fastening elements 5c. As described below in more detail, this third set of holes for receiving fastening elements 5c is designed for the attachment to the first bone section 2. The first attachment area 6 as well as the third attachment area 16 each display two groups of first and third holes for receiving fastening elements 5a, 5c, respectively, placed in a triangular formation relative to each other.
The first set of holes for receiving fastening elements 5a is placed on a first bridge 10, assigned to the first attachment area 6, essentially placed horizontally, attached to the mammal bone 4. Thus, the first attachment area 6 forms the first bridge 10, with a bar shaped design and linking both groups comprising the first set of holes for receiving fastening elements 5a (each with three first holes for receiving fastening elements) to each other. Two bridges 21, with an essentially vertical position relative to the first bridge 10, are then also linked with the first attachment area 6. Each of the bridges 21 is fitted to the first attachment area 6 within the area of a hole for fastening elements 5a. The bridges 21 are linking the first attachment area 6 or the first bridge 10 to the second bridge 11, also bar shaped and formed at the second attachment area 7, essentially running parallel to the first bridge 10. Both bridges 21 as well as the second bridge 11 associated with the second attachment area 7, together with the first bridge 10 associated with the first attachment area 6, essentially form a diamond shaped/rectangular frame structure 15a.
Similarly, the third attachment area 16 is linked to the second attachment area 7. The third set of holes for fastening elements 5c is placed on a third bridge 12, allocated to a third attachment area 16, essentially placed in a horizontal position, attached to the mammal bone 4. Thus, the third attachment area 16 forms the third bridge 12, bar shaped, and linking both groups
of the third set of holes for fastening elements 5c (each with three holes for receiving fastening elements of the third set 5c) to each other. Two bridges 21, with an essentially vertical position relative to the third bridge 12, are then also linked with the third attachment area 16. Each of the bridges 21 is fitted to the third attachment area 16 within the area of a hole for fastening elements 5c. The bridges 21 are linking the third attachment area 16 or the third bridge 12 to the fourth bridge 13, also bar shaped and formed at the second attachment area 7, essentially running parallel to the third bridge 12. Both bridges 21 as well as the fourth bridge 13 associated with the second attachment area 7, together with the third bridge 12 associated with the third attachment area 16, essentially form a second diamond shaped/rectangular frame structure 15b.
In this design, the first frame structure 15a varies slightly from the second frame structure 15b. The second frame structure 15b is formed differently in so far as the distance between the third and fourth bridge 12, 13 is greater than the distance between the first and second bridge 10, 11.
The third set of holes for fastening elements is formed similarly to the first and second set of holes for fastening elements 5a, 5b. The holes for receiving fastening elements 5a, 5b, 5c all provide reception for fastening elements in the usual manner, shaped as bone screws, with each of the holes for fastening elements 5a, 5b, 5c displaying a conic screw head fitting area 20 on the side facing away from the bone sections 2, 3, respectively. With the bone joining implant 1 attached to both bone sections 2, 3, the screw heads of the bone screws will then be completely sunk into the holes for fastening elements 5a, 5b, 5c.
As clearly shown by the interaction of
In this design, an interior edge, namely, a first interior edge 14a of the first bridge 10, directly forms a first separating tool guidance contour 9 prepared to serve as a guiding track for a separating tool, namely, a sawing tool/buzz saw. The first separating tool guidance contour 9 remodels a first separating line 8 to be created, in the mammal bone 4. Alternatively or additionally, it is possible to design the (second) interior edge 14b of the second bridge 11 as a first separating tool guidance contour 9. The first and second interior edges 14a, 14b, respectively, are the lateral edges of the bridges 10, 11, facing each other.
In addition, the (third) interior edge 14c of the third bridge 12 is also designed as a separating tool guidance contour, that is as the second separating tool guidance contour 18. The second separating tool guidance contour 18 is here also used as a guiding track for a separating tool, namely a sawing tool/buzz saw for separating the first bone section 2 from the second bone section 3. The second separating tool guidance contour 18 remodels a first separating line 17 to be created, in the mammal bone 4. Alternatively or additionally, it is possible to design the (fourth) interior edge 14d of the fourth bridge 13 as a second separating tool guidance contour 18. The third and fourth interior edges 14c, 14d, respectively, are the lateral edges of the bridges 10, 11, facing each other.
The second and fourth bridges 10, 11 are also an integral component of the principal bridge 22 linking both frame structures 15a, 15b in a dimensionally stable, wing shaped position. It should be pointed out that the principal bridge 22, based on another design, located in a median position between the frame structures 15a, 15b, is provided with a resealing mechanism, so that the frame structures 15a, 15b can be attached to bone sections 2, 3 independently from each other and can then again be linked to each other through that mechanism in a dimensionally stable position.
Through its design as an implant, the bone joining implant is formed/made from a biocompatible substance, namely a hardened titanium substance. In addition or alternatively, the bone joining implant 1 can be manufactured, in whole or in part, from a biodegradable substance/be biodegradable.
In connection with
This mammal bone 4 already shows a malformation of a maxilla/maxilla bone 19 that is to be remedied by dysgnathic, separation surgery/osteotomy treatment. Based on this imaginary 3D model of the existing condition, a 3D target model of the maxilla/the mammal bone 4 will then be created, defining a cutting line 8 or 17, respectively, on the imaginary 3D model of the existing condition for each of the first and third attachment areas 6, 16. The cutting lines 8, 17, placed on the 3D model of the existing condition, are then each assigned one of the separating tool guidance contours 9, 18; that is, they will each be fitted to one of the separating tool guidance contours 9, 18 in accordance with the cutting lines 8, 17. After establishing those two cutting lines 8, 17, an imaginary separation of bone sections 2, 3 will be performed and they will be moved to the desired relative position, in relation to each other, eventually creating an imaginary 3D target model (calculated in a second data set) in
Also, in connection with
In other words, the concept of the invention is to join a sawing template with a patient-specific orthognatic implant
to create a combination sawing and positioning implant. It is particularly beneficial that any poisoning aids such as splints, navigation devices, marking screws and milling lines can be eliminated. No additional drilling template is required. In addition, precision of the planned implementation and surgical intervention will be enhanced, which in turn alleviates bacterial exposure by eliminating any additional potential germ carriers. The surgical procedure will be facilitated by reducing the individual steps of surgical intervention. Also, the operating time will be reduced by eliminating any additional exchange of instruments and by reduction of the individual steps. This will ultimately provide for a more cost efficient production due to reduction of production steps.
Based on the invention, the design of the bone joining implant 1 comprises two bridges per side, horizontally aligned (10, 11; 12, 13), located in the right and left maxillary sinus wall, respectively, extending from the crista zygomaticoalveolaris to each lateral side of the foramen piriformis. Those two bridges (10, 11; 12, 13), through the in between space/slot thus created, form a guidance that corresponds to a sawing template. The in between space can also run parallel if a bone resection is to be performed. In that case, the lower edge (14a; 14c) of the upper bridge, and the upper edge of the lower bridge (14b; 14d) will serve as a guidance for the osteotomy. If necessary, drilling holes may be placed on the bridges (10, 11; 12, 13) in order to create additional fixation points. The horizontally aligned bridges (10, 11; 12, 13) are attached to four vertically aligned bridges 21, representing a link between the upper and lower pair of bridges (10, 11; 12, 13). The intended shifting information will be encrypted in this area by bending. Both horizontally aligned bridges (10, 11; 12, 13) on the left and right are each linked, in the outer (lateral) area, to a vertical bridge 21, to obtain sufficient stability in this area. If necessary, they can be elongated towards the cheek bone in order to obtain additional fixation points with osteosynthesis screws (bone screws). In a paranasal position on both sides, there are vertically aligned bridges with drilling holes for additional fixation. Below the spina nasales, the right and left sides are linked by a horizontally aligned bridge (10, 11; 12, 13). This link may also be created in situ in the spina nasales area by anchoring or using the lock and key model during surgery so that a large implant can initially be disassembled into smaller individual parts. This type of implant may also be provided for several jaw sections, such as the three part LeFort I osteotomy.
While
| Number | Date | Country | Kind |
|---|---|---|---|
| 102015107484 | May 2015 | DE | national |
| Number | Date | Country | |
|---|---|---|---|
| 20160331427 A1 | Nov 2016 | US |
