CN109730812B - Focal cartilage defect prosthesis - Google Patents
Focal cartilage defect prosthesis Download PDFInfo
- Publication number
- CN109730812B CN109730812B CN201910096056.4A CN201910096056A CN109730812B CN 109730812 B CN109730812 B CN 109730812B CN 201910096056 A CN201910096056 A CN 201910096056A CN 109730812 B CN109730812 B CN 109730812B
- Authority
- CN
- China
- Prior art keywords
- layer
- cartilage
- defect
- fixing
- fixed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Abstract
The invention relates to a focal cartilage defect prosthesis, which belongs to the technical field of cartilage repair prostheses and consists of a body and fixing nails, wherein the body has a shape matched with the shapes of an inner cavity of a cartilage defect and a defect area and has the same or similar physical characteristics with the cartilage defect; one end of the fixing nail is fixed with the body, and the other end of the fixing nail extends out of the body to be fixed with subchondral bone of the defect inner cavity. The invention produces the prosthesis, does not need cell transplantation and proliferation, completes the whole operation at one time, has short time, high efficiency and high precision and accuracy, solves the problems of long function recovery time and reoperation risk in the prior art, and has higher practical value.
Description
Technical Field
The invention relates to the technical field of cartilage repair prostheses, in particular to a prosthesis for repairing joint functions at a joint cartilage defect.
Background
The absence of blood vessels in articular cartilage, the inability of chondrocytes to migrate, the inability of mature chondrocytes to proliferate and alter the manner of synthesis limit the self-repair capabilities of cartilage. Therefore, once a cartilage defect occurs, the cartilage defect is basically incapable of self-repairing, and needs to be repaired by implanting a cartilage scaffold through external surgery.
Articular cartilage defects are common in clinic, more than 60% of patients with knee arthroscopic surgery are accompanied by cartilage defects according to statistics, wherein 42% of patients are focal hyaline cartilage defects, namely the depth of the defects does not exceed a calcified cartilage layer, and the area of the defects is 2-4 cm 2. Since hyaline cartilage has no blood vessels, nerves and lymphatic system, the natural repair ability is low, and defects with a diameter of more than 4mm can hardly be completely repaired. If not treated in time, the injury will continue to worsen and cause arthritis with painful, swollen joints and deformity.
Aiming at the cartilage defects, the traditional treatment strategy is to ooze bone marrow blood by adopting a microfracture method in the operation, proliferate mesenchymal stem cells in blood clots and repair the cartilage defects, but finally form fibrocartilage with poor wear resistance.
With the rapid development of tissue engineering technology, autologous chondrocyte transplantation technology is gradually popularized and applied in clinic, but the technology needs to perform in-vitro amplification on autologous chondrocytes, then implant the autologous chondrocytes through secondary operation, and has long recovery time; since in vitro culture is difficult to simulate in vivo microenvironment, especially lacking in monitoring of the body's immune system, the implanted chondrocytes often have undergone phenotypic changes, and the resulting repaired tissue, structurally or compositionally, differs essentially from native cartilage and is difficult to ensure long-term effectiveness of its treatment.
Disclosure of Invention
In view of the above, the present invention provides a focal cartilage defect prosthesis, which can be produced by personalized 3D printing or processing, and directly perform an operation without cell proliferation, and has a short operation time and high efficiency, so as to solve the problems of long function recovery time and risk of re-operation in the prior art.
The invention is realized by the following technical scheme:
a focal cartilage defect prosthesis consists of a body and fixing nails,
the body has the shape matched with the shape of the cartilage defect inner cavity and the defect area, and has the same or similar physical characteristics with the cartilage defect;
one end of the fixing nail is fixed with the body, and the other end of the fixing nail extends out of the body to be fixed with subchondral bone of the defect inner cavity.
Further, the body includes a cartilage layer and a fixation layer.
Further, the body comprises a cartilage layer, a fixing layer and a calcification layer arranged between the cartilage layer and the fixing layer.
Furthermore, the cartilage layer is made of polyethylene or a mixture of collagen and proteoglycan, has mechanical properties and friction coefficient similar to those of the cartilage around the defect, and does not generate stress shielding or over compression when bearing load.
Further, the fixed layer is a porous structure or a compact structure made of titanium alloy, tantalum alloy or cobalt-chromium-molybdenum alloy.
Further, the calcification layer and the fixing nails are compact structures made of titanium alloy or tantalum alloy or cobalt-chromium-molybdenum alloy.
Further, the thickness of the cartilage layer is consistent with that of the defect cartilage, and the thickness of the calcified layer is consistent with that of the calcified cartilage layer.
Furthermore, the thickness of the porous structure is 1.5-3mm, the pore diameter is 400-600um, the wire diameter is 0.35-0.65mm, and the porosity is 75% -85%.
Furthermore, one end of the fixing nail is fixed with the fixing layer, and the other end of the fixing nail extends out of the fixing layer.
Furthermore, one end of the fixing nail is fixed with the calcification layer, and the other end extends out of the fixing layer.
Furthermore, the calcified layer, the cartilage layer and the fixed layer are connected by special-shaped surfaces.
Further, the cross section of the fixing nail is a regular polygon.
Furthermore, the diameter of the circumscribed circle of the regular polygon of the fixing nail is 2-4mm, and the length of the circumscribed circle extending out of the body is 2-5 mm.
The invention has the beneficial effects that:
the body has the shape matched with the shapes of the cartilage defect inner cavity and the defect area, so that the prosthesis and the cartilage of the human body are fixedly combined to form a structural whole, and the structural whole has the physical characteristics same as or similar to those of the defect cartilage, so that the joint defect part can bear certain load impact, and further the joint function is recovered; the invention also fixes the body by the fixing nail, so that the body is accurately positioned, the joint function is stable and reliable, and the problem of uncertainty in the prior art is avoided.
In a word, the prosthesis is commercialized, can be customized according to different defect conditions, has high matching degree with the defect, does not need cell transplantation and proliferation, is completed in one step, has short time, high efficiency and high precision and accuracy, solves the problems of long function recovery time and uncertainty in need of secondary operation in the prior art, and has higher practical value.
Drawings
FIG. 1 is a schematic structural view of a cartilage defect;
FIG. 2 is a schematic structural diagram of a first embodiment of the present invention;
FIG. 3 is a schematic view of the structure of FIG. 1 with two staples;
FIG. 4 is a front view of the staple;
FIG. 5 is a osteochondral structure model proposed by the present inventors;
FIG. 6 is a schematic structural diagram of a second embodiment of the present invention;
fig. 7 is a schematic structural view of fig. 6 with two fixing nails.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
In the above description of the present invention, it should be noted that the terms "one side", "the other side" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships that the products of the present invention are conventionally placed in use, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the device or the element to which the present invention is directed must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.
Further, the term "identical" and the like do not mean that the components are absolutely required to be identical, but may have slight differences. The term "perpendicular" merely means that the positional relationship between the components is more perpendicular than "parallel", and does not mean that the structure must be perfectly perpendicular, but may be slightly inclined.
FIG. 1 is a schematic diagram of articular cartilage defect, the prior art basically adopts a scheme of cell transplantation and proliferation for repair, and has the problems of long joint function recovery time and uncertain need of re-operation, and the following is an improved scheme proposed by the inventor for repair of cartilage defect.
The first embodiment is as follows:
as shown in fig. 2, a focal cartilage defect prosthesis is composed of a body 1 and a fixing nail 2, both of which can be directly processed without cell transplantation and proliferation, and can be customized individually, specifically:
the body is a double-layer structure consisting of a cartilage layer 3 and a fixed layer 4;
the material of the cartilage layer is not limited as long as the cartilage layer has mechanical properties similar to those of the cartilage around the defect, a certain viscoelasticity and compression modulus are ensured, stress shielding or excessive compression cannot be generated during bearing, the cartilage layer can be made of polyethylene or a material similar to the physical properties of the polyethylene, or a mixture of collagen and proteoglycan,
the internal structure and materials of the fastening layer and the fastening nail are not limited as long as: the fixed layer can bear physical impact of various joint movements; and under the constraint of the fixing nail, the prosthesis can be always kept at the cartilage defect position in various joint activities.
Preferably, the fixing layer and the fixing nails are of a compact structure, and the compact structure has stronger structural strength relative to a porous structure and can bear various joint movements; meanwhile, the compact structure can be made of metal materials or non-metal materials, and the metal materials are made of titanium alloy or tantalum alloy or cobalt-chromium-molybdenum alloy with similar physical properties with the titanium alloy.
One end of the fixing nail is fixed with the body, and the other end of the fixing nail extends out of the body to be fixed with subchondral bone of the defect inner cavity, so that the body is fixed in the defect inner cavity;
in the scheme:
because the prosthesis is commercialized, cell transplantation and proliferation are not needed, the whole operation is completed at one time, the time is short, and the efficiency is high;
the body has the shape matched with the shapes of the cartilage defect inner cavity and the defect area, and the body is attached to the defect inner cavity and is matched with the shape of the defect area, so that the prosthesis and the cartilage of a human body form a complete structural whole, the prosthesis and the cartilage of the human body jointly bear the load impact of joint movement, and the joint function repair can be realized.
Particularly, this embodiment still fixes the location of body through the staple, makes the location of body accurate, makes the joint function reliable and stable, avoids the uncertain problem of prior art.
In this embodiment, the number of the fixing nails is not fixed, and two or more fixing nails may be selected in practical use. Fig. 3 shows the case of using two. However, the number of the fixing nails is not too large, the problem of excessive positioning exists too much, the manufacturing cost is increased, and the number of the fixing nails is considered to be in the range of 1-4 by the inventor.
In this embodiment, the thickness of the cartilage layer is the same as the thickness of the defect cartilage, and the thickness of the fixation layer is the same as the thickness of the calcified cartilage layer. Thus, the total thickness of the prosthesis is consistent with the total depth of the defect part, and when the material characteristics of the prosthesis are consistent with those of the joint, the damaged joint filled with the prosthesis has the same or similar functional level with the normal joint.
In this embodiment, the shape of the fixing nail is a regular polygon. And processing a hole slightly smaller than the appearance of the fixing nail at the defect position, and knocking the fixing nail into the hole to form fixation. Because the fixing nail is in a regular polygon shape, the fixing nail can be prevented from rotating in the hole and loosening.
Meanwhile, the number of the fixing nail sides is not limited, and can be 4, 5, 6, 7 …, and the embodiment is preferably 6. As shown in fig. 4.
It should be noted that the size and length of the staple of the present embodiment are not limited. However, it is known that if the staple is too short or too thin, the fastening force is not sufficient to cause bending or slipping, but the staple cannot be too thick or too long due to the restriction of the lesion area. After years of practice, the inventor considers that the better condition is that: the diameter of the circumscribed circle of the regular polygon of the fixing nail is 2-4mm, and the length of the fixing nail extending out of the fixing layer is 2-5mm, so that the fixing nail has higher adaptability.
In this embodiment, the body and the fixing nail may be manufactured by 3D printing, or by machining a blank of the prosthesis, then by numerical control machining, and finally by machining the shape of the prosthesis. Because the fixed layer plays the supporting role, the staple plays spacing fixed action, consequently, both set up to compact structure, have certain structural strength, can bear joint motion's load impact.
The dense structure of this example is a solid structure without pores or network.
In this embodiment, in order to improve the fixing effect, the fixing layer and the cartilage layer are connected by a special-shaped surface. As shown in fig. 2, the bonding surface between the fixing layer and the cartilage layer is wavy, and the materials are mutually occluded through the wavy bonding surface with the wavy height, so that the bonding area is larger, the occlusion force is stronger, and the fixation is firmer.
On the basis of the above scheme, the inventor combines the previously proposed osteochondral model of "three-layer structure, two-boundary line", as shown in fig. 5, and particularly proposes the following more preferable scheme:
example two:
as shown in fig. 6 and 7, different from the first embodiment, the body of the present embodiment has a three-layer structure, specifically including a cartilage layer 3, a calcification layer 5 and a fixing layer 4, the calcification layer at this time is a dense layer, which plays a role in connecting the cartilage layer and the fixing layer, and supports the fixing layer, the fixing layer is a porous network structure, the porous network structure easily forms a growth chamber, chondrocytes can enter the growth chamber to grow and proliferate, so that the body and articular cartilage are embedded with each other, and the fixing effect is better.
In this embodiment, in order to improve the fixing effect, the calcified layer, the cartilage layer and the fixing layer are connected by a special-shaped surface, which may be wave-shaped, tooth-shaped or square. The shape of the junction surface between the calcified layer and the cartilage layer and the shape of the junction surface between the calcified layer and the cartilage layer may be the same or different, but the height H1 of the junction surface between the calcified layer and the cartilage layer is lower than the height H2 of the junction surface between the calcified layer and the cartilage layer, which is beneficial to the integration with host bones, as shown in fig. 6, the calcified layer and the cartilage layer are in wave-shaped combination, and the calcified layer and the fixed layer are in tooth form, so that the combination of the calcified layer, the fixed layer and the cartilage layer is more consistent with the actual situation.
The related research results of the invention show that: the thickness of the porous structure is 1.5-3mm, the pore diameter is 400-600um, the silk diameter is 0.35-0.65mm, the porosity is 75-85%, and the proliferation capacity of the cells is better.
In this embodiment, the thickness of the cartilage layer is the same as the thickness of the defective cartilage, and the thickness of the calcified layer is the same as the thickness of the calcified cartilage layer. Therefore, the three-layer structure of the embodiment is matched with the osteochondral model with the three-layer structure and two boundary lines provided by the inventor, and the actual situation of the cartilage is simulated more truly.
Finally, the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting, although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all of them should be covered in the claims of the present invention.
Claims (4)
1. A focal cartilage defect prosthesis is characterized in that: is composed of a body and a fixed nail,
the body has the shape matched with the shape of the cartilage defect inner cavity and the defect area, and has the same or similar physical characteristics with the cartilage defect;
one end of the fixing nail is fixed with the body, and the other end of the fixing nail extends out of the body and is fixed with subchondral bone of the defect inner cavity;
the body comprises a cartilage layer, a fixing layer and a calcification layer arranged between the cartilage layer and the fixing layer;
the cartilage layer is made of polyethylene or a mixture of collagen and proteoglycan, has mechanical properties and friction coefficient similar to those of cartilage around the defect, and cannot generate stress shielding or over compression when bearing load;
the fixed layer is of a porous structure made of tantalum alloy; the thickness of the porous structure is 1.5-3mm, the pore diameter is 400-600 mu m, the wire diameter is 0.35-0.65mm, and the porosity is 75-85%;
the body and the fixing nails are manufactured in a 3D printing mode;
the calcified layer, the cartilage layer and the fixed layer are connected by special-shaped surfaces; the height of the joint surface between the calcification layer and the cartilage layer is lower than that between the calcification layer and the fixing layer;
the cross section of the fixing nail is a regular polygon, the diameter of a circumscribed circle of the regular polygon of the fixing nail is 2-4mm, and the length of the circumscribed circle extending out of the body is 2-5 mm.
2. The focal cartilage defect restoration according to claim 1, wherein: the calcification layer and the fixing nail are compact structures made of titanium alloy or tantalum alloy or cobalt-chromium-molybdenum alloy.
3. The focal cartilage defect restoration according to claim 1, wherein: the thickness of the cartilage layer is consistent with that of the defect cartilage, and the thickness of the calcified layer is consistent with that of the calcified cartilage layer.
4. The focal cartilage defect restoration according to claim 1, wherein: one end of the fixing nail is fixed with the calcification layer, and the other end extends out of the fixing layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910096056.4A CN109730812B (en) | 2019-01-31 | 2019-01-31 | Focal cartilage defect prosthesis |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910096056.4A CN109730812B (en) | 2019-01-31 | 2019-01-31 | Focal cartilage defect prosthesis |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109730812A CN109730812A (en) | 2019-05-10 |
| CN109730812B true CN109730812B (en) | 2022-02-08 |
Family
ID=66366926
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910096056.4A Active CN109730812B (en) | 2019-01-31 | 2019-01-31 | Focal cartilage defect prosthesis |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109730812B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117398220B (en) * | 2023-12-13 | 2024-04-02 | 北京爱康宜诚医疗器材有限公司 | Cartilage repair prosthesis |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101020083A (en) * | 2007-03-08 | 2007-08-22 | 中国人民解放军第三军医大学第一附属医院 | Integral engineering rack of interface osteochondro tissue with bionic function |
| CN101019786A (en) * | 2006-09-27 | 2007-08-22 | 四川大学华西医院 | Compound partial femoral head surface prosthesis |
| CN101417151A (en) * | 2008-07-10 | 2009-04-29 | 中国人民解放军第三军医大学第一附属医院 | Biology source type calcified-layer containing cartilage tissue engineer bracket |
| CN101954121A (en) * | 2010-09-30 | 2011-01-26 | 中国人民解放军第四军医大学 | Cartilage deficiency prosthesis, preparation method thereof and integrated cartilage-bone repair material |
| CN102014800A (en) * | 2008-02-28 | 2011-04-13 | 比奥波利公司 | Partial joint resurfacing implant, instrumentation, and method |
| CN102274548A (en) * | 2011-08-26 | 2011-12-14 | 中国人民解放军军事医学科学院卫生装备研究所 | Bone-cartilage repair gradient active scaffold material and preparation method and use thereof |
| CN102526809A (en) * | 2012-03-06 | 2012-07-04 | 四川大学华西医院 | Stent for osteochondral defect repair and preparation method thereof |
| CN103463676A (en) * | 2013-08-14 | 2013-12-25 | 西安交通大学 | Bionic bone/cartilage composite scaffold and preparation technology and fixing method thereof |
| CN104434342A (en) * | 2014-12-09 | 2015-03-25 | 张海宁 | Medical planted osteochondral prosthesis system |
| CN105534619A (en) * | 2016-01-28 | 2016-05-04 | 江苏奥康尼医疗科技发展有限公司 | Cartilage repair and compensation prosthesis |
| CN108404214A (en) * | 2018-06-01 | 2018-08-17 | 上海贝奥路生物材料有限公司 | A kind of bionical osteochondral composites and preparation method thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020183858A1 (en) * | 2001-06-05 | 2002-12-05 | Contiliano Joseph H. | Attachment of absorbable tissue scaffolds to scaffold fixation devices |
| US8187326B2 (en) * | 2002-05-22 | 2012-05-29 | Advanced Technologies And Regenerative Medicine, Llc. | Attachment of absorbable tissue scaffolds to fixation devices |
-
2019
- 2019-01-31 CN CN201910096056.4A patent/CN109730812B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101019786A (en) * | 2006-09-27 | 2007-08-22 | 四川大学华西医院 | Compound partial femoral head surface prosthesis |
| CN101020083A (en) * | 2007-03-08 | 2007-08-22 | 中国人民解放军第三军医大学第一附属医院 | Integral engineering rack of interface osteochondro tissue with bionic function |
| CN102014800A (en) * | 2008-02-28 | 2011-04-13 | 比奥波利公司 | Partial joint resurfacing implant, instrumentation, and method |
| CN101417151A (en) * | 2008-07-10 | 2009-04-29 | 中国人民解放军第三军医大学第一附属医院 | Biology source type calcified-layer containing cartilage tissue engineer bracket |
| CN101954121A (en) * | 2010-09-30 | 2011-01-26 | 中国人民解放军第四军医大学 | Cartilage deficiency prosthesis, preparation method thereof and integrated cartilage-bone repair material |
| CN102274548A (en) * | 2011-08-26 | 2011-12-14 | 中国人民解放军军事医学科学院卫生装备研究所 | Bone-cartilage repair gradient active scaffold material and preparation method and use thereof |
| CN102526809A (en) * | 2012-03-06 | 2012-07-04 | 四川大学华西医院 | Stent for osteochondral defect repair and preparation method thereof |
| CN103463676A (en) * | 2013-08-14 | 2013-12-25 | 西安交通大学 | Bionic bone/cartilage composite scaffold and preparation technology and fixing method thereof |
| CN104434342A (en) * | 2014-12-09 | 2015-03-25 | 张海宁 | Medical planted osteochondral prosthesis system |
| CN105534619A (en) * | 2016-01-28 | 2016-05-04 | 江苏奥康尼医疗科技发展有限公司 | Cartilage repair and compensation prosthesis |
| CN108404214A (en) * | 2018-06-01 | 2018-08-17 | 上海贝奥路生物材料有限公司 | A kind of bionical osteochondral composites and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109730812A (en) | 2019-05-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2338530B1 (en) | Hybrid polymer/metal plug for treating chondral defects | |
| US7572291B2 (en) | Osteochondral repair assembly including retracting spacer, kit and method | |
| US4880429A (en) | Prosthetic meniscus | |
| AU2009221838B2 (en) | Implants and methods of use | |
| US8556972B2 (en) | Monolithic orthopedic implant with an articular finished surface | |
| US6312467B1 (en) | Method of restructuring bone | |
| US20110257753A1 (en) | Implant having a convex surface surrounding a concave articular surface | |
| US9241808B2 (en) | Auxetic prosthetic implant | |
| US9289302B2 (en) | Mosaicplasty constructs | |
| CN109481098B (en) | toe joint prosthesis | |
| EP1670396A1 (en) | Multipiece allograft implant | |
| AU2010286660A1 (en) | Trochlear implants and methods of use | |
| CN101019786A (en) | Compound partial femoral head surface prosthesis | |
| Levine et al. | Porous metals in orthopedic applications–a review | |
| CN109730812B (en) | Focal cartilage defect prosthesis | |
| WO2012003037A9 (en) | Convex concave implant | |
| CN201977964U (en) | Artificial intervertebral disc | |
| CN214712937U (en) | Total hip replacement prosthesis | |
| CN209661886U (en) | Toe joint prosthese | |
| CN211131550U (en) | Femoral implant | |
| CN209808647U (en) | Artificial knee joint | |
| CN112603606A (en) | Knee joint cartilage prosthesis for local replacement | |
| CN214387788U (en) | Knee joint bone prosthesis | |
| Park et al. | Hard tissue replacement II: joints and teeth | |
| Dong et al. | Research progress on repair of osteochondral defects |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |