CA1142430A - Bone substitute material and its use - Google Patents
Bone substitute material and its useInfo
- Publication number
- CA1142430A CA1142430A CA000341820A CA341820A CA1142430A CA 1142430 A CA1142430 A CA 1142430A CA 000341820 A CA000341820 A CA 000341820A CA 341820 A CA341820 A CA 341820A CA 1142430 A CA1142430 A CA 1142430A
- Authority
- CA
- Canada
- Prior art keywords
- bone
- bones
- water
- product
- rinsing
- 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.)
- Expired
Links
- 239000000463 material Substances 0.000 title claims abstract description 61
- 239000000316 bone substitute Substances 0.000 title claims abstract description 17
- 210000000988 bone and bone Anatomy 0.000 claims abstract description 64
- 238000000034 method Methods 0.000 claims abstract description 34
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 22
- 102000008186 Collagen Human genes 0.000 claims abstract description 11
- 108010035532 Collagen Proteins 0.000 claims abstract description 11
- 229920001436 collagen Polymers 0.000 claims abstract description 11
- 229910052500 inorganic mineral Inorganic materials 0.000 claims abstract description 7
- 239000011707 mineral Substances 0.000 claims abstract description 7
- 210000002082 fibula Anatomy 0.000 claims abstract description 5
- 239000003960 organic solvent Substances 0.000 claims abstract description 5
- 150000003839 salts Chemical class 0.000 claims abstract description 5
- 102000004169 proteins and genes Human genes 0.000 claims description 8
- 108090000623 proteins and genes Proteins 0.000 claims description 8
- 102000055006 Calcitonin Human genes 0.000 claims description 7
- 108060001064 Calcitonin Proteins 0.000 claims description 7
- 238000005238 degreasing Methods 0.000 claims description 7
- BBBFJLBPOGFECG-VJVYQDLKSA-N calcitonin Chemical compound N([C@H](C(=O)N[C@@H](CC(C)C)C(=O)NCC(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CO)C(=O)N[C@@H](CCC(N)=O)C(=O)N[C@@H](CCC(O)=O)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CC=1NC=NC=1)C(=O)N[C@@H](CCCCN)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CCC(N)=O)C(=O)N[C@@H]([C@@H](C)O)C(=O)N[C@@H](CC=1C=CC(O)=CC=1)C(=O)N1[C@@H](CCC1)C(=O)N[C@@H](CCCNC(N)=N)C(=O)N[C@@H]([C@@H](C)O)C(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H]([C@@H](C)O)C(=O)NCC(=O)N[C@@H](CO)C(=O)NCC(=O)N[C@@H]([C@@H](C)O)C(=O)N1[C@@H](CCC1)C(N)=O)C(C)C)C(=O)[C@@H]1CSSC[C@H](N)C(=O)N[C@@H](CO)C(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H](CC(C)C)C(=O)N[C@@H](CO)C(=O)N[C@@H]([C@@H](C)O)C(=O)N1 BBBFJLBPOGFECG-VJVYQDLKSA-N 0.000 claims description 6
- 229960004015 calcitonin Drugs 0.000 claims description 6
- 230000001954 sterilising effect Effects 0.000 claims description 6
- 241001465754 Metazoa Species 0.000 claims description 5
- 210000004369 blood Anatomy 0.000 claims description 5
- 239000008280 blood Substances 0.000 claims description 5
- 229940088597 hormone Drugs 0.000 claims description 4
- 239000005556 hormone Substances 0.000 claims description 4
- 239000000049 pigment Substances 0.000 claims description 3
- 239000007858 starting material Substances 0.000 claims description 3
- 239000008139 complexing agent Substances 0.000 claims description 2
- BBBFJLBPOGFECG-UHFFFAOYSA-N salmon calcitonin Chemical compound C=1N=CNC=1CC(C(=O)NC(CCCCN)C(=O)NC(CC(C)C)C(=O)NC(CCC(N)=O)C(=O)NC(C(C)O)C(=O)NC(CC=1C=CC(O)=CC=1)C(=O)N1C(CCC1)C(=O)NC(CCCNC(N)=N)C(=O)NC(C(C)O)C(=O)NC(CC(N)=O)C(=O)NC(C(C)O)C(=O)NCC(=O)NC(CO)C(=O)NCC(=O)NC(C(C)O)C(=O)N1C(CCC1)C(N)=O)NC(=O)C(CC(C)C)NC(=O)C(CCC(O)=O)NC(=O)C(CCC(N)=O)NC(=O)C(CO)NC(=O)C(CC(C)C)NC(=O)C(CCCCN)NC(=O)CNC(=O)C(CC(C)C)NC(=O)C(C(C)C)NC(=O)C1CSSCC(N)C(=O)NC(CO)C(=O)NC(CC(N)=O)C(=O)NC(CC(C)C)C(=O)NC(CO)C(=O)NC(C(C)O)C(=O)N1 BBBFJLBPOGFECG-UHFFFAOYSA-N 0.000 claims 1
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 12
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 8
- 238000002513 implantation Methods 0.000 description 7
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 6
- 239000000945 filler Substances 0.000 description 6
- 239000012153 distilled water Substances 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 238000004659 sterilization and disinfection Methods 0.000 description 4
- 238000002054 transplantation Methods 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 230000005855 radiation Effects 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- 238000001356 surgical procedure Methods 0.000 description 3
- 210000001519 tissue Anatomy 0.000 description 3
- ZGTMUACCHSMWAC-UHFFFAOYSA-L EDTA disodium salt (anhydrous) Chemical compound [Na+].[Na+].OC(=O)CN(CC([O-])=O)CCN(CC(O)=O)CC([O-])=O ZGTMUACCHSMWAC-UHFFFAOYSA-L 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 210000004204 blood vessel Anatomy 0.000 description 2
- 244000309466 calf Species 0.000 description 2
- 210000004027 cell Anatomy 0.000 description 2
- 230000006378 damage Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 230000001627 detrimental effect Effects 0.000 description 2
- 239000007943 implant Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000008399 tap water Substances 0.000 description 2
- 235000020679 tap water Nutrition 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 208000010392 Bone Fractures Diseases 0.000 description 1
- 208000017234 Bone cyst Diseases 0.000 description 1
- 208000018084 Bone neoplasm Diseases 0.000 description 1
- 241000283690 Bos taurus Species 0.000 description 1
- 241000700198 Cavia Species 0.000 description 1
- 101710184444 Complexin Proteins 0.000 description 1
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical class OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 1
- 241000283973 Oryctolagus cuniculus Species 0.000 description 1
- 241000700159 Rattus Species 0.000 description 1
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 1
- 208000027418 Wounds and injury Diseases 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 210000000601 blood cell Anatomy 0.000 description 1
- 210000002449 bone cell Anatomy 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 210000001612 chondrocyte Anatomy 0.000 description 1
- 210000001520 comb Anatomy 0.000 description 1
- 230000000536 complexating effect Effects 0.000 description 1
- 210000002808 connective tissue Anatomy 0.000 description 1
- 210000001608 connective tissue cell Anatomy 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002255 enzymatic effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 210000002950 fibroblast Anatomy 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000012634 fragment Substances 0.000 description 1
- 238000004108 freeze drying Methods 0.000 description 1
- 208000015181 infectious disease Diseases 0.000 description 1
- 208000014674 injury Diseases 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003387 muscular Effects 0.000 description 1
- 230000011164 ossification Effects 0.000 description 1
- 210000000963 osteoblast Anatomy 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 210000002435 tendon Anatomy 0.000 description 1
- 210000002303 tibia Anatomy 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07K—PEPTIDES
- C07K14/00—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof
- C07K14/435—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from animals; from humans
- C07K14/78—Connective tissue peptides, e.g. collagen, elastin, laminin, fibronectin, vitronectin or cold insoluble globulin [CIG]
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K38/00—Medicinal preparations containing peptides
- A61K38/16—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof
- A61K38/17—Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from animals; from humans
- A61K38/39—Connective tissue peptides, e.g. collagen, elastin, laminin, fibronectin, vitronectin, cold insoluble globulin [CIG]
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
- A61L27/36—Materials for grafts or prostheses or for coating grafts or prostheses containing ingredients of undetermined constitution or reaction products thereof, e.g. transplant tissue, natural bone, extracellular matrix
- A61L27/3641—Materials for grafts or prostheses or for coating grafts or prostheses containing ingredients of undetermined constitution or reaction products thereof, e.g. transplant tissue, natural bone, extracellular matrix characterised by the site of application in the body
- A61L27/3645—Connective tissue
- A61L27/365—Bones
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
- A61L27/36—Materials for grafts or prostheses or for coating grafts or prostheses containing ingredients of undetermined constitution or reaction products thereof, e.g. transplant tissue, natural bone, extracellular matrix
- A61L27/3683—Materials for grafts or prostheses or for coating grafts or prostheses containing ingredients of undetermined constitution or reaction products thereof, e.g. transplant tissue, natural bone, extracellular matrix subjected to a specific treatment prior to implantation, e.g. decellularising, demineralising, grinding, cellular disruption/non-collagenous protein removal, anti-calcification, crosslinking, supercritical fluid extraction, enzyme treatment
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L2430/00—Materials or treatment for tissue regeneration
- A61L2430/02—Materials or treatment for tissue regeneration for reconstruction of bones; weight-bearing implants
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L2430/00—Materials or treatment for tissue regeneration
- A61L2430/40—Preparation and treatment of biological tissue for implantation, e.g. decellularisation, cross-linking
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- General Health & Medical Sciences (AREA)
- Medicinal Chemistry (AREA)
- Epidemiology (AREA)
- Veterinary Medicine (AREA)
- Public Health (AREA)
- Animal Behavior & Ethology (AREA)
- Dermatology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Chemistry (AREA)
- Molecular Biology (AREA)
- Transplantation (AREA)
- Gastroenterology & Hepatology (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Zoology (AREA)
- Botany (AREA)
- Proteomics, Peptides & Aminoacids (AREA)
- Vascular Medicine (AREA)
- Orthopedic Medicine & Surgery (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Toxicology (AREA)
- Biochemistry (AREA)
- Biophysics (AREA)
- Genetics & Genomics (AREA)
- Immunology (AREA)
- Pharmacology & Pharmacy (AREA)
- Materials For Medical Uses (AREA)
Abstract
Abstract of the Disclosure A collagen-based, bone substitute material is produced from bone, particularly calf bone, in a multistep process in which the bone is water washed, treated with H202 solution, water washed, degreased with an organic solvent, the mineral content eliminated, the salts are removed by a water rinse, and the product is sterilized.
Description
`` 3L1~2~30 This invention relates to a collagen-based material useful as a bone substitute material with improved biological acceptability and stability.
BONE IMPLANTATION BACKGROUND
-Very often during surgery it is necessary to fill bone defects with a filler material. This is necessary particularly as a result of injuries due to accidents which lead to bone fractures involving loss of bone substance or bone penetration. However, there are many other uses for bone filler material as, for example, filling cavities following removal of bone tumors or withdrawal of bone cysts.
Moreover, a bone filler material is required in those cases where, in the scope of corrective measures, a surgeon is required to fill up a cavity present initially in the bone, or created by the surgeon himself.
Based on the present state of the art of surgery, the most appropriate bone-filler material is autologous spongiosa or an autological cortico-spongeous chip (Vnfall-heilkunde [Traumatology], 81, 565 - 567 [1978]). Such bone filler material originates with the recipient. The donor of the bone and the recipient axe thus the same.
The homologous transplanation of human bones from one person to another one likewise is customary. For this purpose, bone banks are set up in certain places which keep appropriate bone material available. Moreover, the transplanation of animal bones, which are first subjected to an appropriate method of preparation like storage ïn
BONE IMPLANTATION BACKGROUND
-Very often during surgery it is necessary to fill bone defects with a filler material. This is necessary particularly as a result of injuries due to accidents which lead to bone fractures involving loss of bone substance or bone penetration. However, there are many other uses for bone filler material as, for example, filling cavities following removal of bone tumors or withdrawal of bone cysts.
Moreover, a bone filler material is required in those cases where, in the scope of corrective measures, a surgeon is required to fill up a cavity present initially in the bone, or created by the surgeon himself.
Based on the present state of the art of surgery, the most appropriate bone-filler material is autologous spongiosa or an autological cortico-spongeous chip (Vnfall-heilkunde [Traumatology], 81, 565 - 567 [1978]). Such bone filler material originates with the recipient. The donor of the bone and the recipient axe thus the same.
The homologous transplanation of human bones from one person to another one likewise is customary. For this purpose, bone banks are set up in certain places which keep appropriate bone material available. Moreover, the transplanation of animal bones, which are first subjected to an appropriate method of preparation like storage ïn
2 -ethylmercuri-mercapto-benzoxaZol-5-carbons~ure-natrium -cialite solution or the method disclosed in the German patent 961,654, is known and customary.
~ ` ~
The best surgical results have been achieved up to now at the site of the bone implantation by using bone removed from the same patient who is provided with the bone filler material (autologous transplantation). However, there are two important disadvantages with autologous trans-plantation and they are:
1. The bone substitute material must be obtained by an additional surgical operation. The additional surgical operation, which increases the operating time, may be very detrimental to the patient and, in individual cases, even may be life-threatening. This danger will affect primarily the seriously injured, older patients or patients pre-afflicted with other general ailments which are separate from that requiring the surgical operation. Moreover, the additional surgery leads to increased loss of blood and additional pain for the patient. Also, each surgical operation entails a certain amount of complications which may lead to additional damage which cannot always be anticipated in each individual case.
2. The quantity of autological bone material available is limited. The available reservoirs are the pelvic combs on both sides, ribs, the tibia head and the parts of the radius distal from the body. Even complete utilization of these sources, which requires a plurality of surgical operations, may not furnish an adequate quantity of bone substitute material in every case. If the bone need is greater than that obtainable from the patient, the surgeon must either utilize less bone replacement material than desired or he must resort to use of less suitable human or animal bones.
~ ~ ~243~
In homologous bone transplantation from one human to another, the bone transplant frequently is not tolerated well by the recipient. Primarily responsible for this is the formation of antibodies against foreign protein. Moreover, appropriate donor bone material is hard to obtain. As a rule, it is necessary to resort to use of bones removed from bodies which have already deteriorated considerably.
In addition, the transmission of infections to the recipient by use of such bone cannot be ruled out.
The use of heterological transplantation material, like Kiel bone chip according to German patent 961,654, has demonstrated over the course of many years that this material is not well tolerated by some patients. Frequently, the bone fragments implanted by the surgeon are not converted into live bone tissue but remain in the tissue as dead material.
SUMMARY OF THE INVENTION
According to the invention, there is provided a collagen-based product, and process of making the product, which can be used as a bone substitute material and which can be made available in large quantities.
The material, upon implantation into the human or animal body, creates no antibodies, is of excellent tissue compatibility and after being implanted into the body is converted into bone tissue.
PRODUCTION OF THE PRODUCT OF THE INVENTION
Bones, and specifically bovine bone material, for example from the calf, preferably are used as the starting 11fl~2~
material in making the bone substitute according to the invention. However, other starting materials such as tendons, skins, human bones and similar material containing collagen, also may be used. The subsequently described method for the production oE the material according to the invention is based on the use of calf bones as starting material by way of an examp]e. The method of the invention represents a combination of steps which are carried out in the disclosed sequence, to obtain the bone substitute material with improved biological stability, according to the invention.
In a first step of the method, the bones are rinsed with water sufficiently long to remove blood pigment and other water-soluble proteins. This rinsing period usually takes 2 to 3 days During this rinsing, the washing water is renewed frequently. The rinsing also can be carried out by rinsing the bones in running water. No particular temperature is required, but the rinsing may be carried out appropriately at ambient temperatureO
In a second step of the method, removal af an additional protein content, not soluble in water, is effected.
It lS important that foreign proteins outside the collagen, like bone cells for example, be removed to prevent anti-reactions by the formation of antibodies, even those of an enzymatic kind. The removaI of the protein content in this step is accomplished by putting the bone material in a protein remover as, for example, in an H2O2 soluticn.
This H2O2 solution should have a concentration of more than 10%. The duration of the treatment normally amounts to 2 to 3 days. Here again, the H2O2 solution should be renewed repeatedly to assure complete removal of the protein content.
~ 42430 Step thxee again comprises a rinsing step. The material from step two is rinsed with cold water to rinse out and remove the dissolved soft parts. Rinsing under running water is advantageously used in this step.
In step four of the method, the material thusly obtained from step three is degreased. The degreasing is done with an organic solvent or mixture thereof. Appropriate solvents are, for example, acetone or ether or specifically a combinatin of both solvents. The degreasing may be accom-plished by contacting the bone material with the solvent in any equipment appropriate therefor. A Soxhlet apparatus is particularly appropriate for this degreasing.
In step five of the method, the bone material from ste~ four is treated with a complexing agent or an ion exchanger. The purpose of this step is to eliminate the mineral content of the bone. The salts of ethylenediamine tetraacetic acid are appropriate complex formers which can be used.
A suitable solution of a complexin~ agent can be produced according to a method disclosed in Romeis "Lehr-buch der Mikroskopischen Technik" (Textbook of Microscopic Technique). Thus, 250 grams of disodium ethylenediamine tetraacetic acid are treated with 200 cc of distilled water and heated. With continuous agitation, 50 cc of a 40% sodium hydroxide solution are added and then the mixture volume is increased to 800 cc with distilled water. By dropwise addition of 40% sodium hydroxide, the pH is adjusted to 7.4 and then the volume is adjusted with distilled water to a total volume of 1000 cc.
4;~3~
The bone material is immersed into a complexing solution, such as the one just described, and left therein for quite some time, for example up to several weeks, until a rubber-like elastic product is obtained.
The rubber-like elastic product thusly obtained is washed in a sixth step of the method to remove the salt residues present. The washing is done by rinsing ~nder running water for an adequate time, like 2 to 3 days for example.
In step seven of -the method, the material thusly obtained is then subjected, if applicable, to freeze drying using conventional procedures.
In step eight of the method, the material obtained is subjected to sterilization, particularly by use of radia-tion sterilization. A radiation sterilization can be effected with the usual dose of 2.5 megarads.
In the above disclosed combination method, steps 1 to 3 and step 4 as such are known. According to German patent 961,954 a drying step is inserted after the operating step 3 and it is carried out at not more than 40C (104F) over a period of 12 to 24 hours. This drying step must not be applied in the present method because, if it is, the product according to the invention will not be obtained.
Thus, it is essential, after the step 3 rinsing to go to step 4, that is degreasing with an organic solvent, without first drying the product.
Step 5 of the method is known as such, for example, from the textbook by Romeis "Textbook of Microscopic Technique".
However, the combinatin of method steps 1 to 4 of the present invention, with method step 5 of the invention, was not previously known.
2~1~3~
~`
Method steps 6 to 8 relate to method steps previous-ly known per se. However, these steps too were not previous-ly used in combination with the method steps 1 to 5 of the present invention.
USE O~ THE PRODUCT AS A BONE SU~STITUTE MATERIAL
The product produced as described above is a useful bone substitute material of purified collagen, and especially purified calf collagen. The process preserves its molecular structure, to a large extent by carefully avoiding all detri-mental factors, like acid, during the decalcification process.
The product can be used as a bone implant by placing it-in a bone defect in the dry state as obtalned by the described process, or as a paste formed by mixing it with saline solution.
The bone suhstitute material thus obtained, upon implantation into the body, has surprisingly good qualities.
For example, the resorption time is substantially higher than in other previously known and used materials. Moreover, fine-tissue examinations at various points in time following implantation into guinea pigs demonstrated an excellent compatibility without rejection reactions by the body.
As soon as two weeks after implantation, the start of conver-sion of the material into bone tissues was observed. Fine tissue examinations showed deposits of mineral substance, connective tissue cells, sprouting blood vessels and bone-forming cells.
ENHANCED RESULTS BY CALCITONIN ADDITION
The outstanding properties of the material obtained according to the invention can be improved substantially ~ L4Z~3t~
.
as a bone substitute material by blending this material with a small quantity of the hormone calcitonin, also called thyrocalcitonin. For example, calcitonin solutions commer-cially available are appropriately used. The subs-tantially improved results obtained by such a combination apparently are due to a s~nergistic effect between the basic bone substi-tute material and the hormone calcitonin. The time required for new bone formation is reduced considerably when the bone substitute material is treated with calcitonin.
The followinq example is presented to further illustrate the invention.
Example One kilogram of calf bones (spongiosa pieces) are washed carefully and thus freed of coarse blood residues.
This quantity of bones is then placed in an appropriate vessel, having inlet and outlet connections, and rinsed for 72 hours with running tap water. The bone is then im-mersed for 72 hours in an H2O2 solution (15%). The solution is changed 3 to 4 times. The bones are then rinsed with running tap water for 24 hours. Subsequently, the bones are degreased in a Soxhlet apparatus using 60% acetone and 40~ diethyl ether over a period of about 12 hours.
1250 grams of disodium ethylenediamine tetraacetic acid is added to 1000 cc of distilled water and the mixture is then heated. With continuous mixing, 200 cc of a 40 sodium hydroxide solution is added and then the mixture is brought to a 4000 cc volume by addition of distilIed water. The mixture is adjusted to a pH of 7.4 by the dropwise addition of a 40% sodium hydroxide solution. Then distilled water is added to attain a 5000 cc volume.
~ L42~30 The bones treated as described above are immersed in the solution so produced until several samples taken out prove to be free from minerals. About 3 to 4 weeks at room temperature will be required, depending on the size of the individual pieces.
Another degreasing of the bone material is carried out with 60% acetone and 40~ diethyl ether in a Soxhlet apparatus over about 12 hours. Subsequently, the bone mate-rial is freeze-dried. This is followed, after appropriate foil wrapping, by radiation with 2.5 Mrad. for sterilization.
The following experiments used the bone substitute material produced according to this example, with the de-scribed results.
The bone substitute material according to the invention was tested in rats and rabbits for its properties.
The collagen matrix was implanted into the animals subcutane-ously and into the dorsal muscular system. The implants were removed from various groups after 1, 2, 4, 8, and 12 weeks and examined histologically.
The growth of fine blood vessels and cells as soon as one week after implantation was observed. Chondro-blasts, fibroblasts and osteoblasts (cartillage, connective tissue and bone-forming cells) was observed after 2 weeks.
As time passed there was progressive structuring and restruc-turing until regular bone structures formed.
The foregoing detailed description has been given for clearness of understanding only, ànd no unnecessary limitations should be understood therefrom, as modifications will be obvious to those skilled in the art.
~ ` ~
The best surgical results have been achieved up to now at the site of the bone implantation by using bone removed from the same patient who is provided with the bone filler material (autologous transplantation). However, there are two important disadvantages with autologous trans-plantation and they are:
1. The bone substitute material must be obtained by an additional surgical operation. The additional surgical operation, which increases the operating time, may be very detrimental to the patient and, in individual cases, even may be life-threatening. This danger will affect primarily the seriously injured, older patients or patients pre-afflicted with other general ailments which are separate from that requiring the surgical operation. Moreover, the additional surgery leads to increased loss of blood and additional pain for the patient. Also, each surgical operation entails a certain amount of complications which may lead to additional damage which cannot always be anticipated in each individual case.
2. The quantity of autological bone material available is limited. The available reservoirs are the pelvic combs on both sides, ribs, the tibia head and the parts of the radius distal from the body. Even complete utilization of these sources, which requires a plurality of surgical operations, may not furnish an adequate quantity of bone substitute material in every case. If the bone need is greater than that obtainable from the patient, the surgeon must either utilize less bone replacement material than desired or he must resort to use of less suitable human or animal bones.
~ ~ ~243~
In homologous bone transplantation from one human to another, the bone transplant frequently is not tolerated well by the recipient. Primarily responsible for this is the formation of antibodies against foreign protein. Moreover, appropriate donor bone material is hard to obtain. As a rule, it is necessary to resort to use of bones removed from bodies which have already deteriorated considerably.
In addition, the transmission of infections to the recipient by use of such bone cannot be ruled out.
The use of heterological transplantation material, like Kiel bone chip according to German patent 961,654, has demonstrated over the course of many years that this material is not well tolerated by some patients. Frequently, the bone fragments implanted by the surgeon are not converted into live bone tissue but remain in the tissue as dead material.
SUMMARY OF THE INVENTION
According to the invention, there is provided a collagen-based product, and process of making the product, which can be used as a bone substitute material and which can be made available in large quantities.
The material, upon implantation into the human or animal body, creates no antibodies, is of excellent tissue compatibility and after being implanted into the body is converted into bone tissue.
PRODUCTION OF THE PRODUCT OF THE INVENTION
Bones, and specifically bovine bone material, for example from the calf, preferably are used as the starting 11fl~2~
material in making the bone substitute according to the invention. However, other starting materials such as tendons, skins, human bones and similar material containing collagen, also may be used. The subsequently described method for the production oE the material according to the invention is based on the use of calf bones as starting material by way of an examp]e. The method of the invention represents a combination of steps which are carried out in the disclosed sequence, to obtain the bone substitute material with improved biological stability, according to the invention.
In a first step of the method, the bones are rinsed with water sufficiently long to remove blood pigment and other water-soluble proteins. This rinsing period usually takes 2 to 3 days During this rinsing, the washing water is renewed frequently. The rinsing also can be carried out by rinsing the bones in running water. No particular temperature is required, but the rinsing may be carried out appropriately at ambient temperatureO
In a second step of the method, removal af an additional protein content, not soluble in water, is effected.
It lS important that foreign proteins outside the collagen, like bone cells for example, be removed to prevent anti-reactions by the formation of antibodies, even those of an enzymatic kind. The removaI of the protein content in this step is accomplished by putting the bone material in a protein remover as, for example, in an H2O2 soluticn.
This H2O2 solution should have a concentration of more than 10%. The duration of the treatment normally amounts to 2 to 3 days. Here again, the H2O2 solution should be renewed repeatedly to assure complete removal of the protein content.
~ 42430 Step thxee again comprises a rinsing step. The material from step two is rinsed with cold water to rinse out and remove the dissolved soft parts. Rinsing under running water is advantageously used in this step.
In step four of the method, the material thusly obtained from step three is degreased. The degreasing is done with an organic solvent or mixture thereof. Appropriate solvents are, for example, acetone or ether or specifically a combinatin of both solvents. The degreasing may be accom-plished by contacting the bone material with the solvent in any equipment appropriate therefor. A Soxhlet apparatus is particularly appropriate for this degreasing.
In step five of the method, the bone material from ste~ four is treated with a complexing agent or an ion exchanger. The purpose of this step is to eliminate the mineral content of the bone. The salts of ethylenediamine tetraacetic acid are appropriate complex formers which can be used.
A suitable solution of a complexin~ agent can be produced according to a method disclosed in Romeis "Lehr-buch der Mikroskopischen Technik" (Textbook of Microscopic Technique). Thus, 250 grams of disodium ethylenediamine tetraacetic acid are treated with 200 cc of distilled water and heated. With continuous agitation, 50 cc of a 40% sodium hydroxide solution are added and then the mixture volume is increased to 800 cc with distilled water. By dropwise addition of 40% sodium hydroxide, the pH is adjusted to 7.4 and then the volume is adjusted with distilled water to a total volume of 1000 cc.
4;~3~
The bone material is immersed into a complexing solution, such as the one just described, and left therein for quite some time, for example up to several weeks, until a rubber-like elastic product is obtained.
The rubber-like elastic product thusly obtained is washed in a sixth step of the method to remove the salt residues present. The washing is done by rinsing ~nder running water for an adequate time, like 2 to 3 days for example.
In step seven of -the method, the material thusly obtained is then subjected, if applicable, to freeze drying using conventional procedures.
In step eight of the method, the material obtained is subjected to sterilization, particularly by use of radia-tion sterilization. A radiation sterilization can be effected with the usual dose of 2.5 megarads.
In the above disclosed combination method, steps 1 to 3 and step 4 as such are known. According to German patent 961,954 a drying step is inserted after the operating step 3 and it is carried out at not more than 40C (104F) over a period of 12 to 24 hours. This drying step must not be applied in the present method because, if it is, the product according to the invention will not be obtained.
Thus, it is essential, after the step 3 rinsing to go to step 4, that is degreasing with an organic solvent, without first drying the product.
Step 5 of the method is known as such, for example, from the textbook by Romeis "Textbook of Microscopic Technique".
However, the combinatin of method steps 1 to 4 of the present invention, with method step 5 of the invention, was not previously known.
2~1~3~
~`
Method steps 6 to 8 relate to method steps previous-ly known per se. However, these steps too were not previous-ly used in combination with the method steps 1 to 5 of the present invention.
USE O~ THE PRODUCT AS A BONE SU~STITUTE MATERIAL
The product produced as described above is a useful bone substitute material of purified collagen, and especially purified calf collagen. The process preserves its molecular structure, to a large extent by carefully avoiding all detri-mental factors, like acid, during the decalcification process.
The product can be used as a bone implant by placing it-in a bone defect in the dry state as obtalned by the described process, or as a paste formed by mixing it with saline solution.
The bone suhstitute material thus obtained, upon implantation into the body, has surprisingly good qualities.
For example, the resorption time is substantially higher than in other previously known and used materials. Moreover, fine-tissue examinations at various points in time following implantation into guinea pigs demonstrated an excellent compatibility without rejection reactions by the body.
As soon as two weeks after implantation, the start of conver-sion of the material into bone tissues was observed. Fine tissue examinations showed deposits of mineral substance, connective tissue cells, sprouting blood vessels and bone-forming cells.
ENHANCED RESULTS BY CALCITONIN ADDITION
The outstanding properties of the material obtained according to the invention can be improved substantially ~ L4Z~3t~
.
as a bone substitute material by blending this material with a small quantity of the hormone calcitonin, also called thyrocalcitonin. For example, calcitonin solutions commer-cially available are appropriately used. The subs-tantially improved results obtained by such a combination apparently are due to a s~nergistic effect between the basic bone substi-tute material and the hormone calcitonin. The time required for new bone formation is reduced considerably when the bone substitute material is treated with calcitonin.
The followinq example is presented to further illustrate the invention.
Example One kilogram of calf bones (spongiosa pieces) are washed carefully and thus freed of coarse blood residues.
This quantity of bones is then placed in an appropriate vessel, having inlet and outlet connections, and rinsed for 72 hours with running tap water. The bone is then im-mersed for 72 hours in an H2O2 solution (15%). The solution is changed 3 to 4 times. The bones are then rinsed with running tap water for 24 hours. Subsequently, the bones are degreased in a Soxhlet apparatus using 60% acetone and 40~ diethyl ether over a period of about 12 hours.
1250 grams of disodium ethylenediamine tetraacetic acid is added to 1000 cc of distilled water and the mixture is then heated. With continuous mixing, 200 cc of a 40 sodium hydroxide solution is added and then the mixture is brought to a 4000 cc volume by addition of distilIed water. The mixture is adjusted to a pH of 7.4 by the dropwise addition of a 40% sodium hydroxide solution. Then distilled water is added to attain a 5000 cc volume.
~ L42~30 The bones treated as described above are immersed in the solution so produced until several samples taken out prove to be free from minerals. About 3 to 4 weeks at room temperature will be required, depending on the size of the individual pieces.
Another degreasing of the bone material is carried out with 60% acetone and 40~ diethyl ether in a Soxhlet apparatus over about 12 hours. Subsequently, the bone mate-rial is freeze-dried. This is followed, after appropriate foil wrapping, by radiation with 2.5 Mrad. for sterilization.
The following experiments used the bone substitute material produced according to this example, with the de-scribed results.
The bone substitute material according to the invention was tested in rats and rabbits for its properties.
The collagen matrix was implanted into the animals subcutane-ously and into the dorsal muscular system. The implants were removed from various groups after 1, 2, 4, 8, and 12 weeks and examined histologically.
The growth of fine blood vessels and cells as soon as one week after implantation was observed. Chondro-blasts, fibroblasts and osteoblasts (cartillage, connective tissue and bone-forming cells) was observed after 2 weeks.
As time passed there was progressive structuring and restruc-turing until regular bone structures formed.
The foregoing detailed description has been given for clearness of understanding only, ànd no unnecessary limitations should be understood therefrom, as modifications will be obvious to those skilled in the art.
Claims (9)
OR PRIVILEGE IS CLAIMED ARE DEFINES AS FOLLOWS:
1. A product useful as a bone substitute material with improved acceptability and stability consisting of natural collagen, which is preserved to a large extent as to its molecular structure, produced by the following method:
a) removing the blood pigment and other water-soluble proteins from natural collagen-containing material by treatment with water;
b) removing proteins from the material by treatment with H202 solution;
c) rinsing the material in cold water;
d) degreasing the material with an organic solvent;
e) eliminating the mineral content of the collagen material;
f) removing the residual salts from the material by rinsing with water; and g) sterilizing the product.
a) removing the blood pigment and other water-soluble proteins from natural collagen-containing material by treatment with water;
b) removing proteins from the material by treatment with H202 solution;
c) rinsing the material in cold water;
d) degreasing the material with an organic solvent;
e) eliminating the mineral content of the collagen material;
f) removing the residual salts from the material by rinsing with water; and g) sterilizing the product.
2. A product according to claim l, characterized by using a bone material as starting material.
3. A product according to claim 2 in which the bone material is calf bones.
4. A product according to claims 1 and 2, contain-ing the hormone calcitonine.
5. A process of producing a product useful as a bone substitute material, which comprises:
a) removing the blood pigment and other water-soluble proteins from animal bones by rinsing them with water;
b) removing proteins from the bones by treating them with a H2O2 solution;
c) rinsing the bones in cold water;
d) degreasing the bones with an organic solvent;
e) eliminating the mineral content from the bone material;
f) removing the residual salts from the bone material by rinsing with water; and g) sterilizing the bone material.
a) removing the blood pigment and other water-soluble proteins from animal bones by rinsing them with water;
b) removing proteins from the bones by treating them with a H2O2 solution;
c) rinsing the bones in cold water;
d) degreasing the bones with an organic solvent;
e) eliminating the mineral content from the bone material;
f) removing the residual salts from the bone material by rinsing with water; and g) sterilizing the bone material.
6. A process according to claim 5 in which the bone material is freeze-dried between steps f and g.
7. A process according to claim 5 in which the hormone calcitonin is added to the product.
8. A process according to claim 5 in which the mineral content is removed in step e by use of a complexing agent or an ion exchanger.
9. A process according to claim 5 in which the bones are calf bones.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DEP2854490.3 | 1978-12-16 | ||
DE2854490A DE2854490C2 (en) | 1978-12-16 | 1978-12-16 | Bone substitute material with improved biological stability based on collagen |
Publications (1)
Publication Number | Publication Date |
---|---|
CA1142430A true CA1142430A (en) | 1983-03-08 |
Family
ID=6057451
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA000341820A Expired CA1142430A (en) | 1978-12-16 | 1979-12-13 | Bone substitute material and its use |
Country Status (7)
Country | Link |
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EP (1) | EP0012959B1 (en) |
JP (1) | JPS5584161A (en) |
AT (1) | ATE944T1 (en) |
CA (1) | CA1142430A (en) |
DE (2) | DE2854490C2 (en) |
DK (1) | DK154892C (en) |
ES (1) | ES486893A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5531791A (en) * | 1993-07-23 | 1996-07-02 | Bioscience Consultants | Composition for repair of defects in osseous tissues, method of making, and prosthesis |
Families Citing this family (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4430760A (en) * | 1981-12-18 | 1984-02-14 | Collagen Corporation | Nonstress-bearing implantable bone prosthesis |
DE3124981A1 (en) * | 1981-06-25 | 1983-01-13 | Dr. Ruhland Nachfolger GmbH, 8425 Neustadt | ACTIVE INGREDIENT COLLAGEN INSERT FOR INSERTION INTO BONES OR SOFT PARTS AND METHOD FOR THEIR PRODUCTION |
EP0141004B1 (en) * | 1983-10-20 | 1988-01-07 | Oscobal Ag | Bone substitute material based on natural bone |
US4789663A (en) * | 1984-07-06 | 1988-12-06 | Collagen Corporation | Methods of bone repair using collagen |
JPS6162459A (en) * | 1984-07-06 | 1986-03-31 | コラ−ゲン コ−ポレイシヨン | Repairing of bone using collagen |
US5522894A (en) * | 1984-12-14 | 1996-06-04 | Draenert; Klaus | Bone replacement material made of absorbable beads |
US4627853A (en) * | 1985-05-29 | 1986-12-09 | American Hospital Supply Corporation | Method of producing prostheses for replacement of articular cartilage and prostheses so produced |
US4678470A (en) * | 1985-05-29 | 1987-07-07 | American Hospital Supply Corporation | Bone-grafting material |
US5053049A (en) * | 1985-05-29 | 1991-10-01 | Baxter International | Flexible prostheses of predetermined shapes and process for making same |
AT398373B (en) * | 1987-12-17 | 1994-11-25 | Immuno Ag | BIOLOGICAL RESORBABLE IMPLANTATION MATERIAL AND METHOD FOR PRODUCING THE SAME |
US4975526A (en) * | 1989-02-23 | 1990-12-04 | Creative Biomolecules, Inc. | Bone collagen matrix for zenogenic implants |
DE3835237C1 (en) * | 1988-10-15 | 1989-12-28 | B. Braun Melsungen Ag, 3508 Melsungen, De | |
EP0424159A3 (en) * | 1989-10-19 | 1991-11-06 | Osteotech, Inc., | Aseptic processing of allograft bone and tissue |
DE4425776C2 (en) * | 1994-07-13 | 2002-08-29 | Britta Hofmann | Process for the preparation of an improved collagen graft with a loosened structure |
IT1268641B1 (en) * | 1994-10-24 | 1997-03-06 | Giuseppe Oliva | INACTIVATION AND ELIMINATION OF ORGANIC MATRIX FROM ANIMAL BONE FOR HETEROTOPICAL XENOTOPLANTS. |
FR2752382B1 (en) * | 1996-08-16 | 1998-10-09 | Assist Publ Hopitaux De Paris | PROCESS FOR THE TREATMENT OF HUMAN OR ANIMAL PRODUCTS FOR THERAPEUTIC USE |
US5972368A (en) * | 1997-06-11 | 1999-10-26 | Sdgi Holdings, Inc. | Bone graft composites and spacers |
DE10157182A1 (en) * | 2001-11-22 | 2003-06-05 | Matricel Gmbh | Process for the treatment of materials of biological origin and elastin product |
AT413075B (en) * | 2003-02-25 | 2005-11-15 | Austria Wirtschaftsserv Gmbh | METHOD FOR PRODUCING A BONE IMPLANT MATERIAL AND DEVICE FOR CARRYING OUT THIS METHOD |
GB2431408A (en) * | 2005-10-19 | 2007-04-25 | Osta Technologies Cc | Bone material and a process for the preparation of bone material |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE961654C (en) * | 1954-06-16 | 1957-04-11 | Armin Bauermeister | Process for the preparation of bones suitable for transplantation |
GB1068587A (en) * | 1963-12-06 | 1967-05-10 | Biorex Laboratories Ltd | Dental fillers and bone cements comprising collagen |
SU498005A1 (en) * | 1971-08-13 | 1976-01-05 | Центральный научно-исследовательский институт стоматологии | Stimulating anti-inflammatory agent for treatment in dentistry |
-
1978
- 1978-12-16 DE DE2854490A patent/DE2854490C2/en not_active Expired
-
1979
- 1979-12-13 DK DK530279A patent/DK154892C/en active
- 1979-12-13 CA CA000341820A patent/CA1142430A/en not_active Expired
- 1979-12-14 AT AT79105190T patent/ATE944T1/en not_active IP Right Cessation
- 1979-12-14 DE DE7979105190T patent/DE2962750D1/en not_active Expired
- 1979-12-14 EP EP79105190A patent/EP0012959B1/en not_active Expired
- 1979-12-14 ES ES486893A patent/ES486893A1/en not_active Expired
- 1979-12-15 JP JP16344279A patent/JPS5584161A/en active Granted
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5531791A (en) * | 1993-07-23 | 1996-07-02 | Bioscience Consultants | Composition for repair of defects in osseous tissues, method of making, and prosthesis |
Also Published As
Publication number | Publication date |
---|---|
JPS619857B2 (en) | 1986-03-26 |
DE2962750D1 (en) | 1982-06-24 |
JPS5584161A (en) | 1980-06-25 |
EP0012959A1 (en) | 1980-07-09 |
DE2854490B1 (en) | 1980-06-12 |
ES486893A1 (en) | 1980-07-01 |
DK530279A (en) | 1980-06-17 |
ATE944T1 (en) | 1982-05-15 |
DK154892B (en) | 1989-01-02 |
EP0012959B1 (en) | 1982-05-05 |
DE2854490C2 (en) | 1981-04-09 |
DK154892C (en) | 1989-06-05 |
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