WO1989005161A1 - Couche de glissement pour endoprotheses d'articulations et son procede de production - Google Patents

Couche de glissement pour endoprotheses d'articulations et son procede de production Download PDF

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Publication number
WO1989005161A1
WO1989005161A1 PCT/EP1987/000768 EP8700768W WO8905161A1 WO 1989005161 A1 WO1989005161 A1 WO 1989005161A1 EP 8700768 W EP8700768 W EP 8700768W WO 8905161 A1 WO8905161 A1 WO 8905161A1
Authority
WO
WIPO (PCT)
Prior art keywords
layer
sliding
tio
sliding layer
joint
Prior art date
Application number
PCT/EP1987/000768
Other languages
German (de)
English (en)
Inventor
Heiko Gruner
Original Assignee
Plasmainvent Ag
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Plasmainvent Ag filed Critical Plasmainvent Ag
Priority to EP88900222A priority Critical patent/EP0348389A1/fr
Priority to PCT/EP1987/000768 priority patent/WO1989005161A1/fr
Publication of WO1989005161A1 publication Critical patent/WO1989005161A1/fr

Links

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61FFILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/02Prostheses implantable into the body
    • A61F2/30Joints
    • A61F2/38Joints for elbows or knees
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61LMETHODS 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
    • A61L27/00Materials for grafts or prostheses or for coating grafts or prostheses
    • A61L27/28Materials for coating prostheses
    • A61L27/30Inorganic materials
    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23CCOATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C4/00Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • C23C4/02Pretreatment of the material to be coated, e.g. for coating on selected surface areas
    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23CCOATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C4/00Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • C23C4/04Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
    • C23C4/10Oxides, borides, carbides, nitrides or silicides; Mixtures thereof
    • C23C4/11Oxides
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61LMETHODS 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
    • A61L2430/00Materials or treatment for tissue regeneration
    • A61L2430/24Materials or treatment for tissue regeneration for joint reconstruction

Definitions

  • the invention relates to a sliding layer made of TiO 2 applied directly to the sliding surface of a joint endoprosthesis or via an intermediate layer, and to a method for the production thereof.
  • the first group includes e.g. Bone cement with which an endoprosthesis is anchored in the bone tissue immediately during the operation.
  • the metallic endoprostheses themselves can also be assigned to the first group.
  • Body compatibility in connection with the required mechanical stability limit the metals suitable for endoprostheses to essentially stainless steel, CoCr alloys, titanium and titanium alloys.
  • joint endoprostheses e.g. artificial knee or hip joints
  • good sliding properties in the joint area are required, while maintaining body tolerance.
  • metals and suitable for endoprostheses are
  • Metal alloys not satisfactory sliding properties.
  • the titanium and titanium alloys which are preferred for reasons of weight and because of their good mechanical properties, are not sufficiently resistant to abrasion under the specific joint load.
  • the corrosive conditions in the human body intensify this effect, whereby metallic abrasion and corrosion products arise in the artificial joint capsule.
  • the toughness of the titanium alloys, their tendency to weld with the machining tool and their poor thermal conductivity also make it more difficult to produce suitable smooth sliding surfaces.
  • the combination of ceramic and plastic has proven to be an almost ideal joint design.
  • the state of the art is, for example, to provide a hip joint prosthesis made of Ti alloy with a joint head made of Al 2 O 3 ceramic and to combine this with a joint socket made of polyethylene as a joint partner, which in turn is inserted into a metallic joint socket.
  • knee joints for example, cannot be realized in this embodiment.
  • the metallic femur slides in one in an artificial knee joint plastic tibia attached to the tibia.
  • the much heavier CoCr alloy is preferred for the production of the metallic femur, which has relatively better, but poorer sliding properties compared to ceramic.
  • artificial shoulder or hip joints also require metallic joint balls in certain cases.
  • an Al 2 O 3 spray layer always consists of a mixture of ⁇ and Phase phases. Since the ⁇ phase dissolves in the body, the life of the injected is Al 2 O 3 - sliding surface limited. It is not possible to convert the ⁇ phase into the ⁇ phase by means of an annealing process after spraying, since the mechanical properties of the metallic carriers change unfavorably at the required temperatures.
  • TiO 2 has also already been produced on joint balls, firstly galvanically (Biomaterials 1981, pages 221 to 224) and secondly by anodic oxidation. Both types of layers are not dense enough or tend to flake off.
  • the invention is therefore based on the object of providing a sliding layer of the type described at the outset, which adheres very well to the metallic materials for endoprostheses, is absolutely tolerable to the body and corrosion-resistant, in particular does not dissolve in the body and has internal structural stability in order to achieve the necessary mechanical processing allow for the production of smooth sliding surfaces, which the
  • Ceramic should have sliding properties combined with its abrasion resistance.
  • the sliding layer sprayed onto the sliding area of the metallic joint endoprosthesis is a bioinert TiO 2 layer with a pore-free, particularly compact and pronounced lamellar structure, which is, however, only visible in the metallographic micrograph by etching.
  • a biotolerant Ti layer as an intermediate layer and is advantageous on the joint endoprosthesis Retainer and then immediately sprayed onto the bioinert TiO 2 layer.
  • a method according to the invention for producing such sliding layers is characterized in that, after a method of thermal spraying which enables very high particle speeds, TiO 2 powder particles are melted and used as
  • Liquid droplets with high kinetic energy are deposited on the surface of the joint endoprosthesis. They burst and form flat spray cakes, which build up the compact and pore-free spray layer in a lamella-like manner.
  • Vacuum plasma spraying (VPS) manufactured, taking advantage of the known advantages of this
  • Coating technology e.g. are described in DE-A-34 22 718. This coating technique is also preferred for reasons of hygiene.
  • This process allows the TiO 2 ceramic to be injected so that it is structurally stable and at the same time so thick that on the one hand the required surface smoothness is achieved by mechanical finishing, on the other hand enough layer as a grinding reserve is present, for example to minimize joint roundness values.
  • the layer porosity is well below 1%, which is very important for the surface quality that can be achieved.
  • the surface of the joint endoprosthesis to be coated is expediently degreased in the area of the sliding surface by sandblasting with pure cC-Al-O-. roughened, freed of oxide skin immediately before coating with a transferred arc and at the same time slightly warmed and degassed.
  • Ti wettable powder grain size must be limited to 40 ⁇ m so that a relatively smooth boundary with the subsequent TiO 2 layer is created.
  • the TiO 2 sprayed layer has a layer thickness of at least 50 ⁇ m, is preferably 0.1 mm thick and only exceeds 0.2 mm in special cases.
  • the TiO 2 layer is produced using wettable powder with a grain size of 5 to 25 ⁇ m.
  • the coating is preferably carried out at a chamber pressure of 100 mbar for the Ti layer and the TiO 2 layer as the actual sliding layer.
  • the Ti layer of the sliding layer according to the invention is sprayed on with a non-reducing plasma flame and the TiO 2 layer is sprayed on with a reducing plasma flame.
  • the Ti layer as an adhesive layer can be dispensed with, in particular if the TiO 2 layer does not exceed 100 ⁇ m.
  • Fig. 1 shows a section parallel to the femur axis in a schematic representation of a femoral prosthesis for an artificial knee joint.
  • Fig. 2 shows an enlarged view of the
  • FIG. 1 shows a joint endoprosthesis 1.
  • a femoral prosthesis was deliberately chosen, the uncoated, original sliding surface 2 of which was roughened by sandblasting with ⁇ -Al 2 O- 3 particles to an average roughness of approximately 30 ⁇ m, with the aid of a transferred electric arc immediately before the natural coating
  • the surface 2 to be coated is cleaned with the sliding layer at a chamber pressure of 100 mbar using a non-reducing plasma flame, preferably with an Ar / He gas mixture in the absence of H 2 .
  • a Ti layer 31 is first sprayed on tightly and firmly, the flame energy thus is set that all powder particles are melted.
  • the layer thickness of this first layer of the sliding layer 3 is less than 50 ⁇ -m, its surface 33 has an average roughness due to the selected Ti powder grain size less than 20 ⁇ m.
  • the chamber pressure corresponds to the pressure for surface cleaning.
  • the plasma gas composition and the flame energy are adjusted so that the injected powder particles melt completely and form a thick layer composite.
  • the TiO 2 layer is sprayed on as the actual sliding layer without interruption, with the chamber vacuum remaining constant, but with adaptation of the flame energy by regulating the arc current and the flame enthalpy by changing the Ar / He mixing ratio and adding H 2 .
  • Their structure is extra low in pores and compact. Due to the kinetic impact energy of the molten TiO 2 particles, the desired lamellar layer structure 35 is formed, which, however, is not visible in the pure micrograph. Due to the particle speed in the ArHeH 2 -
  • Vacuum plasma flame the residence time of the molten TiO 2 droplets above the process temperature critical for a loss of O 2 is much shorter than in comparable processes of thermal spraying.
  • the TiO 2 layer 32 produced according to the invention is harder and more stable and does not yet show the otherwise typical lamellar structure in the pure micrograph, which is caused by O 2 losses.
  • the layer thickness of the TiO 2 layer 32 is preferably 100 ⁇ m and exceeds 200 ⁇ m only in special cases.
  • the Ti layer 31 as an adhesive layer can be dispensed with.
  • the prerequisite for this is the mechanical preparation of the joint surface practically to the final dimension.
  • the sliding layer only has to be sprayed on so thick that only the TiO 2 layer 32 is always processed during the production of the surface quality, ie the Ti layer 31 or the carrier material is not worked out. In almost all cases, 100 ⁇ m TiO 2 thickness is sufficient for this.
  • TiO 2 powder with a grain size of 5 to 25 ⁇ m is preferably used for the TiO 2 layer 32.
  • the sliding layer surface 34 already has an average roughness of less than 10 ⁇ m, which means that the mechanical Postprocessing reduced.
  • the structural stability is improved by the finer spray cake 35, which favors the mechanical finishing.
  • Fine granularity of the spray powder in connection with the high flame temperature and particle speed extend the flight distance within which the injected particles have melted. Therefore, several joint endoprostheses are advantageously moved in the spray jet with special substrate holders so that their sliding surfaces are coated simultaneously and immediately one after the other.
  • the adhesive force of the sliding layer according to the invention made of TiO 2 , its spray layer density and internal structural stability and the surface quality thereby achieved in mechanical post-processing recommend its usability as a sliding surface in technical applications, for example for protecting a highly stressed propeller shaft.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Orthopedic Medicine & Surgery (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Transplantation (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Physics & Mathematics (AREA)
  • Metallurgy (AREA)
  • Plasma & Fusion (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Medicinal Chemistry (AREA)
  • Dermatology (AREA)
  • Epidemiology (AREA)
  • Inorganic Chemistry (AREA)
  • Physical Education & Sports Medicine (AREA)
  • Cardiology (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Vascular Medicine (AREA)
  • Coating By Spraying Or Casting (AREA)

Abstract

Afin d'assurer une bonne adhérence, une compatibilité organique absolue et la résistance à la corrosion d'une couche de glissement (31, 32) appliquée sur la surface de glissement (2) d'une endoprothèse (1) d'une articulation, on injecte sur la zone de glissement de l'endoprothèse métallique (1) d'une articulation premièrement une couche en Ti bicompatible (31), suivie immédiatement d'une couche (32) en TiO2 bio-inerte ayant une structure lamellaire marquée exempte de pores et particulièrement compacte. Dans des cas spéciaux, la couche en Ti (31) n'est pas nécessaire comme couche d'adhérence. La couche de glissement (31, 32) est produite selon un procédé d'injection thermique, de préférence par projection de plasma à vide.
PCT/EP1987/000768 1987-12-09 1987-12-09 Couche de glissement pour endoprotheses d'articulations et son procede de production WO1989005161A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP88900222A EP0348389A1 (fr) 1987-12-09 1987-12-09 Couche de glissement pour endoprotheses d'articulations et son procede de production
PCT/EP1987/000768 WO1989005161A1 (fr) 1987-12-09 1987-12-09 Couche de glissement pour endoprotheses d'articulations et son procede de production

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP1987/000768 WO1989005161A1 (fr) 1987-12-09 1987-12-09 Couche de glissement pour endoprotheses d'articulations et son procede de production

Publications (1)

Publication Number Publication Date
WO1989005161A1 true WO1989005161A1 (fr) 1989-06-15

Family

ID=8165222

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1987/000768 WO1989005161A1 (fr) 1987-12-09 1987-12-09 Couche de glissement pour endoprotheses d'articulations et son procede de production

Country Status (2)

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EP (1) EP0348389A1 (fr)
WO (1) WO1989005161A1 (fr)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1991003266A1 (fr) * 1989-08-31 1991-03-21 Böhler Ag Prothese
DE4005692A1 (de) * 1990-02-23 1991-08-29 Omt Oberflaechen Materialtech Verfahren zur herstellung von physiologisch vertraeglichen oxidschichten auf skelettimplantaten
EP0613667A1 (fr) * 1993-03-05 1994-09-07 SMITH & NEPHEW RICHARDS, INC. Implant fémoral de genou en matière plastique
US5976190A (en) * 1996-11-06 1999-11-02 Otto Bock Orthopaedische Industrie Besitz- und Verwaltungs-Kommanditgesel lschaft Orthopaedic connection
EP1806155A2 (fr) 2006-01-05 2007-07-11 Howmedica Osteonics Corp. Procédé de fabrication d'un composant d'implant médical et tel composant.
EP1808186A2 (fr) * 2006-01-05 2007-07-18 Howmedica Osteonics Corp. Composant d'un implant médical et son procédé de préparation
DE102006013115A1 (de) * 2006-03-22 2007-09-27 omt Oberflächen- und Materialtechnologie GmbH Verfahren zur Herstellung heller biokompatibler Schichten auf Implantatkörpern
DE102017111784A1 (de) 2017-05-30 2018-12-06 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Beschichtetes Substrat mit titanhaltiger Beschichtung und modifizierter Titanoxidbeschichtung

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115466944B (zh) * 2022-08-26 2023-07-25 中南大学湘雅医院 一种陶瓷材料及其制备方法

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1986006617A1 (fr) * 1985-05-07 1986-11-20 Plasmainvent Ag Revetement d'un corps d'implant

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1986006617A1 (fr) * 1985-05-07 1986-11-20 Plasmainvent Ag Revetement d'un corps d'implant

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1991003266A1 (fr) * 1989-08-31 1991-03-21 Böhler Ag Prothese
DE4005692A1 (de) * 1990-02-23 1991-08-29 Omt Oberflaechen Materialtech Verfahren zur herstellung von physiologisch vertraeglichen oxidschichten auf skelettimplantaten
EP0613667A1 (fr) * 1993-03-05 1994-09-07 SMITH & NEPHEW RICHARDS, INC. Implant fémoral de genou en matière plastique
US5976190A (en) * 1996-11-06 1999-11-02 Otto Bock Orthopaedische Industrie Besitz- und Verwaltungs-Kommanditgesel lschaft Orthopaedic connection
EP1806155A2 (fr) 2006-01-05 2007-07-11 Howmedica Osteonics Corp. Procédé de fabrication d'un composant d'implant médical et tel composant.
EP1808186A2 (fr) * 2006-01-05 2007-07-18 Howmedica Osteonics Corp. Composant d'un implant médical et son procédé de préparation
EP1808186A3 (fr) * 2006-01-05 2007-10-10 Howmedica Osteonics Corp. Composant d'un implant médical et son procédé de préparation
EP1806155A3 (fr) * 2006-01-05 2007-10-10 Howmedica Osteonics Corp. Procédé de fabrication d'un composant d'implant médical et tel composant.
US8187660B2 (en) 2006-01-05 2012-05-29 Howmedica Osteonics Corp. Method for fabricating a medical implant component and such component
DE102006013115A1 (de) * 2006-03-22 2007-09-27 omt Oberflächen- und Materialtechnologie GmbH Verfahren zur Herstellung heller biokompatibler Schichten auf Implantatkörpern
DE102017111784A1 (de) 2017-05-30 2018-12-06 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Beschichtetes Substrat mit titanhaltiger Beschichtung und modifizierter Titanoxidbeschichtung
WO2018220002A1 (fr) 2017-05-30 2018-12-06 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung eingetragener Verein Substrat revêtu présentant un revêtement contenant du titane et revêtement d'oxyde de titane modifié

Also Published As

Publication number Publication date
EP0348389A1 (fr) 1990-01-03

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