1、Designation: F 754 08Standard Specification forImplantable Polytetrafluoroethylene (PTFE) Sheet, Tube, andRod Shapes Fabricated from Granular Molding Powders1This standard is issued under the fixed designation F 754; the number immediately following the designation indicates the year oforiginal adop
2、tion or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification describes the physical, chemical, andmechanical perfo
3、rmance requirements for polytetrafluoroeth-ylene (PTFE) pre-fabricated by compression molding or extru-sion into sheet, tube, and rod shapes which may be used forimplant products.1.2 PTFE is a high molecular weight straight chain memberof the generic class of perfluorocarbon (containing only theelem
4、ents fluorine and carbon) polymers.1.3 Perfluorocarbon high polymers exhibit extraordinarythermal and chemical stability and do not require stabilizingadditives of any kind.1.4 This specification applies to primarily void-free moldedor extruded PTFE shapes formed from granular moldingpowders. This s
5、pecification does not apply to shapes formedfrom “fine powder” resins by lubricated paste extrusion, whichincludes expanded PTFE.1.5 This specification does not apply to specific surgicalimplant products, including their packaging, sterilization, ormaterial boicompatibility and/or suitability for a
6、particularend-use application.1.6 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of t
7、his standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1710 Specification for Extruded Polytetrafluoroethylene(PTFE) Rod, Heavy Walled Tubing and Basic ShapesD 3294 Specif
8、ication for Polytetrafluoroethylene (PTFE)Resin Molded Sheet and Molded Basic ShapesD 4894 Specification for Polytetrafluoroethylene (PTFE)Granular Molding and Ram Extrusion MaterialsE 1994 Practice for Use of Process Oriented AOQL andLTPD Sampling Plans2.2 AAMI Standards:3AAMI STBK91 SterilizationP
9、art 1: Sterilization inHealth Care FacilitiesAAMI STBK92 SterilizationPart 2: Sterilization Equip-mentAAMI STBK93 SterilizationPart 3: Industrial ProcessControl2.3 ANSI Standards:4ANSI/ISO/ASQ Q9000 Quality Management SystemsFundamentals and VocabularyANSI/ISO/ASQ Q9001 Quality Management SystemsReq
10、uirements2.4 ISO Standards:4ISO 10993 Biological Evaluation of Medical Devices2.5 U. S. Code of Federal Regulations:521 CFR 820 Quality System Regulation2.6 U. S. Pharmacopeia (USP) Standards:6USP30/NF25 Sterilization and Sterility Assuranceof Compendial Articles3. Significance and Use3.1 Fabricated
11、 PTFE meeting the requirements of this speci-fication can be expected to exhibit consistent and reproduciblechemical, physical, and biological properties.3.1.1 This specification provides an analytic method to1This specification is under the jurisdiction of ASTM Committee F04 onMedical and Surgical
12、Materials and Devices and is the direct responsibility ofSubcommittee F04.11 on Polymeric Materials.Current edition approved Oct. 1, 2008. Published November 2008. Originallyapproved in 1983. Last previous edition approved in 2000 as F 754 00.2For referenced ASTM standards, visit the ASTM website, w
13、ww.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Association for the Advancement of Medical Instrumentation(AAMI), 1110 N. Glebe Rd., Suite 220, Arling
14、ton, VA 222014795.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.5Available from U.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.
15、gpo.gov.6Available from U.S. Pharmacopeia (USP), 12601 Twinbrook Pkwy., Rockville,MD 20852-1790, or through http:/www.usp.org/products/USPNF/. The standardswill be listed by appropriate USP citation number. Succeeding USP editionsalternately may be referenced.1Copyright ASTM International, 100 Barr
16、Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.extract organic contaminants from fabricated configurations,which includes a limit to the presence of residual adulterants,additives, or processing aids.3.1.2 This specification addresses the characteristics ofvirgin raw gran
17、ular molding powders obtained from resinmanufacturers and used for producing implant configurations.4. Physical Property Requirements4.1 Molding and Extrusion Powders:4.1.1 PTFE PolymerGranular molding and extrusionpowders used for fabrication of implant configurations shall bevirgin product and sha
18、ll conform to Specification D 4894.4.2 PTFE Standard Shapes:4.2.1 Standard shapes, such as molded sheet, rod, and/ortube utilized in implants, shall have been prepared from virginmolding or extrusion materials which meet the provisions of4.1.1.4.2.2 PTFE molded sheet shall comply with Type I, Grade
19、I,Class A requirements in Specification D 3294.4.2.3 PTFE rod and/or tube in the final implant shape shallcomply with Type I, Grade I, Class D specifications inSpecification D 1710. Material purchased for conversion into afinal implant shape may meet Classes A, B, C, or D.4.2.4 The final implant man
20、ufacturer shall determine if thespecified dimensions and mechanical properties of thesupplier-provided and/or as-converted sheet, rod, and/or tubeare appropriate for the intended implant application.Additionalmaterial property data (such as fatigue life, wear, and abrasionresistance) may also be nec
21、essary to assure suitability, depen-dent on the implant application.4.3 Surface ContaminationThe surface of a fabricatedshape shall not contain particles or residue of a diametergreater than 300 m. The concentration of visible particlesunder 83 magnification shall not be greater than 10 particlesper
22、 400 cm2.4.4 Physical properties for other than standard shapes arenot encompassed by this specification and must be addressedby appropriate performance standards for given configurations.5. Chemical Property Requirements5.1 Carbon Tetrachloride ExtractionThe supplier-provided or as-converted final
23、PTFE implant shapes shall besampled in accordance with Practice E 1994 (or equivalentstandard guidance) and extracted with carbon tetrachloride bythe method described in Annex A1.5.1.1 Extractable HydrocarbonsThe absence of extract-able hydrocarbons shall be demonstrated by infrared analysisof the c
24、arbon tetrachloride extract using the methodology andacceptance criteria described in Annex A1.5.1.2 AppearanceA sample shall be examined under day-light conditions with the naked eye immediately followingcarbon tetrachloride extraction as described in Annex A1. Thissample while still wet with carbo
25、n tetrachloride shall not beapparently changed in size or consistency. When dried for 4 hin a 100C air-circulating oven, the appearance of the extractedpolymer sample shall be unchanged as compared to an unex-tracted specimen.5.2 Extraction with Distilled WaterFinal PTFE implantshapes sampled from s
26、tock shall be extracted with distilledwater by the methodology described in Annex A2.5.2.1 Extractable ElectrolytesThe resistivity of the wateras measured by a resistivity conductivity meter shall be greaterthan 0.05 MVcm.5.2.2 AppearanceWhen examined by unaided vision indaylight, the appearance of
27、PTFE sampled from stock imme-diately following water extraction shall be unchanged exceptfor being obviously wet with water. When dried for 4 h at100C in an air-circulating oven the appearance shall beunchanged from pre-extraction appearance.6. Manufacturing Control, Sterilization, andBiocompatibili
28、ty6.1 Any final implant product needs to be manufacturedunder an acceptable level of control and provided both insterile form and with a level of biocompatibility suitable for thefinal implant application.6.2 Acceptable levels of manufacturing control are likely tobe required for commercial distribu
29、tion. General guidelines forachieving acceptable levels of manufacturing quality controlmay be found in the following standards:6.2.1 United States Code of Federal Regulations (CFR), 21CFR 820.6.2.2 ANSI/ISO/ASQ Q9000Provides fundamentals forquality management systems as described in the ISO 9000fam
30、ily (informative); and specifies quality management termsand their definitions (normative).6.2.3 ANSI/ISO/ASQ Q9001Presents requirements for aquality management system. The application of this guide canbe used by an organization to demonstrate its capability to meetcustomer requirements for products
31、 or services, and for assess-ment of that capability by internal and external parties.6.3 A summary of most common sterilization methods,testing, and quality assurance can be found in USP30/NF25. AAMI maintains a 3-volume set of sterilizationstandards and recommended practices containing 46 differen
32、tstandards: AAMI STBK91, AAMI STBK92, and AAMISTBK93.NOTE 1Since many fluoropolymers can be readily damaged and/oraltered by radiation-based sterilization, significant caution should beundertaken when considering such methods.6.4 Finished device biocompatibility can be ascertainedthrough evaluation
33、utilizing the guidelines detailed withinISO 10993.6.4.1 A brief summary of in vivo particulation concernsspecific to mechanically loaded PTFE may be found inAppendix X2.7. Keywords7.1 perfluorocarbon; polytetrafluoroethylene; PTFE; surgi-cal implantF754082ANNEXES(Mandatory Information)A1. INFRARED A
34、NALYSIS OF HYDROCARBONS EXTRACTABLE IN CARBON TETRACHLORIDEA1.1 Stir at least1gofchopped sample, all of which passesa No. 40 mesh screen, for 30 min with 7-mL of reagent-gradecarbon tetrachloride. When decanted, the carbon tetrachlorideshall be clear and colorless.A1.2 Perform infrared analysis of t
35、he carbon tetrachlorideafter placement within a 10 by 10 mm silica quartz UV cuvette(for example, Beckman-Coulter Part No. 580012).A1.2.1 The requirements of this analysis shall be satisfiedwhen transmission between 3 and 4 m is essentially 100 % forthe reagent grade control and at least 95 % of tha
36、t of the controlscan for carbon tetrachloride in which the chopped sample wasstored.A2. EXTRACTION WITH WATER FOR ELECTROLYTESA2.1 The specimens shall be cubes or rectangles with noedge dimension greater than 1 cm. The total specimen weightshall be 10 6 1g.A2.2 Place the specimens in a suitable cont
37、ainer, such as a100-cm3suction flask, along with 50 mL of distilled water.Store the flask 48 h at ambient temperature.A2.3 After 48 h, decant the water. The water shall remainclear and colorless. The extractable electrolyte requirementsshall be satisfied when the resistivity of the water is greatert
38、han 0.05 MVcm.APPENDIXES(Nonmandatory Information)X1. STATEMENT OF RATIONALEX1.1 This specification was established to provide guid-ance in the testing of polytetrafluorethylene intended for use inmedical device applications. It recommends test methods forthe measurement of chemical, physical and me
39、chanical prop-erties of unfabricated and fabricated forms. Tests should beselected according to end-use applications. It is intended thatbiocompatibility be established on the finished product by theappropriate procedures, after it has gone through all processingsteps.X1.2 The scope section of this
40、document defines the term“PTFE” and limits the specific scope of the document tofabricated sheet, tube, and rod shapes. It further makes clearthat the specification does not apply to specific surgical implantproducts that would be subject to appropriate specific end-useperformance standards. This se
41、ction emphasizes the extraordi-nary chemical and thermal stability and inherent absence ofadditives in PTFE; these factors are no doubt responsible forthe large bibliography of successful implant use for thispolymer in the absence of any previous implant grade specifi-cation guidance.X1.3 The signif
42、icance section sets out the capability of thisstandard by ensuring consistent and reproducible behavior.X2.1 explains the caution against construing this specificationfor applications where particulate debris may be anticipated.X1.4 In 4.1, the specific raw polymer properties consistentwith the scop
43、e and intent of this specification are defined interms of existingASTM specifications so that the raw polymerswill be virgin products providing the highest purity availableunder current manufacturing technology. Similarly, 4.2 relatesthe finished shape physical properties consistent with the scopean
44、d objectives of this standard specification to existing ASTMspecifications for such standard shapes. These requirementswould provide the superior properties for such shapes availablewith current fabrication technology.X1.5 Section 5 provides appearance and extractable criteriafor PTFE-fabricated sha
45、pes sampled from stock to establish theabsence of extractable organic or electrolytic contaminants thatmay have contaminated the product during its preparation. Afailure would then signal the need for review of the manufac-turing process to determine the nature, source, and significanceof the contam
46、ination.F754083X2. BIOCOMPATIBILITYX2.1 PTFE configurations were first used for implantationin the early 1950s and, in numerous applications, have servedas compatible implants in large numbers of patients, with someimplant durations beyond 20 years (1, 2, 3).7However, use ofPTFE in in vivo applicati
47、ons with load bearing outside of thepressure-velocity (PV) limits for the polymer may result insignificant particulation and extensive adverse effects (4, 5).Abrief summary of adverse effects from the historical use ofPTFE in the temporomandibular joint application can be foundin the document entitl
48、ed TMJ ImplantsA Consumer Infor-mational Update.8X2.2 No known surgical implant material has ever beenshown to be completely free of adverse reactions in the humanbody. However, long term clinical experience of use of specificcompositions and formations of this material referred to in thisstandard h
49、as shown that an acceptable level of biologicalresponse can be expected, if the material is used in appropriateapplications.REFERENCES(1) Homsy, C. A., “Biocompatibility of Perfluorinated Polymers andComposites of These Polymers,” Biocompatibility of Clinical ImplantMaterials, O.F. Williams, ed., Chap. 3, Vol II, Boca Raton, FL, C.R.C.Press, Inc., 1982, pp 5977.(2) Sanchez, L. A., Snuggs, W. D., Veith, F. J., Marin, M. L., Wengerter,K. R., Panetta, T. F., “Is Surveillance to Detect Failing Polytetrafluo-roethylene Bypasses Worthwhile?: Twelve-year E
