1、Designation: F451 08F451 16Standard Specification forAcrylic Bone Cement1This standard is issued under the fixed designation F451; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision.Anumber in parentheses ind
2、icates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers self-curing resins used primarily for the fixation of internal orthopedic prostheses. The mixturemay be used in either the predough or d
3、ough stage in accordance with the manufacturersmanufacturers recommendations.1.2 Units of premeasured powder and liquid are supplied in a form suitable for mixing. The mixture then sets in place.1.3 While a variety of copolymers and comonomers may be incorporated, the composition of the set cement s
4、hall containpoly(methacrylic acid esters) as its main ingredient.1.4 This specification covers compositional, physical performance, and biocompatibility as well as packaging requirements. Thebiocompatibility of acrylic bone cement as it has been traditionally formulated and used has been reported in
5、 the literature (1, 2).21.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this
6、 standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D638 Test Method for Tensile Properties of PlasticsD695 Test Method for Compressive Properties of Rigid PlasticsD1193 Specif
7、ication for Reagent WaterD3835 Test Method for Determination of Properties of Polymeric Materials by Means of a Capillary RheometerD1193 Specification for Reagent WaterF619 Practice for Extraction of Medical PlasticsF748 Practice for Selecting Generic Biological Test Methods for Materials and Device
8、sF749 Practice for Evaluating Material Extracts by Intracutaneous Injection in the RabbitF756 Practice for Assessment of Hemolytic Properties of MaterialsF763 Practice for Short-Term Screening of Implant MaterialsF813 Practice for Direct Contact Cell Culture Evaluation of Materials for Medical Devic
9、esF895 Test Method for Agar Diffusion Cell Culture Screening for CytotoxicityF981 Practice for Assessment of Compatibility of Biomaterials for Surgical Implants with Respect to Effect of Materials onMuscle and Insertion into Bone2.2 ANSI/ADA Standard:No. 15 Specification for Acrylic Resin Teeth43. T
10、erminology3.1 Definitions of Terms Specific to This Standard:1 This specification is under the jurisdiction of ASTM Committee F04 on Medical and Surgical Materials and Devices and is the direct responsibility of SubcommitteeF04.11 on Polymeric Materials.Current edition approved Aug. 1, 2008Oct. 1, 2
11、016. Published September 2008December 2016. Originally approved in 1976. Last previous edition approved in 20072008as F451 99a (2007)F451 08.1. DOI: 10.1520/F0451-08.10.1520/F0451-16.2 The boldface numbers in parentheses refer to the list of references at the end of this standard.3 For referencedAST
12、M standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4
13、th Floor, New York, NY 10036, http:/www.ansi.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurat
14、ely, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
15、13.1.1 doughing timethe time after commencement of mixing at which the mixture ceases to adhere to a standard probe (see7.5).3.1.2 exothermic or maximum temperaturethe maximum temperature of the mixture due to self-curing in a standard mold (see7.6).3.1.3 extrusionthe rate of flow of the material th
16、rough a standard orifice under load (see 7.8.1).3.1.4 intrusionthe distance of flow of the mixture into a standard mold under load (see 7.8.3).3.1.5 setting timethe time after commencement of mixing at which the temperature of the curing mass equals the average ofthe maximum and ambient temperatures
17、 (see 7.7).3.1.6 unitone package or vial of premeasured powder component and one package or vial of premeasured liquid component.4. Physical Requirements4.1 Liquid:4.1.1 AppearanceThe liquid shall be free of extraneous particulate matter or obvious visual contaminants in its container.4.1.2 Stabilit
18、yAfter being heated for 48 h at 60 6 2C, the viscosity of the liquid shall not increase by more than 10 % ofits original value (see 7.3).4.1.3 SterilityThe liquid, as poured from its container, shall pass the tests described in “Sterility TestsLiquid andOintments” (7.4) (3).4.2 Powder:4.2.1 Appearan
19、ceThe powder shall be pourable and free of extraneous materials, such as dirt or lint (7.2.2).4.2.2 SterilityThe powder, as poured from its package, shall pass the tests described in “Sterility TestsSolids” (7.4) (2).4.3 Powder-Liquid Mixture:4.3.1 If the mixture is to be used in its predough stage,
20、 the material shall conform to the properties given in Table 1.4.3.2 If the mixture is to be used in its dough stage, the material shall conform to the properties given in Table 1.4.3.3 If the mixture can be used in either its predough or dough stages, separate units must be tested for compliance wi
21、th 4.3.1and 4.3.2.4.4 Cured PolymerThe material after setting shall conform to the properties given in Table 2.5. Weights and Permissible Variations5.1 Weight and volume measurements shall be made on the respective powder and liquid components of five units (see 3.1).These units may be subsequently
22、utilized in any of the nonsterile tests of this specification.5.2 The weights, or volume of the powder and liquid components, or both, shall not deviate by more than 5 % from those statedon the package (9.2.2), of each of five units.5.3 Where a radiopaque material is supplied for addition to the pow
23、der at the discretion of the surgeon, the weight or volumepercent of the radiopaque material shall not deviate by more than 15 % from the value stated on the package (9.2.3).6. Sampling6.1 Units of powder and liquid shall be procured to provide sufficient material for all the tests of this specifica
24、tion. The unitsshall be obtained from regular retail distribution channels. Provided no repeat tests are required, this will amount to between sevenand ten units.6.2 It will only be necessary to maintain sterility in tests described in 7.4.All other tests described in this specification need notbe c
25、onducted under sterile conditions.7. Test Methods and Sample Size7.1 Maintain all equipment, mixing surfaces, and materials at 23 6 2C at least 2 h prior to testing and conduct all tests at 236 2C and 50 6 10 % relative humidity unless otherwise specified.7.2 InspectionUse visual inspection in deter
26、mining compliance to the requirements outlined in 4.1.1, 4.2.1, 8.1 and 8.2.TABLE 1 Requirements for Powder Liquid MixturePropertyProperty Extrusion,Viscosity TestsDough Usage,IntrusionTestsMax Dough Time, min. 5.0 5.0Setting Time Range, min. 5 to 15 5 to 15Temperature, max., C 90 90Intrusion, min.,
27、 mm . 2.0F451 1627.2.1 The liquid component of two separate units shall comply with the requirements of 4.1.1 and 8.1.7.2.2 The powder component of two separate units shall comply with the requirements of 4.2.1 and 8.1.7.3 Liquid Component ViscosityRecord the viscosity change of two separate units (
28、4.1.2) before and after the heating exposureby timing the flow of the liquid level between the 0 and 5 mL marks of a 10 mL measuring pipet. Calculate the percent changeas follows:% Change5ta 2t btb 3100 (1)where:tb = flow time before heating, andta = flow time after heating exposure (4.1.2) of 60 6
29、2C for 48 h in the dark in a closed container.7.3.1 An alternative method for viscosity may be used if it can be demonstrated to yield similar results. Both shall comply tothe less than 10 % change specified (4.1.2).7.4 The components of the two units shall be tested for sterility in accordance with
30、 the test methods described in U.S.Pharmacopoeia, “Sterility Tests” (3).7.5 Doughing Time:7.5.1 EnvironmentAll equipment, mixing surfaces, and material (unit size) shall be maintained at 23 6 1C at least 2 h priorto testing and tests shall be conducted at 23 6 1C. The relative humidity shall be 50 6
31、 10 %.7.5.2 Mix all the powder and liquid of a single unit together as directed by the manufacturers instructions (see 8.2). Start a stopwatch at the onset of combining the liquid to the powder and read all subsequent times from this stop watch. Approximately 1.5min after the onset of mixing, gently
32、 probe the mixture with a non-powdered surgically gloved (latex) finger. Take visual noticeas to the formation of fibers between the surface of the mix and the finger as it leaves the surface. Repeat this process from thattime on at 15 s intervals with a clean portion of the glove until the gloved f
33、inger separates cleanly. Denote the time at which thisis first observed as the doughing time. Mix the mixture between determinations to expose fresh material for each probing.7.5.3 Determine the average doughing time from two separate units.7.5.4 The two values found shall agree within 30 s of each
34、other, otherwise repeat the test on two additional units. Report theaverage of all four tests and the range of values.7.5.5 Report the doughing time to the nearest 15 s as the average of all determinations. Maximum and minimum values ofdoughing times measured shall not differ by more than 6112 min f
35、rom the average.7.5.6 Report the brand of non-powdered surgical glove used for dough time determinations. It is necessary that the type of glovebe described in detail, including manufacturer, when the dough time is reported.7.6 Exothermic TemperatureWithin 1 min after doughing time, gently pack appr
36、oximately 25 g of the dough described in 7.5into the mold described in Fig. 1. This mold shall be made of polytetrafluoroethylene (PTFE), poly(ethyleneterephthalate),polyoxymethylene, high density polyethylene, or ultra-high molecular weight polyethylene (UHMWPE) and be equipped with aNo. 24 gage wi
37、re thermocouple, or similar device, positioned with its junction in the center of the mold at a height of 3.0 mm inthe internal cavity. Immediately seat the plunger with a C-clamp or suitable press to produce the 6.0 mm specimen height. Uponproducing plunger seating, remove the excess material and t
38、he C-clamp or press for the remainder of the procedure. Continuouslyrecord the temperature with respect to time from the onset of mixing the liquid and the powder until cooling is observed, Fig. 2.Report the maximum temperature recorded to the nearest 1C. This should not exceed the value given in Ta
39、ble 1.7.6.1 The maximum temperature shall be the average of two separate determinations reported to the nearest 1C.7.6.2 If the difference between the maximum temperature for the two determinations is greater than 5.0C, repeat the test ontwo additional units and report the average of all four runs t
40、o the nearest 1C. Individual maximum and minimum values formaximum temperature shall not differ by more than 64C of the average value of all determinations.7.7 Setting TimeFrom the continuous time versus temperature recording of 7.6, the setting time (Tset) is the time when thetemperature of the pol
41、ymerizing mass is as follows:Tmax1Tamb!/2 (2)where:Tmax = maximum temperature, C, andTamb = ambient temperature of 23 6 1C.TABLE 2 Requirements for Cured Polymer After SettingProperty RequirementProperty RequirementCompressive Strength,min., MPa70F451 1637.7.1 Report the setting time to the nearest
42、5 s.7.7.2 Make two separate determinations of the setting time.NOTE 1Dimensions in millimetres and 60.2 unless otherwise specified. Material for all components: Polytetrafluoroethylene,poly(ethyleneterephthalate), polyoxymethylene, high density polyethylene, or ultra-high molecular weight polyethyle
43、ne (UHMWPE).FIG. 1 Exothermic Heat MoldFIG. 2 Continuous Temperature RecordF451 1647.7.3 The two values should agree within 1 min of each other, otherwise repeat the test on two additional units and report theaverage of all runs.7.7.4 Report the setting time to the nearest 15 s as the average of all
44、 determinations.7.8 Flow Properties and Viscosity DeterminationThe manufacturer must specify whether the cement may be used in itspre-dough or dough state, or both. The determination of its usage dictates which of the following tests the cement should complywith. If the mixture is to be utilized in
45、the pre-dough stage, use the extrusion viscosity test (7.8.1 and/or 7.8.2) and Table 1. If themixture is to be utilized in the dough stage, use the intrusion test (7.8.3) and Table 1. If the mixture is to be used as a dual usagecement, then both the extrusion (7.8.1 and/or 7.8.2) and intrusion (7.8.
46、3) tests must be performed.7.8.1 Extrusion, Capillary Viscosity:7.8.1.1 Apparatus:(1) Capillary RheometerAny capillary rheometer is satisfactory in which acrylic bone cement can be forced from a reservoirthrough a capillary die and in which temperature, applied force, output rate, and barrel and die
47、 dimensions can be controlled andmeasured accurately. Equipment that provides a constant shear rate has been shown to be equally useful. The capillary die of therheometer shall have a smooth straight bore that is held within 60.0076 mm (60.0003 in.) in diameter and shall be held to within60.025 mm (
48、60.001 in.) in length. The bore and its finish are critical. It shall have no visible drill or other tool marks and nodetectable eccentricity.(2) Due to the extreme sensitivity of flow data to the capillary dimensions, it is important that the capillary dimensions aremeasured with precision and repo
49、rted. The length to diameter ratio shall normally be between 20 and 40. Larger ratios and ratiosless than that suggested require applying large corrections to the data (4, 5). In addition, the ratio of the reservoir diameter tocapillary diameter should be between 3 and 15. See Test Method D3835 for further details of capillary rheometers.7.8.1.2 CalibrationPerform the test with a certified standard viscosity fluid approximating that expected for bone cement (50Ns/m2 to 500 Ns/m2). Determine the viscosity of the standard fluid and
