1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 20795-2:2013Part 2: Orthodontic base polymersDentistry Base polymers BS EN ISO 20795-2:2013 BRITISH STANDARDNational forewordThis British Standard is the UK implementat
2、ion of EN ISO 20795-2:2013. It supersedes BS EN ISO 20795-2:2010 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee CH/106/2, Prosthodontic materials.A list of organizations represented on this committee can be obtained on request to its secretary.This pu
3、blication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2013. Published by BSI Standards Limited 2013ISBN 978 0 580 79562 6 ICS 11.060.10 Compliance with a British Standard cannot confer im
4、munity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 March 2013.Amendments issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 20795-2 March 2013 ICS 11.060.
5、10 Supersedes EN ISO 20795-2:2010English Version Dentistry - Base polymers - Part 2: Orthodontic base polymers (ISO 20795-2:2013) Mdecine bucco-dentaire - Polymres de base - Partie 2: Polymres pour base orthodontique (ISO 20795-2:2013) Zahnheilkunde - Kunststoffe - Teil 2: Kieferorthopdische Kunstst
6、offe (ISO 20795-2:2013) This European Standard was approved by CEN on 5 February 2013. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists
7、 and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under t
8、he responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugo
9、slav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN
10、 DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2013 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 20795-2:2013: EBS EN ISO 20795-2:2013EN ISO 20795-2:2013 (E) 3 Foreword
11、This document (EN ISO 20795-2:2013) has been prepared by Technical Committee ISO/TC 106 “Dentistry“ incollaboration with Technical Committee CEN/TC 55 “Dentistry” the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication o
12、f an identicaltext or by endorsement, at the latest by September 2013, and conflicting national standards shall bewithdrawn at the latest by September 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject of patentrights. CEN and/or CENELEC shall n
13、ot be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 20795-2:2010. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulg
14、aria, Croatia, Cyprus, CzechRepublic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turke
15、y and the United Kingdom. Endorsement notice The text of ISO 20795-2:2013 has been approved by CEN as EN ISO 20795-2:2013 without any modification. BS EN ISO 20795-2:2013ISO 20795-2:2013(E) ISO 2013 All rights reserved iiiContents PageForeword ivIntroduction v1 Scope . 12 Normative references 13 Ter
16、ms and definitions . 14 Classification 25 Requirements 25.1 Unpolymerized material . 25.2 Polymerized material 36 Sampling 57 Preparation of specimen plates and test specimens . 57.1 Laboratory environment 57.2 Procedures 57.3 Special equipment 58 Test methods . 58.1 Inspection for compliance determ
17、ination . 58.2 Colour 68.3 Polishability, freedom from porosity, ultimate flexural strength, and flexural modulus . 68.4 Fracture toughness with a modified bending test .108.5 Residual methyl methacrylate monomer 148.6 Plasticiser(s), where applicable 198.7 Water sorption and solubility . 239 Requir
18、ements for labelling, marking, packaging, and instructions supplied by manufacturer 269.1 Packaging 269.2 Marking of outer packages and containers . 269.3 Manufacturers instructions . 27Annex A (normative) HPLC method for determination of MMA content .28Bibliography .31BS EN ISO 20795-2:2013ISO 2079
19、5-2:2013(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for
20、 which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on a
21、ll matters of electrotechnical standardization.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are c
22、irculated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held respo
23、nsible for identifying any or all such patent rights.ISO 20795-2 was prepared by Technical Committee ISO/TC 106, Dentistry, Subcommittee SC 2, Prosthodontic materials.This second edition cancels and replaces the first edition (ISO 20795-2:2010), which has been technically revised.ISO 20795 consists
24、of the following parts, under the general title Dentistry Base polymers: Part 1: Denture base polymers Part 2: Orthodontic base polymersiv ISO 2013 All rights reservedBS EN ISO 20795-2:2013ISO 20795-2:2013(E)IntroductionPolymeric materials based on methacrylates have been widely used in the construc
25、tion of both active and passive removable orthodontic appliances for many years. These removable appliances are mainly used in the orthodontic treatment of children. The method of preparing the polymeric part of the orthodontic appliance has several potential problems. Depending on the polymerizatio
26、n process and polymer/monomer mixing ratio, the polymer part of the removable orthodontic appliance may be weaker than if conventional flasking and heat systems of polymerization were used. There may be a greater risk that an appliance will have more residual substances such as monomers than a conve
27、ntional heat-cured denture base polymer. In addition, a high monomer content of the polymer/monomer mix may cause increased contraction on polymerization.Specific qualitative and quantitative requirements for freedom from biological hazard are not included in this part of ISO 20795, but it is recomm
28、ended that, in assessing possible biological or toxicological hazards, reference be made to ISO 10993-1 and ISO 7405. ISO 2013 All rights reserved vBS EN ISO 20795-2:2013BS EN ISO 20795-2:2013Dentistry Base polymers Part 2: Orthodontic base polymers1 ScopeThis part of ISO 20795 is applicable to orth
29、odontic base polymers and copolymers used in the construction of both active and passive orthodontic appliances and specifies their requirements. It also specifies test methods to be used in determining compliance with these requirements. It further specifies requirements with respect to packaging a
30、nd marking the products and to the instructions to be supplied for use of these materials.2 Normative referencesThe following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition
31、of the referenced document (including any amendments) applies.ISO 1942, Dentistry VocabularyISO 3696, Water for analytical laboratory use Specification and test methodsISO 7491, Dental materials Determination of colour stabilityISO 8601, Data elements and interchange formats Information interchange
32、Representation of dates and timesISO 20795-1:2008, Dentistry Base polymers Part 1: Denture base polymers3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 1942 and the following apply.3.1autopolymerizable materialsproducts having polymerization initiated
33、 by chemical means and not requiring application of temperatures above 65 C to complete the polymerization3.2build up techniquespray on techniquegradual addition of increments of powder and liquid on the master cast until the desired shape is attained3.3immediate containercontainer that is in direct
34、 contact with the orthodontic base materials3.4light activated polymersproducts having polymerization initiated by the application of energy from an external radiation source, such as visible lightINTERNATIONAL STANDARD ISO 20795-2:2013(E) ISO 2013 All rights reserved 1BS EN ISO 20795-2:2013ISO 2079
35、5-2:2013(E)3.5liquidmonomeric liquid to be mixed with polymeric particles to form a mouldable dough or fluid resin mixture used for forming orthodontic bases3.6orthodontic basepolymer part of the orthodontic appliance3.7outer packaginglabelled container or wrapping within which other containers are
36、packed3.8powderpolymeric particles to be mixed with monomeric liquid to form a mouldable dough or fluid resin mixture used for forming orthodontic bases3.9processingprocedure of preparing a solid orthodontic base polymer plate and/or specimen by polymerization or injection3.10thermoplastic materialh
37、ard orthodontic polymeric material that can be softened by application of heat to make it mouldable, and then returned to the hardened state upon cooling4 ClassificationOrthodontic base polymers covered by this part of ISO 20795 are categorized into the following types: Type 1: autopolymerizable mat
38、erials; Type 2: light-activated materials; Type 3: thermoplastic materials.5 Requirements5.1 Unpolymerized material5.1.1 Liquid component5.1.1.1 GeneralThe liquid shall consist essentially of monomeric material compatible with the powder.5.1.1.2 HomogeneityThe liquid shall be free of deposit or sedi
39、ment that can be observed by visual inspection (see 8.1.1).5.1.2 Solid componentsThe solid or semi-solid components shall be free of extraneous material that can be observed by visual inspection (see 8.1.1).2 ISO 2013 All rights reservedBS EN ISO 20795-2:2013ISO 20795-2:2013(E)5.2 Polymerized materi
40、al5.2.1 BiocompatibilitySpecific qualitative and quantitative requirements for freedom from biological hazard are not included in this part of ISO 20795, but it is recommended that, in assessing possible biological or toxicological hazards, reference be made to ISO 10993-1 and ISO 7405.5.2.2 Surface
41、 characteristics5.2.2.1 When processed in the manner recommended by the manufacturer and in contact with materials recommended by the manufacturer, orthodontic base polymer test specimens prepared in accordance with 8.5.2 and 8.6.3 shall have a smooth, hard, and glossy surface (see 8.1.1).5.2.2.2 Th
42、e test specimens for residual methyl methacrylate monomer (see 8.5) and the specimens for water sorption and solubility testing (see 8.7) shall retain their form without visible distortion after processing (see 8.1.1).5.2.2.3 When polished in accordance with 8.3.1.4, the specimen plates shall presen
43、t a smooth surface with a high gloss (see 8.1.1).5.2.3 Shape capabilityWhen prepared in accordance with the manufacturers instructions, all types of orthodontic base polymers shall produce a test specimen plate (see 8.3.1.4) with defined edges and dimensions as given in Figure 1.Dimensions in millim
44、etresNOTE Dimensional tolerance shall be 1 mm.Figure 1 Model of the specimen plate (see 8.3.1.2.1)5.2.4 ColourThe colour of a test specimen strip prepared in accordance with 8.3.2.3 shall be as stated by the manufacturer when tested and inspected in accordance with 8.1.1 and 8.2.Coloured orthodontic
45、 base polymers shall be evenly pigmented and/or coloured. ISO 2013 All rights reserved 3BS EN ISO 20795-2:2013ISO 20795-2:2013(E)Transparent orthodontic base polymers shall be transparent or clear.5.2.5 Freedom from porosityWhen prepared in accordance with 8.3.2.3, the test specimen strips shall not
46、 show pores that can be observed by visual inspection (see 8.1.1).5.2.6 Ultimate flexural strengthWhen determined in accordance with 8.3.2.5, the ultimate flexural strength shall be not less than 50 MPa (see Table 1).5.2.7 Flexural modulusWhen determined in accordance with 8.3.2.5, the flexural modu
47、lus of the processed orthodontic base polymer shall be at least 1 500 MPa (see Table 1).5.2.8 Maximum stress intensity factorWhen determined in accordance with 8.4, the maximum stress intensity factor shall be at least 1,1 MPam1/2(see Table 1).5.2.9 Total fracture workWhen determined in accordance w
48、ith 8.4, the total fracture work shall be at least 250 J/m2(see Table 1).5.2.10 Residual methyl methacrylate monomerWhen orthodontic base polymers are prepared and tested in accordance with 8.5, the following shall apply (see Table 1).The maximum mass fraction of residual methyl methacrylate is 5 %
49、for all three types of orthodontic base polymers.The residual methyl methacrylate content claimed by the manufacturer see 9.3 b) shall not exceed the stated value by more than 0,2 % mass fraction when tested in accordance with 8.5.5.2.11 PlasticizersIf the orthodontic base polymer contains extractable phthalate plasticizer(s), identify and quantify the plasticizer(s) as percent mass fraction determined in accordance with 8.6. The content shall not exceed the stated value by more than 10 % (see Table 1).5.2.12 W
