EN 26873:1991
(Main)Dentistry - Dental gypsum products (ISO 6873:1983)
Dentistry - Dental gypsum products (ISO 6873:1983)
Zahnheilkunde - Dentalgipse (ISO 6873:1983)
Art dentaire - Produits dentaires à base de gypse (ISO 6873:1983)
Dentistry - Dental gypsum products (ISO 6873:1983)
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Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Dentistry - Dental gypsum products (ISO 6873:1983)Zahnheilkunde - Dentalgipse (ISO 6873:1983)Art dentaire - Produits dentaires a base de gypse (ISO 6873:1983)Dentistry - Dental gypsum products (ISO 6873:1983)11.060.10Dental materialsICS:Ta slovenski standard je istoveten z:EN 26873:1991SIST EN 26873:2000en01-januar-2000SIST EN 26873:2000SLOVENSKI
STANDARD
SIST EN 26873:2000
SIST EN 26873:2000
SIST EN 26873:2000
w - B O Y2 International Standard 6873 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION*ME~YHAPOllHAR OPTAHMJAUMR Il0 CTAHllAPTM3AUMM.ORGANlSATlON INTERNATIONALE DE NORMALISATION Dental gypsum products Produits dentaires à base de gypse First edition - 1983-11-01 UDC 615.463 : 616.314 Ref. No. IS0 6873-1983 (E) Descriptors : dentist!y, dental materials, gypsum, gypsum plaster, materials specifications. Price based on 8 pages SIST EN 26873:2000
Foreword IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies (IS0 member bodies). The work of developing International Standards is carried out through IS0 technical committees. Every member body interested in a subject for which a technical committee has been authorized 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. Draft international Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the IS0 Council. International Standard IS0 6873 was developed by Technical Committee ISO/TC 106, Dentistry, and was circulated to the member bodies in March 1982. It has been approved by the member bodies of the following countries : Austria India Sweden Belgium Japan Switzerland Canada Mexico United Kingdom China Netherlands USA Czechoslovakia New Zealand USSR Egypt, Arab Rep. of Norway Germany, F.R. South Africa, Rep. of The member bodies of the following countries expressed disapproval of the document on technical grounds : Australia France O International Organization for Standardization, 1983 0 Printed in Switzerland SIST EN 26873:2000
INTERNATIONAL STANDARD IS0 6873-1983 (E) Dental gypsum products O Introduction a This International Standard aims to enable users of dental gyp- sum products to obtain materials that are efficacious. The re- quirements have been designed to delineate satisfactory materials and rule out unsatisfactory ones. It is expected that both the manufacturer and user can use this International Stan- dard as a basis for producing or obtaining satisfactory products and results. 1 Scope and field of application This International Standard gives a classification of, and specifies requirements for, gypsum products used for dental purposes such as for making oral impressions, models, casts or dies. It also specifies the test methods to be employed to deter- mine compliance with these requirements. 2 Reference IS0 1302, Technical drawings - Method of indicating surface I) texture on drawings. 3 Definition testing consistency : That consistency obtained with a water/powder ratio by mass which gives a slump pat diameter or cone penetration meeting the property requirements given in the table. 4 Classification The four types of gypsum products used in dentistry and specified in this International Standard shall be classified as follows : Type 1 : Impression plaster Type 2 : Plaster Type 3 : Stone Type 4 : Stone, high strength 5 Requirements 5.1 Composition The material shall be composed essentially of finely powdered hemihydrate of calcium sulphate and necessary modifiers. 5.2 Flavour The material shall not be flavoured unless stated otherwise on the container. 5.3 Properties The material shall be uniform and free from foreign matter and lumps and when mixed according to the manufacturers instruc- tions shall produce a homogenous mix. NOTE - Colouring matter as such is not regarded as foreign matter. The material shall comply with the requirements for testing consistency, pouring time, setting time, setting expansion and compressive strength as specified in the table. In addition to being within the limits listed in the table, pouring and setting times shall also be within f 20 % of the times stated by the ’ manufacturer. Pouring and setting times shall be measured from the moment of initial contact of the powder with water. 5.4 Fracture (Type 1) When broken in accordance with 7.6 two minutes after the set- ting time (7.41, type 1 impression plaster shall break with a clean fracture and be readily reassembled to form the shape and size of the original unbroken specimen. 5.5 Reproduction of detail The material shall be capable of reproducing a continuous 0,02 mm step for the full diameter of the mould in at least two of three specimens prepared as described in 7.8. 1 SIST EN 26873:2000
IS0 6873-1983 (E) 6 Sampling, test conditions and preparation of test specimens 6.1 Sampling Sufficient standard packages of the material shall be obtained to provide at least 5 kg of sample. The sample shall be stored in a moisture proof container for subsequent testing. 6.2 Test conditions The preparation of test specimens and the test procedures shall be conducted at 23 f 2 OC and a relative humidity of 50 f 5 %. The testing equipment and sample container shall be conditioned at this temperature and relative humidity for at least 10 h prior to the test being carried out. The distilled water and sodium citrate solution (7.2.1) shall be maintained at 23 k 2 OC. 6.3 Mixing 6.3.1 Apparatus 6.3.1.1 bowl of about 130 mm diameter at the top. Clean, scratch free tapered rubber or plastic 6.3.1.2 Spatula, having a stiff, round-edged blade 19 to 25 mm wide and 90 to 130 mm long. 6.3.2 Procedure Mix the dry powder with sufficient distilled water in the follow- ing manner to produce a mix of testing consistency. Pour the water into the mixing bowl (6.3.1.1). Begin timing from the moment at which powder and water first make con- tact. Add the dry powder to the water over a period of 10 s. Allow the mix to soak for 20 s. Spatulate the mix for 3 type 2, 3 and 4 material tion at a rate of approxima Transfer the mix immediately to the moulds or testing ap- paratus. erials and for 60 s for a circular stirring mo- 7 Test methods 7.1 Inspection Determine compliance with the requirements given in 5.1, 5.4 and 5.5 by visual inspection (without magnification unless otherwise stated). 7.2 Testing consistency 7.2.1 Material Gauging liquid composed of 0,3 YO solution of sodium citrate in distilled water. NOTE - Only use the 0,3 % sodium citrate solution for the determina- tion of testing consistency. Use distilled water in the preparation of all specimens for determining other properties. Take care to avoid con- tamination of testing equipment with the sodium citrate solution. Use separate mixing equipment, if possible. 7.2.2 Types 1 and 2 Determine the testing consistency of type 1 impression plaster and type 2 plaster by a slump method using the following ap- paratus and procedure. 7.2.2.1 Apparatus 7.2.2.1.1 Clean, dry, cylindrical mould, having a length of 50,O mm and an inside diameter of 35,O mm constructed from a corrosion resistant, non-absorbent material. O 7.2.2.1.2 Clean, dry, smooth glass plate, with sides of at least 100 mm. 7.2.2.1.3 Means of measuring the major and minor diameters of the slumped mix. 7.2.2.2 Procedure Add 100 g of the sample to the test quantity of the gauging liquid and mix as described in 6.3. Place the mould (7.2.2.1.1) upright on the centre of the glass plate (7.2.2.1.2). Completely fill the mould and level off the mix flush with the top of the mould. Rest the plate on a surface that is free of vibration. After 2 min from the start of mixing, lift the mould vertically from the plate at a rate of approximately 10 mm/s and allow the mix to slump or spread over the plate. After 3 min from the start of mixing, determine the major and minor diameters of nearest millimetre. Take the average df$x es) as a measure of consistency. If the requirement given in the table, repeat the test with more or less gauging liquid un- til the required testing consistency is obtained. 7.2.3 Types 3 and 4 Determine the testing consistency for types 3 and 4 stones by a cone penetration method using the following apparatus and procedure. ' e 7.2.3.1 Apparatus Cone penetrometer, an example of which is shown in figure 1. Use a rod and plunger (B and G) and additional weight (A) such that the total mass is 100 f 0,l g. 7.2.3.2 Procedure Clean the plunger, mould, and base plate (figure 1) and apply a thin coat of lubricant to the upper surface of the base plate in order to prevent leaks during the test. NOTE - Petroleum jelly is a suitable lubricant. 2 SIST EN 26873:2000
IS0 6873-1983 (E) Add 300 g of the sample to the test quantity of the gauging liquid and mix as described in 6.3. Pour the mix into the conical ring mould (large end uppermost) and work the mix slightly to remove air bubbles. Commence penetration and record results at 3 min, 4 min and 5 min after the start of the mixing as follows : Level the mix flush with the top of the ring mould before each penetration. Wipe the conical plunger clean with a damp cloth, then lo
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