ISO 9693:2019 pdf download – Dentistry – – Compatibility testing for metal-ceramic and ceramic-ceramic systems .
4.2.4 Thermal shock resistance
At least one thermocycling test for resistance to thermal shock shall be performed according to 6.5.3 or 6.5.4 and the results be reported according to Clause Z.
5 Sampling
5.1 Metallic substructure material
The sample shall be adequate for preparing the test specimens in accordance with this document. All of the metallic material shall be from the same lot and uinused.
5.2 Ceramic substructure material
The sample shall be adequate to prepare the specimens for testing in accordance with this document.
All of the ceramic material shall be from the same lot.
5.3 Veneering ceramic
The sample shall consist of a sufficient amount of veneering ceramic to carry out all tests in accordance with this document, including the tests performed according to ISO 6872. Perform the tests on the colour/shade variant most commonly used. All of the material tested shall be from the same lot.
6 Test methods
6.1 Linear thermal expansion
6.1.1 Metallic materials
Test methods for metallic materials shall be in accordance with IS0 22674:2016, 8.13.
6.1.2 Ceramic materials
Test methods for ceramic materials shall be in accordance with ISO 6872:2015, 7.4.
6.2 Glass transition temperature
The glass transtion temperature shall be determined in accordance with ISO 6872:2015, 7.5.
6.3 Young’s modulus
Test methods for elastic modulus of metlic materials shall be in accordance with ISO 22674:2016 5.5.
6.4 De-bonding/crack initiation test
6.4.1 Apparatus Flexural-strength testing machine for three point bending, having a span between supports of (20士0,1) mm and capable of a cross-head-speed of (1,5 + 0,5) mm/min. Supports and bending piston shall be rounded to a radius of (1,0土0,1] mm and shall be made from hardened steel or other hard material having a hardness greater than 40 HR (Rockell C-scale) and have a smooth surface with a roughness less than 0,5 um Ra.
6.5.2 Preparation of test specimen
Prepare, according to the instructions for use, either at least one veneered prosthesis of three units (bridgework, with the geometry of tooth positions 11 to 13 or 14 to 16) or, if multiple units are not indicated, at least five anterior crowns (geometry of tooth position 11 or 21). Apply the veneer to the substructure material with at least two lirings.
NOTE The numerical tooth designations are in accordance with ISO 3950.
6.5.3 Thermocycling test with fixed temperature Interval Apparatus ContaIner with cold water maintained at (10 ± 10) °C ContaIner with water maintained at its boiling point. WIre basket suitable For transferring the test specImen(s) rapidly between the containers, and preventing theni from coming in direct contact with the walls or bottom while ensuring that the test piece or pieces remain submerged. Procedure
a) Place test objects in the wire basket so that they are not contacting each other and are not under mechanical stress.
b) Place the basket in the boiling water for (30 ± 5) s. When executed for the first time this step is counted as the first thermal shock.
c) Transfer the basket from the boiling water to the cold water within 3 s and keep it submerged for (30 ± 5) s. When executed for the first time this step Is counted as the second thermal shock.
d) Repeat steps b) and c) at least eight times or until failure of the materials Is apparent. Transfer the test specimens between containers within 3 s.
e) After the last quenching, remove ohects and dry them.
f) Examine specimens according to Examination
Examine each specimen for cracks by light microscopy at magnifications up to 10 x with transillumination,
If cracking Is not observed Immediately after the test, repeat the examination after 48 Ii to test for delayed cracking. Test report
Prepare a test report in accordance with Clause 7.
6.5.4 Thermocycllng test with Increasing temperature interval Apparatus Container with cold water maintaIned at (10 ± 10) C by an external temperature control element.