ISO 12836 pdf download – Dentistry -Digitizing devices forCAD/CAM systems for indirect dental restorations -Test methods for assessing accuracy

ISO 12836 pdf download – Dentistry -Digitizing devices forCAD/CAM systems for indirect dental restorations -Test methods for assessing accuracy.
3.9
random error
result ola measurement minus the mean that would result Ironi an inlinite number of measurements of the same measurand carried out under repealable conditions
Note Ito entry: Random error is equal to trueness minus systematic error.
Note 2 to entry: In practice, random error may be estimated from 20 or more repeated measurements of a measurand under specified conditions.
3.10
relative error
trueness divided by a true value of the measurand
3.11
repeatability
(results of measurements) closeness of the agreement between the results of successive measurements of the same measurand carried out under the same conditions of measurement
Notc 1 to entry: Repeatability Ls a qualitative concept. Its quantitative counterpart is standard deviation of repeatability or coefficient of variation of repeatability of the measurement resu Its.
Note 210 entry: Repeatability may depend on the value of the measurand.
3.12
repeatability conditions
conditions where independent results of measurements are obtained with the same measurement procedure in the same laboratory by the same operator using the same equipment within short intervals of time without new calibration
[SOURCE: ISO 5725-1:1994, 3.14, modiliedl
3.13
reproducibility
results of measurements
closeness of the agreement between the results of measurements of the same measurand carried out under changed conditions of measurement
Note Ito entry: The changed conditions may include principleoimeasurement, method of measurement, observer, measuring instrument, reference standard, location, conditions of use, and time.
Note 2 to entry: The set of specified conditions is termed reproduclbility conditions”.
Note 3 to entry: Reproducibility is a qualitative concept. Its quantitative counterpart is standard deviation of reproducibility or coefficient of variation of reproducibility of the measurentent results.
Note 4 to entry: Reproducibility may depend on the value of the measurand.
3.14
reproducibility conditions
conditions where results of measurements are obtained on the same measurand under different conditions in different laboratories
Note ito entry: the differences in conditions arc intended to be specified.
A.1 General
This annex specifies the measurement of a die which simulates an Inlay-cavity. This test procedure uses a negative geometry.
A.2 Principle
An inlay-cavity die is lit-st measured with a reference measurement system in order to produce a reference data set (calibration of the measurement obect).
Then, the digitizing device under investigation is used to capture the inlay-shaped physical object. The resulting measurement data are compared to the reference data set.
A.3 Apparatus
A.3.l Test specimen, in the form olan Inlay-shaped physical obfrct. as specified in Figure ii. The material of the physical object shall be a dimensionally stable material. It shall be resistant to handling wear. It shall be compatible with spray wheti Indicated as neessary for the use of the digitizing device.
NOTE The selection ola material which fulkis the condition of being a dimensional stable material depends on the digitizing device.
A.3.2 Reference measurement system, with an accuracy of ±2 pm.
A3.3 TravellIng microscope, with at least 20 magnification, accurate to 0.01 mm.
A.3.4 Digitizing device under investigation.
A.4 Preparation of test specimen
A4.1 Geometr3 dimensions, and tolerances
Figure A.1 gives three primary views of the Inlay-cavity die.
The precisely machined die shall be produced with a defined edge radius.
The specimen consists of the die itself and a computer-aided design model. lither the die itself is produced with a manufacturing accuracy of ±2 am or the die Is measured with a measuring device with an accuracy of ±2 pm.