ISO 11609:2010 pdf free download – Dentistry一Dentifrices 一Requirements, test methods and marking.
A.3.3.2.2 Preparation
The entire labial surface of the specimen is used after removing the root. Clean the enamel in the same way
as the root.
A.3.3.2.3 Irradiation
Irradiation of the enamel is identical to the method used with the roots. The roots and enamel specimens may be packed together for submission to the reactor.
A.3.3.2.4 Mounting
Mount the enamel specimens in the same way as the roots. The labial surface shall protrude 2 mm and be
parallel to the resin surface.
A.3.4 Toothbrushes
The toothbrushes5) used should have nylon filaments about 10 mm in length. Filament ends should lie in a plane.
Store the brushes in water overnight prior to their first use and then keep them in water until they are discarded. Use a new set of brushes for each set of teeth. Do not remove the brushes from the machine between runs but raise the tufts off the specimen so as not to bend the bristles. At the beginning of each run, set the tension of the brush on the specimen to 150 g using a Chatillon spring gauge or equivalent. This tension should be rechecked at least twice daily. The method of adjusting the tension will vary depending upon the type of mechanism on the brushing machine.
A.3.5 Reference diluent
The diluent is a 0,5 % carboxymethylcellulose (7MF CMC)6) solution in 10 % glycerine. To prepare 11 of the diluent, heat 50 ml of glycerine to 60 °C and add 5 g of CMC while stirring. When the mixture is homogeneous, add another 50 ml of heated glycerine and continue stirring for 60 mm. Transfer the solution to a 11 flask and add 900 ml of distilled water. Allow to cool but continue stirring slowly overnight. To stabilize the viscosity, allow the solution to stand overnight before using. This solution is used to make up slurries of the reference abrasive or any powder being tested.
A.3.6 Reference abrasive slurry
Using the reference material described in A.3.1, dilute 10 g of the abrasive with 50 ml of the diluent (A.3.5). The same ratio is used for all powders. It is possible for the reference abrasive to be used as a dentifrice. If this is the case, it shall be made up as a 40 % abrasive dentifrice with the rest of the constituents being conventional dentifrice components. The slurry is then made using 25 g of reference dentifrice and 40 ml of water.
A.3.7 Dentifrice slurries
To prepare the test slurries, add 40 ml of water to 25 g of each dentifrice. For the machine, prepare eight slurries of each dentifrice. This dilution produces a final slurry volume and concentration similar to those of the reference abrasive slurry. All slurries (reference and test) should be used shortly after preparation and after vigorous mechanical stirring to prevent particles from settling.
A.3.8 Preconditioning of tooth specimens
A.3.8..1 Dentine
To reduce the variation caused by dentine surface differences, precondition the specimens prior to each use. The preconditioning treatment consists of brushing with a slurry of the reference abrasive but not taking a sample. The first time dentine specimens are used, the preconditioning should be for 6 000 strokes. Each successive daily run should begin with a shorter preconditioning brushing of 1 000 strokes. The tension of the toothbrush on the roots shall be 150 g.
Discard the preconditioning slurries.
A.3.8.2 Enamel
Preconditioning of the enamel is similar to that of the dentine, except that 10 000 strokes are used prior to the first use and 1 000 strokes are given at the beginning of each day.
Discard the preconditioning slurries.