Laboratory Evaluation of Dental Floss


The primary objective of this study was to determine the stain removing ability of STAINO® dental floss.

The secondary objective was to evaluate the effect of the STAINO® dental floss on natural tooth enamel (safety evaluation).


Stain Removal

The Minolta Colorometer measurements show a significant decrease in the amount of stain on the test bovine tooth enamel surfaces when brushed for 10,000 reciprocal strokes. The amount of stain removal was dependent on the level of initial stain: lighter stains were removed more significantly and sooner than heavier stains.


Examination of human enamel under the SEM (Scanning Electron Microscope) at 1000X magnification shows no adverse changes in surface condition (i.e., no scratches) after 10,000 brush strokes. The brushes do not abrade human tooth enamel to any measurable extent.

1. Microscopy of the Floss

SEM Photomicrographs of the floss are shown in SEM 1 and SEM 2. The abrasive particles can be clearly seen at high magnification.

SEM 1 - STAINO Dental Floss 25x SEM 2STAINO Dental Floss 1000x
2. Stain Removal

The data of the Minolta Colorometer for the average of all samples tested are shown in the table below. There was a significant progressive lightening of the tooth as compared to the baseline (unflossed) state as shown by the increase in the E values.

# of Reciprocal 
Flossing Strokes
20 10.34
50 17.17
100 23.76
200 30.76

The digital images of the sequence of flossing stain removal for a representative sample are shown in SEM 3 and SEM 4.

3. Safety

No adverse effect of the floss on natural tooth enamel was determined using the SEM at 25 and 100x. No scratches were seen on the enamel surfaces after 200 reciprocal strokes. The results of a representative sample are shown in Colorometer 1 and Colorometer 2.