Glorysmile V34 Colour Corrector utilises colour correcting technology. Purple is directly opposite yellow on the colour wheel and is therefore its complementary colour, so a water-soluble purple dye is applied to your teeth to cancel out any yellow undertones.GlorySmile V34 is a non-invasive brightening treatment. Simply apply the v34 Colour Corrector to your toothbrush like a regular toothpaste, and brush! V34's Colour Corrector's combination of two water-soluble dyes allow for any shade of yellow to be cancelled for the brightest smile, without leaving behind any residue.