Yellow teeth will not necessarily be scaled white, but will be discerned mainly according to the cause of yellow teeth. If the yellow teeth are caused by serious plaque and stains on the surface of the teeth, scaling can completely clean the plaque, calculus and stains and restore the original color of the teeth, which will make the teeth white at this time. If the yellowing is caused by the teeth themselves, scaling will only clean the teeth completely and will not change the color of the teeth themselves. You can whiten your teeth through cold light whitening treatment, which can be done in forty-five minutes, and the whitening can be improved by about two shades, but the effect can only be maintained for about three years, and the teeth will return to their original color after three years.