Onlay method - technician prepares special dental onlays, based on an impression, then a whitening gel is applied into them. Depending on its concentration, the patent wears them from one to four hours. Teeth should be carefully cleaned before the procedure and after it, the patent should not eat anything for a couple of hours. The whitening process should be repeated for at least nine evenings. The modern preparations which I recommend eg. NiteWhite contain a formula minimizing pain discomforts during such treatment. The whitening effect is long-lasting and less traumatic than single session brightening. Furthermore, the onlays can be also used for application of other medicines (fluorization, Tooth Mousse, oversensivity reducing formulas) as well as repeated whitening when the effect of brightening becomes to decline. In such case it’s enough to repeat the procedure for three nights in a row.