US Patent 10099064 Tooth-whitening process

A tooth-whitening process includes providing an array of LEDs disposed in a first plane and forming an inner arc having an inner focal point and an outer arc having an outer focal different from the inner focal point; applying a whitening composition to at least the anterior surfaces of at least six mandibular or maxillary anterior teeth and maintaining the whitening composition on the at least six teeth for a first time period; after the first time period, directing a light radiation comprising blue visible light or near-visible UV light of at least a threshold intensity from the least a first array of LEDs for a second time period to the anterior surfaces of the at least six teeth, the first time period having a duration greater than 50% of a total duration of the first time period and the second time period; and removing the whitening composition from the at least six teeth.