Age-Related Darkening Treatments
The second major cause of teeth discoloration is age-related darkening. The color layer of the teeth is the dentin, about two millimeters underneath the enamel. The color of the dentin is largely genetically determined and unaffected by what we eat, drink or smoke.
We see the dentin’s color through the “frosted glass window” of the colorless enamel. As we age, the color of the dentin slowly deepens and darkens, resulting in darker teeth, even when free of surface stain.
Treatments for age-related darkening include over-the-counter home bleaching kits and trays and professional in-office whitening treatments.
All these systems are somewhat similar, in that they use a bleaching gel, placed in contact with the teeth for a period of time, that penetrates through the enamel and lightens the colored dentin layer of the teeth.
The effectiveness and permanence of these systems largely depends on the formulation of the bleaching gel, its strength, how it’s activated and the length of time it’s in contact with the teeth.
Over-the-counter at-home systems use a relatively diluted version of bleaching gel, usually applied in a generic tray or adhesive strip. These systems can have some moderate, short-term success, but results vary greatly, depending on how well the user is able to apply the bleaching agent and keep it in place for the hours and days required.
The at-home bleaching gels are diluted to protect the user from damaging the gums, cheeks and lips, but this decreases its effectiveness and permanence. The increased time necessary for at-home systems usually leads to temporary teeth sensitivity to temperature, usually for several days.