Color molecules from foods and beverages accumulate on tooth surfaces, specifically, pellicle, and slowly penetrate the microstructure (enamel, dentin) of your teeth.
Extrinsic stains (within the pellicle layer) can be removed by brushing your teeth. The abrasive action of brushing removes bacteria and food debris that reflect color. Intrinsic stains — those within the the enamel and dentin — can be removed with oxidizing agents, such as peroxides (bleach) or sodium bicarbonate.
While peroxide-based whitening is generally accepted as safe, adverse effects can occur with inappropriate application and use.
According to the ADA, on rare occasions, irreversible tooth damage has been reported. The ADA thus cautions that “not enough information is available to support unsupervised long-term and/or repeated use of bleaching products.”
Most studies have shown little or no changes on bleached enamel surfaces. However, two clinical cases reported significant enamel damage with the use of over-the-counter products. Others have suggested that hydrogen peroxide alters the structural and biochemical properties of hard and soft dental tissues. The effect varies with peroxide concentration, duration, and frequency of peroxide use.
Temporary tooth sensitivity is the most common side effect (often affecting ~50% of folks in studies). In the bleaching process, hydrogen peroxide breaks down into water, oxygen, and free radicals. Molecules seep deep into your enamel and dentin, which contain nerve endings. Sensitivity is an indication of pulp irritation to all the stuff released in the bleaching process.
Temporary gum irritation is another common side effect. If whitening gels are not applied properly (too much gum contact), you’ll get chemical burns on your gums. Irritation usually subsides within a few weeks.
Sodium bicarbonate-based whitening products are a great alternative for those who are concerned about sensitivity. The active ingredient is household baking soda. Sodium bicarbonate is an oxidizing agent like hydrogen peroxide, but it’s much less aggressive. It’s gentler on the teeth and gums. The whitening process takes longer, but you don’t have to worry about gum or tooth irritation.
However, stains will naturally accumulate post-whitening as color molecules build up from food and drink consumption over time.
Whitening pens contain the same active ingredients as traditional whitening kits (tray and gel). Yes, they work! However, the process will take longer since your saliva flow will naturally wash away and break down the whitening agents.
After consuming dark foods or beverages:
1. Eat something to stimulate saliva flow. Saliva is the body’s natural “car wash” and will help wash away color molecules from the surface of your teeth. Foods that stimulate saliva flow include pears, apples, celery, and gum.
2. Floss and brush 30 minutes after eating. Get the color molecules off the surface of your teeth before they penetrate your tooth.
3. Drink lots of water after you eat. Wash away all that color before it seeps into your teeth.
4. Drink dark beverages (like iced coffee) through a straw.