Ionic System

These teeth whitening systems use ionic technology to remove surface stains caused by food, wine, coffee, and smoking. After applying a hydrogen peroxide-based gel to your teeth, you'll use a double-bite mouthpiece for five minutes. "Once the unit is switched on, a mild micro-current transfers to the whitening gel formula," Smigel says. "The hydrogen peroxide in the gel transforms to oxygen to break down stains on the teeth. The ionic technology reduces tartar buildup and kills bacteria that cause bad breath."

If patience isn't among your virtues, an ionic system might be right for you. "The unique design of the tray allows whitening of the front, back, top and bottom of all teeth at the same time," Smigel says. "A few shades' difference can be immediately seen after each treatment, so it's perfect for people who don't have a lot of time to devote to enhancing their smiles."

But, if you're dreaming of an eternal gleaming smile, you may need to adjust your expectations. Because the formula's hydrogen peroxide dehydrates teeth, they may become more sensitive, and whitening results can be temporary. "Once the teeth rehydrate, often in one week, the whiteness will subside," Smigel says. "Touch-up treatments every three months are recommended." He notes that if you have a dental restoration or sensitive chompers, it's best to pass on this method.

Tanda Pearl Ionic Teeth Whitening Kit, $195, available at Ulta.