All toothpastes can be considered whitening because they contain mild abrasives that help remove surface stains gradually. They are considered the most mild option, but they can usually only lighten teeth about one shade.
Rinses that contain whitening chemicals are a fairly new innovation. By swishing twice per day for 60 seconds, you can prevent gum disease, buildup of plaque, freshen your breath and whiten your teeth. Some experts say that 2 minutes per day can’t compare to the 30 minute-per-day exposure of whitening strips. However, one could argue that if you already use mouthwash in your general routine, it wouldn’t hurt to switch to a whitening rinse even though it may not lead to dramatic results.
Whitening strips are very thin and usually transparent plastic strips that are coated with a whitening gel. Whitening gels are peroxide-based and act as a bleaching agent for your teeth. People are instructed to apply the strips once per day for 30 minutes for 14 days. These can be effective in lightening your teeth a couple shades, and results can usually be maintained for three to four months.
Most over-the-counter methods will show limited results overall because of the nature of over-the-counter drugs. Typically, very strong and more effective chemicals will need to be applied in-office by a dentist.