How it works: Over-the-counter whitening strips use low levels of hydrogen peroxide to bleach your front teeth over a matter of weeks. The products are affordable, effective and widely available.

The only downside to whitening strips is that they can take many uses to work. "Saliva de-activates the active whitening ingredient," Deutch says. Since whitestrips sit exposed in your mouth, they don't stay effective for very long. "Depending on how often you use them, you might have to wait a month to get the results you want," he says. Luckily, dentists agree that with consistency, the products offer impressive results.

What to use: Deutch and Stirneman sing the praises of Crest 3D White Whitestrips, $27.99. "They have many different varieties for patients' needs," says Deutch. For example, the Gentle Routine kit suits sensitive teeth and gums, while the One-Hour Express kit offers faster results at a slightly higher price.

When you'll see results: 12 days to 1 month (when used daily for 30 minutes)

How it works: While whitening strips don't provide any kind of barrier between your saliva and the active ingredient, over-the-counter whitening trays do. "For that reason, you might see results quicker," says Deutch. "As long as you stick with it."

With over-the-counter whitening kits like this, you receive a pre-made tray, which you fill with hydrogen peroxide gel and fit around your top teeth like a mouth guard. The tray surrounds your teeth, unlike strips, which simply sit on top. The tray is not custom, so it might not fit perfectly in your mouth or feel as comfortable as the strips, but you will likely see more immediate results.

What to use: We recommend the Plus White 5 Minute Speed Whitening System, $10.90, available at drugstores. Squeeze the included whitening gel into the tray, place it in your mouth and wait for five to 20 minutes.

When you'll see results: 1-2 weeks (when used twice daily)

How it works: Pro whitening trays that you'd get from a dentist offer a custom fit, based on a mold taken in-office, as well as higher concentration whitening gel. The trays are clear and fit perfectly to your teeth, so they tend to be more comfortable than the clunky over-the-counter option (meaning you might be more motivated to stick with them). However, if you're severely dentist-phobic, but still want pro-grade results, there's a way to create a custom set of clear trays at home.

What to use: Smile Brilliant's Teeth Whitening Trays, $119.95, work just like those you'd receive from a dentist. In the mail, they send you the materials to create a custom mold of your teeth -- send it back, and within a week you'll receive your trays, along with syringes filled with a 22 percent carbamide peroxide gel, which is significantly more concentrated and effective than most at-home products. (You can choose to receive 3, 6 or 9 syringes, each of which lasts for 3-4 full applications). Wear the trays on top and bottom teeth for a couple hours per day, and you'll find dramatic results within a week or two. It's the closest you'll get to an in-office treatment without having to spend 600 bucks and an afternoon at the dentist's.

When you'll see results: 4-14 days (when used for 1-3 hours, daily)

How it works: Bleaching treatments at the dentist's office often involve directing a blue LED light at the peroxide gel on your teeth. The light and heat help to lock in the peroxide's whitening oxygens, making them react more quickly, explains Deutch. Professional grade at-home blue light devices have a similar effect. The faster process means less exposure to the gel, making these treatments better suited to sensitive teeth.

What to use: Deutch recommends the Glo Science Glo Brilliant Personal Teeth Whitening Device, $220, which comes with whitening gel that you apply directly onto teeth and a rechargeable light-up mouthpiece that goes over the gel. (A sensitive mouth solution is also included, which you can apply to your lips and gums beforehand). The light-up mouthpiece plugs into a charger that hangs around your neck, as it sits in your mouth for four consecutive eight-minute sessions. Yes, it looks a bit like a futuristic torture device, but used daily, the results are standout.

(If your teeth are ultra-sensitive, Gulizio recommends also prepping for your whitening treatment with an over-the counter teeth desensitizer, such as Dentist On Call SenzAway Tooth Desensitizer Gel, $4.29).

When you'll see results: 5-10 days (when used 32 minutes daily)

How it works: If you're opposed to chemical-infused bleaching treatments and toothpastes, but still want whiter teeth, you might opt for a DIY remedy. "Ingredients with highly acidic content can remove stubborn surface stains, possibly even faster than whitening toothpastes," says Stirneman.

What to use: To create your own at-home whitening solution, Stirneman recommends diluting some apple cider vinegar with water and mixing with an all-natural toothpaste (such as Tom's of Maine Simply White Toothpaste, $4.99). Mix three parts water and one part vinegar with your toothpaste, brush and rinse very well, so none of the acid remains on your teeth.

When you'll see results: Within 3 months