Saving $100 on this sonic electric toothbrush will make you smile

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If you've been thinking about making the swap from a manual brush to a sonic electric toothbrush, the science is on your side. Manual toothbrushes aren't bad, but they're not ideal. Studies show that you're more likely to get a brighter, healthier smile when you use an electric toothbrush.

Need a little more motivation? How does $99 off a top-rated electric toothbrush sound? The popular AquaSonic Black Series Toothbrush & Travel Case with 8 Dupont Brush Heads is on sale right now for just $40 — it's usually $139. At over 70 percent off, this is one of the best sonic toothbrush deals we've found!

$40 $139 at Yahoo Life Shop

Why the AquaSonic Black Series toothbrush?

The AquaSonic comes with all the advantages of a sonic electric toothbrush (more on that in a minute!) with some extra perks that make it more than worth it. Users of the AquaSonic benefit from:

• A 40,000 VPM motor. This intense motor whisks away 10 times more plaque than a traditional toothbrush, dissolving stains and whitening at the same time.

• Four customizable modes. Brush the way you want with the option to swap between soft, whiten, massage and cleaning modes.

• Eight brush heads included. With the American Dental Association (ADA) recommending that people replace their toothbrushes every three to four months, buyers of this bundle have at least two years' of brush heads stocked up, which amounts to big savings.

Check out this video to see the AquaSonic in action.

Which should you get: a sonic electric or manual toothbrush?

Electric toothbrush devotees believe they get a better clean, while manual toothbrush users think that with enough elbow grease, they'll get the same results at a fraction of the price.

So who's right?

Both electric toothbrushes and manual toothbrushes can help keep your teeth and gums healthy, but there are a few features that edge electric toothbrushes ahead in studies. Here are some pros and cons of both:

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Electric toothbrushes:

• Motorized/vibrating bristles for better plaque reduction

• Cleaning modes to customize experience

• Built-in timer to help you meet ADA standards

• Higher cost

• Requires regular brush head replacement

Manual toothbrushes:

• Fixed bristles

• Depends on operator's speed and pressure

• May wear out sooner or cause bleeding due to excessive pressure

• May be more tiring so users may quit use faster

• Inexpensive

In the end, scientific results don't lie. Over an 11 year study, researchers documented that those using electric toothbrushes had less decay and healthier gums — and they did not lose their teeth as quickly as manual toothbrush users. Seems like not losing your teeth is something we can all agree is a major plus in the electric toothbrush column.

This is a deal you don't want to miss out on. Smile wider — and whiter — with your new AquaSonic Black Series Toothbrush for just $40.

$40 $139 at Yahoo Life Shop