Go Smile: Smile Whitening System

Bottom line

Go Smile: Smile Whitening System may not whiten teeth as dramatically as Crest 3D White Whitestrips Advanced Vivid (*Est. $40), but it is easy to use, can be used anywhere and is less likely to cause sensitivity. It isn't reviewed as often as Go Smile: B1 Whitening System (*Est. $50), which is also very gentle and convenient to use. Both systems are best for those who only need minimal whitening.

Performance

Slightly whiter teeth. Go Smile: Smile Whitening System is an ampoule-encased, brush-on formula much like Go Smile: B1 Whitening System (*Est. $50). This new system has a higher level of whitening ingredients and a more viscous gel for faster results -- meaning you only need to use it for seven days instead of 10. The system is best suited for touching up or maintaining teeth that are already white.

Manufacturers of Go Smile: Smile Whitening System say the formula can lighten teeth by up to six shades. Reviewers have mixed opinions, however. We only found a handful of user reviews at Amazon.com, and they are split down the middle as to the efficacy of the formula. One reviewer says, "I am shocked at how well this stuff works ... I look like I should be in a tooth paste commercial." Another says, "I used as directed for 7 days. No difference, no result." We didn't find any professional reviews that comment on Go Smile's performance. The great difference in the results of users could be caused by varying conditions of reviewers' teeth as well as varying degrees of expectation.

Ease of use

No rinsing required. Like Go Smile: B1 Whitening System, the Smile Whitening System gets rave reviews for its ease of use. It earns a Best Beauty award from InStyle magazine for dissolving quickly without the need for rinsing and because it allows users to "whiten on the go." The ampoules can be stowed in a purse or suitcase for easy portability, and it takes less than two minutes to apply the formula. In order to keep the gel in place, users must refrain from eating or drinking for 20 minutes.

Safety

Gentle whitening. Research shows teeth-whitening treatments to be safe but the ADA advises discussing treatment with your dentist before beginning any whitening program. That's because bleaching formulas can further aggravate and damage cavities, exposed roots and gum disease.

Go Smile doesn't publish the percentage of active ingredients in its Smile Whitening System, so it's hard to know how strong the formula is. Reviewers, however, say the whitener is very gentle. Testers at Real Simple magazine give the formula a zero on the sensitivity scale. Reviewers at Amazon.com agree -- most say that it causes no sensitivity whatsoever.