A University of Michigan review of 25 studies concludes at-home tooth-whitening products are effective in the short term.
University of Michigan School of Dentistry researchers said most of the studies followed patients for only two to three weeks, so there was not enough data to reach a conclusion on long-term results, WebMD reported Wednesday.
The review found that users of tooth-whitening gels and strips did experience a whitening of their teeth, while those given placebo products recorded no change.
The reviewers said mild to moderate tooth sensitivity and gum irritation were common side effects of the products, especially those containing large amounts of hydrogen peroxide.
However, they warned, the lack of long-term data could obscure possible long-term risks.
"Given the lack of information on long-term benefits and harms, there may be a huge void between the state of knowledge based on the trials sponsored by the manufacturers and the experiences of millions of users of tooth whitening products," they wrote.
"Over-the-counter or dentist-dispensed tooth-whitening products can be recommended to the public but with strong cautions," the review concluded.
Copyright 2006 by United Press International