Video: What is the best way to whiten teeth?

In the age of selfies, it seems everyone wants to have a whiter, brighter smile. While one option to achieve this involves a trip to the dentist for a professional whitening, many people have turned to over-the-counter teeth-whitening treatments.

How do these work, and are they safe?

This week, Reactions looks at the chemistry of a whiter smile.

Check it out here: