It's not created as a cure. Bright dental is a daily routine, just like human toothbrushing, and the regular use of the toothpaste + dental chew combo is a good way to stay on top of the stuff that causes problems.
Every dog is different, but if your dog has bad breath caused by debris and surface plaque, you should notice a big difference after getting your dog into the habit of using Bright dental.
If your dog's bad breath is caused by tooth decay, gingivitis, or worse, Bright dental is not going to "cure" anything. Talk to your vet and follow their recommendations, and then consider Bright dental after whatever course of treatment they recommend. As a human, toothbrushing doesn't cure cavities; you still go to the dentist first and floss later.
