There are 2 main differences between most in-office whitening procedures versus Crest Whitestrips. One, how the whitening ingredient is applied and two cost. Both whitening methods use the same whitening ingredient: hydrogen peroxide. However, Intensive Professional Effects Whitestrips use a 10% concentration, while most in-office procedures use up to a 35% concentration. Lights and lasers are also used during in-office procedures to help show results more quickly than at-home procedures. However, because of this immediacy in results, in-office treatments cost more than Whitestrips. So, if speed is a priority for you, but cost is an issue, then try Intensive Professional Effects Whitestrips. They deliver professional-level results in the convenience of your home