There is a possibility that DIY kits will include chlorine dioxide. Both drinking water and swimming pools employ chlorine dioxide, the same ingredient. It removes tough stains, but at the cost of enamel erosion and dentin exposure. In the absence of enamel, teeth are susceptible to decay and infection.

When using an at-home whitening kit, the user is often required to wear a mouthguard that includes the whitening ingredients. These products state that a certain period of time with the guard in the mouth is necessary for optimal outcomes. Because the kits include high concentrations of hydrogen peroxide, there is a potential for chemical burns in the event of a spill. This is why a do-it-yourself kit may not always be the ideal choice when it comes to whitening your teeth.