But they can cause discomfort and will not get the job done as well. Some OTC kits come with a bendable mouthpiece. These work much better than a person-dimension-matches-all trays. The bleaching gels that are available in these kits aren’t as strong as the ones you receive from the pro. https://teethwhitening30517.boyblogguide.com/26275816/everything-about-teeth-whitening-sa