Stains related to the dental structure are generally grouped into extrinsic or intrinsic. The frequent or repeated use of tetracycline and the imperfections of tooth development as well as other factors such as fluorosis are what causes intrinsic stains. Other localized stains, for example in the pellicle, are usually extrinsic blots which are generated by amino acids and sugar reactions or often caused by exogenous chromophore residues in the pellicle. The most recent trends of teeth-whitening techniques applied in such cases employ the use of clinical measures. There are professional products meant for tooth-whitening usage found in most dental health care clinics. Some of these products can also be accessed over the counter from various pharmaceuticals and/or chemists. These products employ the use of anticalculus agents, abrasives, low hydrogen peroxide, and surfactants. The products are mixed for the professional treatment.
The most recent trends of teeth-whitening have also seen the development of various products and chemical mixtures that allow individuals to maintain good dental structure without having to go see a dentist. Dentists have even approved various dental kits that can be easily used at home.