Dental chromogens

Dental chromogens are chemical compounds responsible for the discoloration of teeth, categorized into extrinsic and intrinsic types based on their origin and location within the dental tissue (Watts & Addy, 2001). Extrinsic chromogens are typically derived from exogenous sources such as tannins in tea, polyphenols in red wine, and tobacco products, which adhere to the acquired pellicle on the enamel surface (Nathoo, 1997). Intrinsic chromogens, conversely, are integrated into the tooth structure itself, often resulting from metabolic products like bilirubin, systemic medications like tetracycline, or excessive fluoride intake during odontogenesis (Joiner, 2006). These molecules often contain conjugated double bonds or chromophores that absorb specific wavelengths of light, resulting in visible staining. In clinical practice, these substances are the focus of tooth whitening procedures where oxidizing agents, such as hydrogen peroxide, are applied to chemically degrade the chromogenic structures (StatPearls, 2023). The oxidation process breaks down the complex organic molecules into smaller, colorless components, thereby restoring or enhancing the aesthetic appearance of the dentition.

Other names

Tooth stainsExtrinsic dental stainsIntrinsic dental stainsDental pigmentsChromophores

Oxidative degradation of chromophore double bonds to reduce optical density and pigment visibility.