The tooth is made up of enamel, dentin and dental pulp.
Each of these components has the ability to scatter and reflect light in a different way.
Because of these optical properties, but also because tooth structure changes with age, teeth can become yellower over time.
Dyschromia is a term that refers to the discoloration of a tooth or a limited number of dental units.
This results in differences between the shades of two adjacent teeth, an unsightly situation that can have a great psychological impact on the patient.
Tooth color is defined by 3 parameters:
shade: this gives the basic shade or wavelength of the color
saturation: represents the amount of pigment in a given shade
brightness: the property of allowing light to pass through the tooth structure.
There are two types of discoloration: external, when only the enamel is affected and it is due to external factors such as substances and chromogenic foods ingested by the patient, or internal, which affects the deeper layers and is caused by processes occurring in the dentine and pulp.
Extrinsic dyschromia
As mentioned above, this type of dyschromia involves the outer layer of dental hard substance, i.e., enamel, and can be caused by ingestion of chromogenic drugs or foods.
The treatment protocol for extrinsic discoloration includes professional scaling and brushing by the dentist using more abrasive toothpastes.
It is good to know that if the patient does not remove from the diet the factors that led to the pigmentation of the teeth, they will reappear after a short time.
Chromogenic factors
Tartar: responsible for generating yellowish discoloration
Chlorhexidine mouthwash: after prolonged use of chlorhexidine mouthwash, studies indicate the appearance of brown pigmentation spots
Tobacco: stains ranging from yellow to brown
Teas, coffees, colored juices
Internal dyschromia
Affect internal dental structures or can be caused by substances used in root canal treatments, dead dental pulp or abnormalities in the structure of component tissues.
Chromogenic factors
Tetracycline: given during pregnancy, it affects the dental structure of the unborn child. It will present tooth tissue with incompletely formed layers, covered with streaks or yellow or brownish spots.
Fluoride: given in optimal amounts, fluoride has beneficial effects on preventing the development of carious lesions. However, in the event of overdose, so-called fluoride poisoning occurs, which is responsible for white, yellow or brown spots, in number and size directly proportional to the concentration and duration of administration. Fluoride treatment should be recommended by the pediatrician or dentist, with systematic checking for side effects.
In the case of internal dyschromia, the recommended treatment is bleaching, carried out in the dental surgery. Professional brushing and scaling only act on the enamel, whereas the origin of this type of dyschromia is at the dentinal level.
Some patients have yellowish teeth from birth. The shade is darker but evenly spread. For these too, whitening treatment will be carried out in the dentist’s surgery, under direct supervision of the results.
