There are many causes of tooth discoloration. The most common are: stimulants (apart from cigarettes, black coffee and tea, excess potatoes and tomatoes in the diet), changes in saliva pH (too low pH caused by stress and acidic diet), use of oral hygiene products (chlorhexidine in pastes or liquids for rinsing), poor oral hygiene and associated cervical caries. Drug-induced discoloration of the teeth is also possible, resulting from taking oxytetracycline, tetracycline, demeclocycline (yellow-brown discoloration) or chlorotetracycline (gray-brown discoloration). In order to start proper treatment, it is necessary to visit a doctor and verify what type of discoloration this is. Sometimes it is sufficient to remove the cause by stopping medication, liquids, changing diet or hygiene habits, but most often professional cleansing (sandblasting) or proper treatment in the form of filling or veneers is recommended.