A great majority of the population is becoming increasingly aware and interested in dental esthetics today. Tooth whitening procedures provide a conservative means to improve dental esthetics.
These whitening procedures can be useful on their own or as an adjunct to other restorative procedures.
Tooth whitening is a blanket term for the process resulting in a material becoming similar in color to a preferred or standard white regardless of the means used.
Tooth bleaching has been defined as chemically induced whitening due primarily to the effects of carbamide peroxide which releases about one third of its content as hydrogen peroxide.
As the general population becomes more aware of dental esthetics this may be accompanied by an increase in the demand for esthetic procedures as well as increased expectations for treatment outcomes.
► DENTAL ESTHETICS: 10 commandments of smile esthetics
It is therefore pertinent for dental providers to understand the science behind tooth whitening procedures, their specific indications, success rates, rates of rebound, potential side effects and limitations.
The aim of this paper is to provide a summary of the available literature on tooth whitening procedures, their specific indications, limitations as well as side effects.
Classification of dental staining
Dental discoloration is generally classified as extrinsic or intrinsic.
Extrinsic staining is of external origin and is often superficial in nature.
Iatrogenic discoloration can occur due to dental treatment such as pulp extirpation which induces hemorrhage into dentin, remaining pulpal tissue during root canal procedures, root canal irrigants or root canal restorative materials.
Combining irrigants containing sodium hypochlorite and chlorhexidine may lead to a reddish-brown precipitate.
Some endodontic materials that contain tetracycline for example Ledermix, Endofill, Zinc Oxide Eugenol, Tubuliseal, Gutta Percha, Grey Mineral Trioxide Aggregate can lead to intrinsic discoloration.
