Eighty-eight (1.96%) out of 4,500 patients had teeth stained by tetracycline. The majority had yellowish-brown stains (59.1%), whilst 37.5% had greyish-brown and 3.4% had black stains. A large number of teeth (79.6%) were stained up to two-thirds of their crowns. The deciduous teeth, permanent incisors and first molars were most commonly affected (73.9%). Teeth are only stained by tetracycline if this drug is administered during their calcification periods. For aesthetic reason, the drug should not be prescribed from the fourth month of pregnancy till the seventh year of life. The social embarrasment due to such discolouration may be overcome by tooth bleaching and construction of tooth facings and crowns.
Advances in endodontic materials and techniques are at the forefront of endodontic research. Despite continuous improvements, tooth discolouration, especially in anterior teeth, is considered an undesirable consequence following endodontic treatment as it creates a range of aesthetic problems. This article aims to discuss the intrinsic and internalized tooth discolouration caused by endodontic procedures, and to address the discolouration potential of materials used during root canal treatment, including root canal irrigants, intra-canal medicaments, endodontic and post-endodontic filling materials. In addition, the discolouration patterns caused by combined endodontic and nonendodontic aetiological factors are discussed. The recommended guidelines that should be followed by dental practitioners to prevent and manage tooth discolouration are also outlined.