Article
This 29-year-old male manager requested cosmetic dentistry because of his appearance. His medical history was clear and he had not had orthodontic treatment. The social history included no current tobacco use and no alcohol consumption. Extra-oral examination revealed no significant abnormalities and specifically no cervical lymph node enlargement or cranial nerve, salivary or temporomandibular joint abnormalities.
His dentition was as shown (Figure 1) and a pink, grey and bluish discoloration was seen in upper right central and lateral incisors. There was no clinical evidence of periodontal attachment loss or pocketing.
Q1. What is the probable cause?
A1. The answer to what is the probable cause?
The main cause of tooth discoloration is external staining.
(b) Tooth resorption: resorption is a process by which all or part of the tooth structure (cementum and underlying dentine) is lost due to macrophage activation of osteoclasts. It usually affects a limited number of teeth only. The two main types of resorption are internal and external tooth resorption and trauma is the usual precipitant. Tooth movement may cause external resorption and pressure from pathological lesions, notably malignancies. Tooth trauma can cause intrapulpal haemorrhage and blood disintegration, the products of which, such as iron sulphides, are responsible for the discoloration. Necrosis by-products can penetrate the dentinal tubules and discolour the dentine. Trauma may be responsible for the loss of part of the tooth of the incisors, as seen in our patient. The pinkish colour can be explained by the presence of highly vascular coronal tissue visible through the residual enamel. Bacterial, mechanical or chemical irritation of the pulp can cause necrosis.
(c) Dental materials can also cause tooth discoloration.
(d) Metabolic diseases are rare, causing tooth discoloration. Alkaptonuria is a rare metabolic disorder, characterized by an incomplete metabolism of tyrosine and phenylalanine, thus promoting the accumulation of homogentisic acid and causing connective tissue, bone damage and brown-blue discoloration. Other metabolic diseases include porphyria, biliary atresia and other causes of hyperbilirubinaemia.