Amelogenesis imperfecta (AI) represents a group of developmental conditions affecting the structure and clinical appearance of the enamel of all or nearly all the teeth in a more or less equal manner, and which may be associated with morphologic or biochemical changes elsewhere in the body.
The prevalence varies from 1:700 to 1:14,000, according to the populations studied.
The enamel may be hypoplastic, hypomineralised or both, and affected teeth may be discoloured, sensitive or prone to disintegration. AI exists in isolation or associated with other abnormalities as part of a syndrome.
In families with an X-linked form, it has been shown that the disorder may result from mutations in the amelogenin gene, AMELX. The enamelin gene, ENAM, is implicated in the pathogenesis of the dominant forms of AI. Autosomal recessive AI has been reported in families with known consanguinity.
Diagnosis is based on the family history, pedigree plotting and meticulous clinical observation. At present, genetic diagnosis is only available as a research tool.
It may be sporadic or show autosomal dominant, autosomal recessive or sex-linked inheritance.
The condition presents social and functional problems and leads to discomfort, but it may be managed by early vigorous intervention, both preventively and restoratively, with treatment continued throughout childhood and into adult life. In infancy, the primary dentition may be protected by the use of preformed metal crowns on posterior teeth. Longer-term care involves either crowns or, more frequently these days, adhesive, plastic restorations.
Last update: April 2007
- Pr Michael ALDRED
- Pr Agnès BLOCH-ZUPAN
- Pr Peter CRAWFORD