Dental fluorosis

Dental fluorosis is a common disorder, characterized by hypomineralization of tooth enamel caused by ingestion of excessive fluoride during enamel formation.(142) Dental fluorosis is a common disorder, characterized by hypomineralization of tooth enamel caused by ingestion of excessive fluoride during enamel formation. It appears as a range of visual changes in enamel causing degrees of intrinsic tooth discoloration, and, in some cases, physical damage to the teeth. The severity of the condition is dependent on the dose, duration, and age of the individual during the exposure. The 'very mild' (and most common) form of fluorosis, is characterized by small, opaque, 'paper white” areas scattered irregularly over the tooth, covering less than 25% of the tooth surface. In the 'mild' form of the disease, these mottled patches can involve up to half of the surface area of the teeth. When fluorosis is moderate, all of the surfaces of the teeth are mottled and teeth may be ground down and brown stains frequently 'disfigure' the teeth. Severe fluorosis is characterized by brown discoloration and discrete or confluent pitting; brown stains are widespread and teeth often present a corroded-looking appearance. People with fluorosis are relatively resistant to dental caries (tooth decay caused by bacteria), although there may be cosmetic concern. In moderate to severe fluorosis, teeth are weakened and suffer permanent physical damage. The adequate diagnosis of fluorosis can be diagnosed by visual clinical examination. This requires inspection of dry and clean tooth surfaces under a good lighting. There are individual variations in clinical fluorosis manifestation which are highly dependent on the duration, timing, and dosage of fluoride exposure.There are different classifications to diagnose the severity based on the appearances. The clinical manifestation of mild dental fluorosis is mostly characterised a snow flaking appearance that lack a clear border, opaque, white spots, narrow white lines following the perikymata or patches as the opacities may coalesce with an intact, hard and smooth enamel surface on most of the teeth. With increasing severity, the subsurface enamel, all along the tooth becomes more porous. Enamel may appear yellow/ brown discolouration and/ or many and pitted white-brown lesions that look like cavities. They are often described as “mottled teeth”. Fluorosis does not cause discolouration to the enamel directly, as upon eruption into the mouth, affected permanent teeth are not discoloured yet. In dental enamel, fluorosis causes subsurface porosity or hypomineralizations, which extend toward the dentinal-enamel junction as severity increases. Hence, affected teeth are more susceptible to staining. Due to diffusion of exogenous ions (ex, iron and copper), the stains would develop into the abnormally porous enamel. The differential diagnosis for this condition includes: The two main classification systems are described below. Others include the tooth surface fluorosis index (Horowitz et al. 1984), which combines Deans index and the TF index; and the fluorosis risk index (Pendrys 1990), which is intended to define the time at which fluoride exposure occurs, and relates fluorosis risk with tooth development stage. Dean's fluorosis index was first published in 1934 by H. Trendley Dean. The index underwent two changes, appearing in its final form in 1942. An individual's fluorosis score is based on the most severe form of fluorosis found on two or more teeth. Proposed by Thylstrup and Fejerskov in 1978, the TF index represents a logical extension of Dean's index, incorporating modern understanding of the underlying pathology of fluorosis. It scores the spectrum of fluorotic changes in enamel from 0 to 9, allowing more precise definition of mild and severe cases. Dental fluorosis is caused by a higher than normal amount of fluoride ingestion whilst teeth are forming. Primary dentine fluorosis and enamel fluorosis can only happen during tooth formation, so fluoride exposure occurs in childhood. Enamel fluorosis has a white opaque appearance which is due to the surface of the enamel being hypomineralised.