When the correct amount of fluoride is ingested, it can help prevent tooth decay and the formation of caries. However, if too much is consumed, especially by young children, dental fluorosis can occur. The causes damage to the enamel of the teeth, pitting and strong staining. Only children younger than 8 years old are at risk of dental fluorosis because the first, milk teeth are softer and more prone to damage than the permanent adult teeth that are forming under the gums. Once the permanent teeth emerge, excess fluoride cannot damage the stronger enamel. Adults, adolescents and older children are therefore not prone to dental fluorosis.