Human tooth development the low levels of fluoride incorporation and very mild fluorosis makes the tooth more resistant to demineralization and subsequent decay. Deficiencies of nutrients can have a wide range of effects on tooth development. In situations where calcium, phosphorus, and vitamin D are deficient, the hard structures of a tooth may be less mineralized. A lack of vitamin A can cause a reduction in the amount of enamel formation. Fluoride ingestion has been noted to delay eruption of teeth for as much as a year or more from the accepted eruption dates since the initial 1940s fluoridation trials. Researchers theorize that
Human tooth Human tooth The human teeth function to mechanically break down items of food by cutting and crushing them in preparation for swallowing and digesting. Humans have four types of teeth: incisors, canines, premolars, and molars, each with a specific function. The incisors cut the food, the canines tear the food and the molars and premolars crush the food. The roots of teeth are embedded in the maxilla (upper jaw) or the mandible (lower jaw) and are covered by gums. Teeth are made of multiple tissues of varying density and hardness. Teeth are among the most distinctive (and long-lasting) features of