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Teething is the process by which an infant's first teeth (the deciduous teeth, often called "baby teeth" or "milk teeth") sequentially appear by emerging through the gums, typically arriving in pairs. Teething may start as early as six months or as late as eight months. The first 10 teeth typically appear between six and nine months. It can take several years for all 20 teeth to complete the tooth eruption. Though the process of teething is sometimes referred to as "cutting teeth", when teeth emerge through the gums they do not cut through the flesh. Instead, hormones are released within the body that cause some cells in the gums to die and separate, allowing the teeth to come through.〔(Teething ) ''National Health Service'' of England〕 Teething may cause a slightly elevated temperature, but not rising into the febrile range, . Higher temperatures during teething are due to some form of infection, such as a herpes virus, initial infection of which is extremely widespread among children of teething age. ==History== Teething used to be considered (wrongly) a cause of death, as many children died in the first years of life, at the same time as teething occurs. "The tendency in the past to attribute serious disease to teething was so prevalent that in 1842 teething was the registered cause of death in 4.8% of all infants who died in London under the age of 1 year and 7.3% of those between the ages of 1 to 3 years according to the Registrar General's report."〔 Ironically, while teething is a natural process which creates little more than discomfort, some methods for relieving teething pain have caused serious harm and even death. Old remedies for teething include "blistering, bleeding, placing leeches on the gums, and applying cautery to the back of the head". In the sixteenth century the French surgeon Ambroise Paré introduced the lancing of gums using a lancet, in the belief that teeth were failing to emerge from the gums due to lack of a pathway, and that this failure was a cause of death. This belief and practice persisted for centuries, with some exceptions, until towards the end of the nineteenth century lancing became increasingly controversial and was then abandoned, although as late as 1938 an Anglo-American dental textbook advised in favour of lancing, and described the procedure.〔 In the first half of the twentieth century, teething powders in the English-speaking world often contained calomel, a form of mercury. It was removed from most powders in 1954 when it was shown to cause "pink disease" (acrodynia), a form of mercury poisoning. Teething toys have a long history. In England in the 17th–19th centuries, a ''coral'' meant a teething toy made of coral, ivory, or bone, often mounted in silver as the handle of a rattle.〔''OED''; (Examples from the Metropolitan )〕 A museum curator has suggested that these substances were used as "sympathetic magic" and that the animal bone could symbolize animal strength to help the child cope with pain. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Teething」の詳細全文を読む スポンサード リンク
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