Ultimate Guide to Teething

Teething is a natural process babies go through, but it differs a little for each one. See more parenting pictures.
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Teething, or the eruption of a baby's first teeth through the periodontal membrane, is one of life's earliest growing pains and can be just as taxing for parents as it is for babies. While some babies may bounce through this stage happily unaware, others may experience discomfort and anxiety.

A baby can begin teething as early as 3 months and may continue through the age of 3 years, which is when most kids should have developed all 20 primary teeth. Primary teeth are also referred to as baby teeth or deciduous teeth because they are temporary and will eventually be replaced by permanent teeth.

Children keep their primary teeth until around the age of 6, when their permanent teeth are ready to make their appearance. When this happens, primary teeth become loose and are expelled, or exfoliated, from the gums. The process of developing permanent teeth is much longer than that of primary teeth and can last well into adulthood, concluding with the appearance of wisdom teeth, or third molars. This set of molars typically appears between the ages of 17 and 21 and can be troublesome because they often come in misaligned and displace other teeth. This is why it is common for wisdom teeth to require extraction.

But this process actually begins in utero, when teeth begin the first of three stages of development. The next page examines these stages and explores the biology and mechanics of teething.