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How Are Deciduous Teeth Different From Permanent Teeth?

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After the age of six or so, deciduous teeth – also known as baby or primary teeth – fall out and are replaced by the permanent teeth. According to the American Dental Association (ADA), baby teeth will start showing up in a child's mouth starting around the age of six months and continuing until he or she is about six years old. The baby teeth play an important role in helping a child learn to chew and speak, and they also serve as placeholders, saving the spot for the permanent teeth that will eventually erupt. Here are several differences between the deciduous and the permanent teeth.


The enamel of the deciduous teeth is thinner than the enamel on permanent teeth according to the American Academy of Pediatrics (AAP). As a result, the primary teeth usually look a lot whiter than the permanent teeth. If a child has a mix of primary and permanent teeth, it's easy to see the permanent teeth tend to be more yellow than the primary. The thinner enamel on primary teeth, sugar intake and inadequate fluoride treatment can lead to rapid primary tooth decay – also known as baby bottle tooth decay – so it's importance to go to the dentist regularly to start good oral healthcare habits.


The shape of the teeth is also a tad different. When the front permanent teeth erupt, they usually have a number of small bumps on the top, known as mamelons, according to the AAP. The mamelons wear off over time, if the teeth fit together evenly. A dentist can also file the mamelons off to make sure the teeth look even.

Because the primary teeth are designed to fall out, they have differently shaped roots than permanent teeth, states KidsHealth. The roots of the deciduous teeth are thinner and shorter than the roots of the permanent teeth. According to Triangle Pediatric Dentistry, the short length of the tooth's roots makes it easier for them to dissolve when it's time for the tooth to fall out and ensures that the permanent teeth have space to form beneath them.

Number of teeth

Another big difference between the primary teeth and the permanent teeth is the number of them. According to the American Dental Association, people typically have 20 primary teeth and 32 permanent teeth, including four wisdom teeth. Part of the reason for the difference in number is that a child's mouth is much smaller than an adult's. Children don't have room for eight to 12 molars in the back of the mouth. But, as they grow older, the jaw lengthens to make space for the additional teeth.

Caring for the teeth

Since the primary teeth are designed to fall out, there's often the misconception they don't need care or protection. It's just as important, however, to provide tender, love and care for the primary teeth as you would care for the replacement teeth. If the teeth are lost or pulled out early, they can't act as space-savers and may not leave enough room for the permanent teeth, according to the ADA. A child might also have trouble with the alignment of his teeth.

To protect the deciduous teeth, get children started with a good oral hygiene routine early. Use a toothpaste to reduce the likelihood of developing cavities. It's also a good idea to have children see the dentist regularly. A dentist can keep an eye on the development of teeth and correct any problems with the baby teeth as needed.

Teaching children to take good care of their teeth from a young age will not only protect the teeth. It will also instill confidence in them about the health of their smile.