Whether you are a parent of a six month old, a six year-old, or a sixteen year-old, this post can be useful to you! This week, we’re discussing the patterns associated with primary, mixed, and permanent dentition. But first, what is dentition? Dentition is defined as the arrangement of teeth and includes the type and letter or number associated with them. Each tooth has its own name and letter or number associated with it to make up its special identity. While every mouth is unique and different than anyone else, there is a general pattern the teeth follow, especially regarding eruption (when the teeth push through the gums) and exfoliation (when the tooth is lost). Now what does primary, mixed, and permanent mean?
Primary dentition = BABY teeth = identified as letters
Permanent dentition = ADULT teeth = identified as numbers
Mixed dentition = a combination of BABY and ADULT teeth (letters and numbers)
Each tooth (baby and permanent) has its own special name. The American Dental Association has created the image below to help you visualize by name each baby tooth in your little one’s mouth.
The two teeth in the center are called “central incisors”, which makes sense, right? Next to the central incisors are the “lateral incisors”. Next to the lateral incisors are the “canines” or “cuspid” teeth. Next to the canines are the “first molars”, and lastly, the “second molars”. There are a total of 20 baby teeth.
Let’s talk PRIMARY ERUPTION PATTERNS:
When can you expect your child’s teeth to come in? The lovely @sll.stories (Instagram) has created this fun and colorful chart to help you know when to expect a new tooth to erupt between ages 6 months and 3 years. You may even want to print it out and check off each tooth as it erupts!
You can also follow along with this chart for eruption and exfoliation patterns.
The American Dental Association has also developed this chart and includes when to expect a baby tooth to loosen up and fall out (shed).
It is important to remember, these charts include ranges of when teeth commonly erupt and shed. That does not necessarily mean your child will follow it exactly. If you are concerned about the patterns of your child’s teeth, it is best to consult with your local dental provider.
PERMANENT ERUPTION PATTERNS:
Primary teeth stay with your little one until they are about 6-7 years old. Then what happens? They become loose, your child wiggles them out, and the tooth fairy makes a visit! This process is fun and can be a really rewarding way to encourage your child to wiggle those loose teeth out when they are ready. You can typically expect the bottom two front teeth (central incisors) to become loose and shed first. This happens around 6-7 years old. Sometimes, the permanent teeth will even begin erupting behind the primary teeth before they fall out and your child will have essentially an extra row of teeth for a little while. If you notice this occurring and the primary teeth are not loosening up, it may be best to contact your dental provider. However, most often your child will be able to wiggle out those tiny little baby teeth in order for the permanent teeth to make their way in.
As those bottom front teeth begin to fall out, you may also notice new permanent molars erupting in the back of the mouth, behind the baby second molars. These are the permanent first year molars and they erupt without replacing any teeth. Most of the time your child is not phased by their eruption, however, these are larger sized molars and can be uncomfortable. If your child seems bothered by them erupting, consult with your dental provider to be safe.
You can typically expect all permanent teeth, up to the second molars, to erupt by age 12 or slightly older.
The American Dental Association has designed this chart to explain when to expect all permanent teeth to be in place.
You’ll notice the first and second premolars are replacing the primary first and second molars. Premolars do not exist in the primary dentition. These are new teeth associated with adult teeth only. However, just like in the primary phase, the permanent teeth are also named as central incisors, lateral incisors, canines, and molars, with the addition of premolars!
Wisdom teeth, also known as third molars, may begin to erupt or cause pressure behind the second molars between ages 17-21. Some people will develop all four third molars, while others have fewer. If your teenager begins to have discomfort far in the back of their mouth, be sure to follow-up with your dental provider. These teeth may need to be removed if there is not adequate space in the mouth for them to erupt.
MISSING OR EXTRA TEETH?
Some teeth may be congenitally missing, meaning the tooth never developed and this can be hereditary. On the contrary, sometimes there can be supernumerary teeth, meaning an extra tooth develops. While this is more rare than congenitally missing teeth, it can occur anywhere in the mouth. If you are aware of any missing teeth or extra teeth in your family, be sure to have this discussion with your dental provider early on so they can monitor eruption patterns more closely.
You’ll notice your child in the primary dentition phase from roughly age 3, once all primary teeth have erupted to about age 6 or 7, right before they lose their first tooth and enter the mixed dentition phase. The mixed dentition phase typically lasts between ages 6 to 12 while all baby teeth are exfoliating and permanent teeth are erupting. The permanent dentition phase is the final phase and lasts through adulthood. There are a total of 20 primary teeth, and up to 32 permanent teeth (if you include all four third molars)
While baby teeth have a very important role in helping with speech development, serving as a space holder for permanent teeth, and allowing your child to indulge in nutritious foods, it is important to remember to help your child keep them clean and cavity free. Remember to brush twice a day and floss nightly to keep the sugar bugs away. Grin has thoughtfully designed brushes to meet whichever dentition phase your child is in: primary, mixed, and adult. I encourage you to check them out!
About the Author
Kristen Cockrell is a Registered Dental Hygienist with a passion for preventive pediatric dentistry and oral health education. Kristen has recently graduated with a master’s degree in dental hygiene education at the University of North Carolina at Chapel Hill. Social media account Instagram: @kristenwcockrell