Deciduous Teeth vs. Permanent Teeth

What's the Difference?

Deciduous teeth, also known as baby teeth or milk teeth, are the first set of teeth that erupt in a child's mouth. They typically start to appear around six months of age and are eventually replaced by permanent teeth. Deciduous teeth are smaller in size and have a whiter appearance compared to permanent teeth. They serve as placeholders for the permanent teeth and help in chewing and speech development. On the other hand, permanent teeth are the second set of teeth that replace the deciduous teeth. They start to erupt around the age of six and continue to develop until early adulthood. Permanent teeth are larger, stronger, and more durable than deciduous teeth. They are designed to last a lifetime and play a crucial role in biting, chewing, and maintaining proper oral health.


AttributeDeciduous TeethPermanent Teeth
Number of Teeth2032
AppearanceSmaller and whiterLarger and yellower
Timing of EruptionErupt between 6-12 monthsErupt between 6-21 years
Root DevelopmentRoots are less developedRoots are fully developed
ReplacementShed and replaced by permanent teethNo replacement, permanent teeth are final
FunctionAid in chewing and speech developmentMainly used for chewing and biting

Further Detail


Teeth play a crucial role in our overall health and well-being. They help us chew food, speak clearly, and maintain the structure of our face. However, did you know that humans have two sets of teeth throughout their lifetime? The first set, known as deciduous teeth or primary teeth, are the ones we develop as infants and children. These teeth are eventually replaced by permanent teeth, also known as adult teeth. In this article, we will explore the attributes of deciduous teeth and permanent teeth, highlighting their similarities and differences.

Development and Eruption

Deciduous teeth begin to develop during the prenatal period and usually start erupting around six months of age. The eruption process continues until around the age of three, when all 20 deciduous teeth have emerged. On the other hand, permanent teeth start developing during early childhood but do not erupt until around the age of six. The eruption of permanent teeth continues throughout adolescence and early adulthood, with the last molars, commonly known as wisdom teeth, erupting between the ages of 17 and 25.

Number and Types

Deciduous teeth consist of a total of 20 teeth, including 8 incisors, 4 canines, and 8 molars. These teeth are smaller and whiter compared to permanent teeth. On the other hand, permanent teeth consist of 32 teeth, including 8 incisors, 4 canines, 8 premolars, and 12 molars (including 4 wisdom teeth). The additional premolars and molars in permanent dentition allow for more efficient chewing and grinding of food.

Size and Shape

Deciduous teeth are generally smaller in size and have a more rounded shape compared to permanent teeth. This is because the jawbone of a child is smaller and cannot accommodate the larger permanent teeth. As a child grows, the jawbone expands, allowing for the eruption of larger and more robust permanent teeth. The shape of deciduous teeth also aids in the development of proper speech patterns during early childhood.

Root Structure

The root structure of deciduous teeth is relatively shallow compared to permanent teeth. This is because deciduous teeth are meant to be eventually replaced, and their roots resorb as the permanent teeth develop beneath them. On the other hand, permanent teeth have longer and stronger roots that anchor them firmly in the jawbone. The deep root structure of permanent teeth provides stability and support for a lifetime.

Enamel and Dentin Composition

The composition of enamel and dentin, the two main components of teeth, differs between deciduous and permanent teeth. Deciduous teeth have a thinner layer of enamel and dentin compared to permanent teeth. This makes deciduous teeth more susceptible to tooth decay and cavities. Permanent teeth, on the other hand, have a thicker layer of enamel and dentin, providing better protection against dental issues.

Function and Lifespan

Deciduous teeth serve as placeholders for permanent teeth and aid in the development of proper speech and chewing abilities. They are designed to be temporary and start falling out naturally as permanent teeth begin to erupt. The lifespan of deciduous teeth varies, but they typically start to shed around the age of six and are completely replaced by permanent teeth by the age of 12 or 13.

Permanent teeth, on the other hand, are meant to last a lifetime. They are larger, stronger, and better suited for the demands of adult life. Permanent teeth enable efficient chewing and grinding of food, contribute to proper speech patterns, and maintain the facial structure. However, it is important to take care of permanent teeth through regular dental hygiene practices, as they are still susceptible to dental issues such as cavities, gum disease, and tooth loss if not properly maintained.


Deciduous teeth and permanent teeth have distinct attributes that make them suitable for different stages of life. While deciduous teeth serve as temporary placeholders, permanent teeth are designed to last a lifetime. Understanding the differences between these two sets of teeth can help us appreciate the importance of proper dental care and hygiene throughout our lives. Whether it's the eruption process, number and types of teeth, size and shape, root structure, or composition, each aspect contributes to the unique functions and characteristics of deciduous and permanent teeth.

Comparisons may contain inaccurate information about people, places, or facts. Please report any issues.