Difference between Milk Teeth and Permanent Teeth

Teeth are an important part of our body without them we won't be able to chew our food. The teeth, which we have at an early age (6 months to 5 years) and do not stay for a longer duration are called milk teeth. They are replaced by a new set of teeth called permanent teeth, let us see how they differ from each other.

Milk Teeth

The first set of teeth is called milk teeth. These teeth are small in size as they erupt at an early age. Teeth start erupting from age six months onward up to the age of 5 years. These are temporary teeth, so, they start falling by the age of 6 years till the age of 12-13 years.

Crown of milk teeth:

• Crown of primary teeth is lighter in color, like the milky white color. The refractive index of milk teeth is 1 which is the same as the refractive index of milk.
• The number of milk teeth is 20. The teeth formula is 2-1-0-2. It means two insiders, one canine, O premolar, and two molar teeth. So, the premolar and third molar are absent in milk teeth. These teeth are smaller in size. The first two teeth that are erupting in the oral cavity are mandibular incisor teeth and cuspids are conical in milk teeth.
• Milk teeth have narrow occlusal tables (chewing surfaces of teeth). The occlusal plane is relatively flat. Occlusal plane correction is easy in milk teeth.
• Molars of milk teeth are more bulbous. The size of the first molar is less than the second molar.
• The thickness of the enamel teeth is less up to 1 millimetre. These teeth have broad contact areas and are situated gingivally. Mamelons are also absent in milk teeth.

Roots of milk teeth:

• Roots are larger in size and cylindrical.
• Root trunk is smaller for milk teeth.
• Furcation area is higher in milk teeth. So cavity preparation chances are more.
• The phenomenon which is seen in milk teeth is physiological resorption.

Pulp of milk teeth:

• Pulp chambers are larger, and pulp cones are also closer to the outer surface in milk teeth. That's why there is a high chance of cavity preparation.
• There is a high degree of cellularity and vascularity. The cellularity is more so the chances of repair are more. The high vascularity means there is a faster spread of infections. Cellularity is good for milk teeth, and vascularity is bad for milk teeth.
• There are more branches, so the root canal is more complicated. The accessory canal is located in the furcation area. The bone loss occurs in the furcation area.
• Enamel and dentin are less mineralized.
• The density of nerves intervention is less due to this milk teeth are less sensitive for operative procedures.

Permanent Teeth

The second set of teeth that replaces milk teeth is called permanent teeth. Milk teeth fall out one by one, from six to twelve years of age and new teeth grow in their place. These new teeth are called permanent teeth, which have a set of 32 teeth with 16 teeth in each jaw. Permanent teeth last throughout life and are bigger in size.

Crown of permanent teeth:

• They are a little bit darker in color.
• Teeth start erupting from the age of six and continue erupting up to the age of 25-30 years.
• The number of permanent teeth ranges from 28 to 32. Some people have 28 permanent teeth, and few people have 32 permanent teeth. The first teeth are erupting in the oral cavity are the mandibular first molar, which is actually the first permanent teeth.
• These teeth are large in size. The teeth formula is 2-1-2-3. It means two insiders, one canine, two premolar, and three molar teeth. The third molar is optional it does not actually appear in every individual. Molars of permanent teeth are less constricted. The size of the first molar is greater than the second molar.
• Cuspids are less conical for permanent teeth. They have a wider occlusal table. The occlusal plane is sometimes deep, so, it is more curve. Occlusal plane correction is difficult in permanent teeth.
• The thickness of the enamel teeth is thicker. Their thickness is above 2-3 millimetres. The contact point between teeth is more occlusal. Mamelons are present in permanent teeth.

Roots of permanent teeth:

• Roots are short in size and bulbous.
• Root trunk is larger in permanent teeth.
• The physiological resorption phenomenon is absent in permanent teeth.

Pulp of permanent teeth:

• Pulp chambers are smaller, and pulp cones are also away from the outer surface in permanent teeth. So there are fewer chances of cavity preparation.
• There is less degree of cellularity and vascularity. Less cellularity means the chances of repair are less. Whereas, less vascularity means there is a slower spread of infections. Cellularity is bad for permanent teeth, and vascularity is good for permanent teeth.
• The root canal is well defined with a fewer number of branches. The accessory canal is located at the area apical third. The bone loss occurs in the apical area.
• Enamel and dentin are more mineralized.
• Nerves are denser in the permanent teeth. Therefore, they are more sensitive to operative procedures.

Types of teeth (incisors, canine, molar and premolar)

1. Incisors teeth: Front Teeth are called Incisors. Humans have eight incisors teeth. Four teeth are on the upper side and four teeth are on the lower side. These teeth are used to bite food. The surface of the teeth is flat.
2. Canine teeth: They sit next to incisors. Canines are teeth, which are situated on the left and right sides of incisors. Humans have four canines; two on the upper side and two on the lower side of the jaw. Canine has a sharp, pointy surface for tearing food.
3. Premolar teeth: Premolar has to sit next to the canine. Four premolars at the upper side and four premolars at the downside. The premolar is bigger than canine and incisors. This is used to bite and tearing food.
4. Molar: Molars are located next to the premolar. Humans have 12 molars; six molars on the upper side and six on the lower side. Molar is bigger than premolar.

Tooth decay:

When humans eat food, after eating food, some food remains in the mouth. If we do not clean the mouth the bacteria start to grow, and the number of bacteria increases with time. These bacteria start to produce acid, which damages the teeth. Due to tooth decay, humans suffer from toothache and tooth loss. Mainly sweet food is responsible for tooth decay, like chocolate, candy, soft drinks, ice cream, etc. To avoid tooth decay, clean the mouth after eating food. Try to avoid drinks and sweet food which harm the tooth.

Difference between milk teeth and permanent teeth