Development of baby teeth

Both baby teeth (deciduous or milk teeth) and permanent teeth have fairly well-defined times of eruption. The ages listed are the normal ages that a baby tooth emerges.

 

UPPER

ERUPTS BY

 

LOWER

ERUPTS BY

Central incisor

8-10 Mo

 

Central incisor

6-9 Mo

Lateral incisor

8-10 Mo

 

Lateral incisor

5-21 Mo

Canine (Cuspid)

16-20 Mo

 

Canine (Cuspid)

5-21 Mo

First molar

15-21 Mo

 

First molar

15-21 Mo

Second molar

20-24 Mo

 

Second molar

20-24 Mo

 

 Development of permanent teeth

Both baby and permanent teeth have fairly well-defined times of eruption. The ages listed are the typical ages that an adult tooth has fully emerged.

UPPER and LOWER ERUPTS BY
Central incisor 7th Yr
Lateral incisor 8th Yr
Canine (Cuspid) 11-12th Yr
First premolar (Bicuspid) 9th Yr
Second premolar(Bicuspid) 10th Yr
First molar 6th Yr
Second molar 12-13th Yr
Third molar 17-25th Yr

Adult Teeth

An adult has 32 permanent teeth. The incisors and canine teeth tear and cut food, and premolars and molars are used to grind and crush. The four back teeth are called the wisdom teeth (or third molars).

 

 

Internal Structure of Teeth

The three main parts of a tooth are the crown, neck and root. The crown (the part of the tooth you see - above the gums) is covered by a protective, bony layer of enamel, and the root of the tooth is covered by a sensitive, bonelike substance called cementum. A hard substance known as dentin surrounds the pulp, which contains nerves (sensing heat, cold, pain, and pressure) and blood vessels (nourishing the tooth). The gums (or gingiva) fit around the teeth, and the roots of the teeth fit into sockets in the jawbone. Lining the sockets is a tissue called periodontium