Teeth 101: All You Need To Know
What They Are:
Located in the mouth, teeth are small, calcifiedstructures with roots that extend into the gums and jawbone.
A tooth consists of many layers. The outer layer, called the enamel, is made of hard crystal. The second layer, called dentin, is softer. The pulp, which is found in the middle of the tooth, contains blood vessels and nerves that conduct sensations of pain.
When They Appear:
The 1st set of teeth, called primary, deciduous or baby teeth, typically begin to appear between the age of 6 months and 1 year. Most children have a full set of 20 primary teeth by the time they are 3 years old.
Primary teeth fall out when a child is between the ages of 6 – 14 years and are replaced by 32 permanent or adult teeth.
The last of the permanent teeth to appear are called “third molars” or “wisdom teeth” which erupt through the gums between 17 – 21 years of age.
Anomalies, ethnicity and heredity can influence when a child sheds their primary teeth and when their permanent teeth emerge.
The Four Classes of Teeth & What They Do:
There are four classes of teeth.
- Incisors: These are the four teeth located in the center of the upper and lower jaws. They have a shovel shaped appearance with sharp, thin edges that work like scissors to chew and cut through food.
- Canines: Located just outside the incisors, canines consist of 4 teeth – 2 are located in the top jaw and 2 in the bottom jaw. Also called cuspids or eye teeth, they have a single cusp (the pointed tip on the biting surface of the teeth). These teeth are long and sharp making them useful for tearing and shredding food. Cuspids are the longest and most stable of teeth in the mouth.
- Premolars: Known as Bicuspids (because they have 2 cusps), these eight teeth are located between the upper and lower canines and molars. There are 2 bicuspids in each quadrant of the mouth (lower left, lower right, upper left, and upper right). Premolars have a flat surface that is used for chewing and grinding food into smaller pieces.
- Molars: Located in the back of the mouth, molars are the largest teeth. There are a total of 12 molars (6 molars in each jaw with 3 on each side) that gradually decrease in size from the first to third molar. First or six-year molars usually erupt when a child is around 6 years old. Second or twelve-year molars usually erupt when a child is approximately 12 years old. Third molars or ‘wisdom teeth’ are the last to come in at approximately age 17-21 . Molars are more rounded in shape than other teeth and because they have strong, flat surfaces they work like a grinder, mashing food into tiny bits.
Regular dental visits starting in infancy can lead to a lifetime of dental health.