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Types of Teeth
Tooth is a living part of
body containing nerves and blood vessels.
The part that is visible in the mouth is the
crown and the longer portion anchored inside
the gum and the bone is the root.
The outermost hardest white cover is known
as the enamel.
The inner relatively less hard is the
dentin.
It surrounds the pulp containing blood
vessels and nerves of the tooth.
The pulp tissue is connected to the
circulatory and nervous system via a foramen
at the apex of the tooth. Surrounding the
roots, which are also made up mainly of
dentin, there is a thin bone like layer
called cementum.
The jawbone is connected with cementum
through a shock-absorbing membrane, the
periodical ligament.
There are four different types of teeth in
human beings. They vary in shape and size
according to their particular function. They
are:
Incisors: They are front teeth, four
in the upper arch and four in the lower
arch. They are shaped to bite and cut food
into small pieces.
Canines: They are conical teeth at
the corner of the mouth. Their function is
to tear or shred food.
Premolars: These are two on each side
of both the jaws just behind the canines.
These teeth have two cusps and the function
is to hold and crush the food.
Molars: They are three in number on
each side of the jaws and have bigger
chewing surfaces for cutting food into
smaller particles.
There are two sets of teeth:
Deciduous - The first to appear are
Milk Teeth and are helpful to the child not
only in terms of chewing but also in
providing guidance to the developing jaw and
permanent dentition. The first milk tooth
appear at about 6 months of age and then
subsequently all 20 teeth erupt upto two and
half years. The milk dentition has 2
incisors, one canine and 2 molars on each
side of the jaw that makes 5 teeth on each
side and a total of 20 teeth in the mouth.
The milk teeth are lighter in colour as
compared to permanent teeth.
Permanent - At six years of age,
natural shedding of milk teeth and the
eruption of permanent teeth begins which
continues till the age of 12 years. The
first permanent molar erupts at six years
just behind the milk teeth on all four sides
of the jaw. At this time the milk teeth
start falling and permanent teeth start
replacing them. Subsequently most of the
permanent teeth erupt till 12 years of age.
The second molars erupt behind the first
molar at about 12-13 years and the third and
last molar (wisdom teeth) erupt between
18-25 years. The permanent teeth are larger
and darker in colour as compared to milk
teeth. There are two incisors, one canine,
two pre-molars and three molars making eight
teeth in each quadrant and a total of
thirty-two in permanent dentition.
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Overview
