Digestion and Absorption

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Dentin : The

tissue beneath

the enamel

Pulp : Mass of

connective tissue

in center of tooth

beneath dentin

layer

Enamel : The

hard chewing

surface of teeth.

Nature & mode of arrangement of teeth is called dentition.

Human dentition is Thecodont, Heterodont & Diphyodont. (NEET 2018)



Thecodont : It means teeth are placed in the jaw sockets.



Heterodont : It means different kinds of teeth are present.

They are incisors (I) for cutting, canines (C) for tearing, premolars (PM) &

molars (M) for mastication.

Premolars & molars are collectively called as cheek teeth which have cusps.

It means teeth appear twice in the lifetime. They are milk (deciduous)

teeth and permanent teeth. Milk teeth (20 in number) are erupted at 6-7

months of birth. They are replaced by permanent teeth (32 in number) at

the age of 6-7. Last 4 molars (wisdom teeth) appear only at the age of 18.

Diphyodont

Teeth appearing just once in lifetime.

Monophyodont

DENTAL FORMULA :

It explains the kinds and number of teeth.

HUMAN DENTAL FORMULA (OF PERMANENT TEETH) :

2

1

2

3

2123

 I  C PM

M

2

32

2

1

2

3

2123





×

=









DENTAL FORMULA OF MILK DENTITION :

2

1

0

2

2102

 I  C PM

M

2

20

2

1

0

2

2102





×

=









DENTAL FORMULA OF MONOPHYODONT

0021

0021

=

Molars

Premolars

Canine

Incisor

Socket

of jaw