Human Dentition Or Teeth

Human Dentition or Teeth

Human has two sets of teeth. Primary (milky, baby or deciduous)teethform during the child’s formation in the womb. Permanent or adult teeth form after birth.

When do primary teeth appear in the mouth and how many they are?

Primary teeth appear in the mouth on average from 6 months till 2.5 years of age. They are 10 in each jaw, 5 on each side.

They are divided into 3 categories:

Incisor: 2 on each side

Canine: 1 on each side

Molar: 2 on each side

The primary teeth start to shed at 6 years of age.

Lower incisors are the first to shed and upper canines are the last ones.

When each primary tooth erupts and when they shed?

The table below shows you the time of eruption and shedding of each primary tooth in each jaw:

Tooth	Erupt in the mouth	Shedding time
Upper Central Incisor	8-12 Month	6-7 years
Upper Lateral incisor	9-13 months	7-8 years
Upper canine	16-22 months	10-12 years
Upper first molar	13-19 months	9-11 years
Upper second molar	25-33 months	10-12 years
Lower Central incisor	6-10 months	6-7 years
Lower lateral incisor	10-16 months	7-8 years
Lower canine	17-23 months	9-12 years
Lower first molar	14-18 months	9-11 years
Lower second molar	23-31 months	10-12 years

**** American Dental Association *****

What are permanent teeth and when they start to appear in the mouth?

As the name suggests these teeth don’t change after eruption and if lost will not be replaced naturally by other tooth.

They are 32 in number (including the wisdom teeth). Permanent teeth start to replace primary ones at around age 6 years. At the same time the first permanent molar will erupt behind the primary second molar.

Permanent teeth are divided into 4 categories:

Incisor: 2 on each side and replacing the 2 primary incisors

Canine: 1 on each side and will replace the primary canine

Premolar: 2 on each side and replace the primary molars

Molar: 3 on each side and do not replace any primary teeth

When each permanent tooth erupts in the mouth?

The table below shows each permanent tooth and its eruption time. As well which primary teeth they replace.

Permanent tooth	Eruption time	Replaced primary tooth
Upper Central incisor	7-8 years	Primary central incisor
Upper Lateral incisor	8-9 years	Primary lateral incisor
Upper canine	11-12 years	Primary canine
Upper first premolar	10-11 years	Primary first molar
Upper Second premolar	10-12 years	Primary second molar
Upper first molar	6-7 years	Doesn’t replace any primary tooth
Upper second molar	12-13 years	Doesn’t replace any primary tooth
Upper third molar	17-21 years	Doesn’t replace any primary tooth
Lower Central incisor	6-7 years	Primary central incisor
Lower lateral incisor	7-8 years	Primary lateral incisor
Lower canine	9-10 years	Primary canine
Lower first premolar	10-12 years	Primary first molar
Lower second premolar	11-12 years	Primary second molar
Lower first molar	6-7 years	Doesn’t replace any primary tooth
Lower second molar	11-13 years	Doesn’t replace any primary tooth
Lower third molar	17-21 years	Doesn’t replace any primary tooth