Dentition is the development of the primary
(also called baby teeth, milk or deciduous teeth) and permanent (adult)
teeth in the dental arch and their arrangement in the mouth. Typically,
humans have 20 primary teeth and 32 permanent teeth. |
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Tooth eruption
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Although tooth eruption occurs
at different times for different people, a general eruption moment
exists and pulls together in our
Guide.
Tooth eruption has three stages:
- The first, known as primary stage, occurs when only primary teeth are visible.
- Once
the first permanent tooth erupts into the mouth, the teeth are in the
mixed (or transitional) dentition.
- After the last primary tooth falls
out of the mouth, the teeth are in the permanent stage.
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Primary Dentition
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There are many different terms to describe
Primary Dentition
including: deciduous, baby, lacteal, and milk.
This stage starts on the arrival of the
low (mandibular) central incisors, usually at eight (6-10) months, and lasts
until the first permanent molars appear in the mouth, usually at six
(6-7)
years.
The 20 primary teeth typically erupt in the following order: (1) central
incisor,
(2) lateral incisor, (3) first
molar, (4)
canine, and (5) second molar (Dentition
Guide).
As a general rule, four teeth erupt for every six months of life,
low (mandibular) teeth erupt before upper (maxillary) teeth. Teeth erupt sooner in
females than males.
The teeth erupt sooner in
girls than boys.
Loss of the primary or deciduous
dentition usually occurs between 5 to 7 years of age, although some
children experience tooth loss earlier.
Children who lose their teeth at
a young age (older than 2 and younger than 5) are at a greater risk for
periodontal and gum disease.
The tooth buds of permanent
teeth develop below the primary teeth, close to the palate or tongue. |
Mixed Stage
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Mixed dentition starts when the first permanent molar appears in the
mouth, usually at six (6-7) years, and lasts until the last primary tooth is
lost, usually at eleven or twelve years.
Upper (maxillary) permanent teeth erupt in a different order from
low (mandibular) permanent
teeth.
Upper teeth erupt in the following order: (1)
first molar (2)
central incisor, (3)
lateral incisor, (4)
first premolar, (5)
second premolar, (6)
canine, (7)
second molar, and (8)
third molar (Dentition
Guide). |
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Low teeth erupt in the following order: (1)
first molar (2)
central incisor, (3)
lateral incisor, (4)
canine, (5)
first premolar, (6)
second premolar, (7)
second molar, and (8)
third molar (Dentition
Guide). |
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Since there are no premolars in
the primary dentition, the primary molars are replaced by permanent
premolars. |
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If any primary teeth are lost before permanent teeth are ready to
replace them, some posterior teeth may drift forward and cause space to
be lost in the mouth. |
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This may cause crowding and/or misplacement once the permanent teeth
erupt, which is usually referred to as
malocclusion. |
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Qualified Community Specialists
(Orthodontist) may be required in such circumstances for
children
to achieve a straight set of teeth ("Braces"). |
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Permanent Teeth
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The permanent dentition (32
permanent teeth) begins when the last primary or baby tooth is lost,
usually at 11 to 12 years, and lasts for the rest of a person's life or
until all of the teeth are lost (edentulism). |
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During this stage, third molars
(also called "Wisdom
Tooth") are frequently
extracted
because of decay, pain or impactions. |
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The main reasons for tooth loss
are Tooth Decay
or Gum Disease. |
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SOME USEFUL TIPS on the PRIMARY TEETH DEVELOPING
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- For every 6 months of life, approximately 4 teeth will erupt
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- Lower teeth usually erupt before upper teeth
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- The teeth in both jaws usually erupt in pairs – one on the right
and one on the left
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- Primary teeth are smaller and
whiter than the permanent teeth
that will follow
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- Girls generally go before boys in tooth eruption
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- By the time a child is 2 to 3 years of age, all primary teeth
should have erupted
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- Shortly after age 4, the jaw of the child begins to grow,
creating spaces between the primary teeth
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- That provides the necessary space for the larger permanent teeth
to erupt
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- Between the ages of 6 and 12, a mixture of both primary teeth
and permanent teeth exist in the mouth
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More details... |
Contact Dentist |
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Looking forward to hearing from
you Aleksandr
V. Melekhin, DDS |
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Return from Dentition to Philadelphia
Dentist |
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