Basic oral anatomy

oral anatomy

1. BASIC ORAL BASIC ORAL
ANATOMYANATOMY

2. Oral Cavity (Oral Cavity (mouth)mouth)
The entire oral cavity is lined with mucous The entire oral cavity is lined with mucous
membrane tissue. The oral cavity consists membrane tissue. The oral cavity consists
of the following two areas: of the following two areas:
The The vestibule vestibule is the space between the is the space between the
teeth and the inner mucosal lining of the teeth and the inner mucosal lining of the
lips and checks.lips and checks.
The The oral cavity proper oral cavity proper is the space is the space
contained within the upper and lower contained within the upper and lower
dental arches.dental arches.

3. The DentitionsThe Dentitions
The term The term dentitiondentition is used to describe the natural is used to describe the natural
teeth in the jawbones.teeth in the jawbones.
Primary dentitionPrimary dentition is the first set of 20 primary is the first set of 20 primary
teeth. Also referred to as “baby teeth” or teeth. Also referred to as “baby teeth” or
“deciduous teeth”“deciduous teeth”
Permanent dentitionPermanent dentition refers to the 32 secondary refers to the 32 secondary
or “adult” teeth.or “adult” teeth.
Mixed dentitionMixed dentition occurs when both primary and occurs when both primary and
permanent teeth are present, usually between the permanent teeth are present, usually between the
ages of 6 to 12.ages of 6 to 12.

4. Dental archesDental arches
The The maxillary arch maxillary arch (upper arch), (upper arch), actually actually
part of the skull, is fixed and not capable of part of the skull, is fixed and not capable of
movement. The teeth in the upper arch are movement. The teeth in the upper arch are
set in the maxilla, the maxillary bone.set in the maxilla, the maxillary bone.
The The mandibular arch mandibular arch (lower arch) (lower arch) is is
capable of movement through the action of capable of movement through the action of
the temporomandibular joint. The mandible, the temporomandibular joint. The mandible,
the mandibular bone supports the teeth in the mandibular bone supports the teeth in
the lower arch.the lower arch.

5. QuadrantsQuadrants
An imaginary An imaginary midline midline divides each arch divides each arch
into a left half and a right half. When the into a left half and a right half. When the
maxillary and mandibular arches are each maxillary and mandibular arches are each
divided into halves the resulting four divided into halves the resulting four
sections are called sections are called quadrants, quadrants, as follows:as follows:
2.2.Maxillary right quadrantMaxillary right quadrant
3.3.Maxillary left quadrantMaxillary left quadrant
4.4.Mandibular right quadrantMandibular right quadrant
5.5.Mandibular left quadrantMandibular left quadrant

6. Directions of the Oral CavityDirections of the Oral Cavity
Anterior Anterior means toward the front of the means toward the front of the
mouth.mouth.
Posterior Posterior means toward the back of the means toward the back of the
mouth.mouth.
Medial Medial means toward the middle or toward means toward the middle or toward
the middle of the arch.the middle of the arch.
Lateral Lateral means toward the side or toward the means toward the side or toward the
outside of the mouth.outside of the mouth.

7. Mesial Mesial means toward the mid-line of the means toward the mid-line of the
dental arch.dental arch.
Distal Distal means away from the mid-line of the means away from the mid-line of the
dental arch.dental arch.

8. Eruption & ExfoliationEruption & Exfoliation
Eruption Eruption is the movement of the tooth is the movement of the tooth
through the surrounding tissues so that through the surrounding tissues so that
more of the tooth becomes visible in the more of the tooth becomes visible in the
mouth.mouth.
ExfoliationExfoliation is the process by which the roots is the process by which the roots
of the baby tooth are resorbed and of the baby tooth are resorbed and
dissolved until so little root remains that the dissolved until so little root remains that the
baby tooth falls out.baby tooth falls out.

9. OcclusionOcclusion
Occlusion Occlusion is the relationship of the is the relationship of the
mandibular and maxillary teeth when closed mandibular and maxillary teeth when closed
or during excursive movements of the or during excursive movements of the
mandible; when the teeth of the mandibular mandible; when the teeth of the mandibular
arch come into contact with the teeth of the arch come into contact with the teeth of the
maxillary arch in any functional relationship.maxillary arch in any functional relationship.

10. Types of TeethTypes of Teeth
The functions of teeth vary, depending on their The functions of teeth vary, depending on their
individual shape and size and their location in the individual shape and size and their location in the
jaws. The three basic food processing functions of jaws. The three basic food processing functions of
the teeth are cutting, holding or grasping, and the teeth are cutting, holding or grasping, and
grinding.grinding.
Incisors Incisors are single-rooted teeth with a relatively are single-rooted teeth with a relatively
sharp thin edge referred to as the sharp thin edge referred to as the incisal edge.incisal edge.
Located in the front of the mouth, they are Located in the front of the mouth, they are
designed to cut food without the application of designed to cut food without the application of
heavy forces. heavy forces. Central Central (front teeth) and(front teeth) and lateral lateral
(distal to the centrals) teeth are incisors.(distal to the centrals) teeth are incisors.

11. Canines, Canines, also known as also known as cuspids,cuspids, are located at are located at
the corner of the arch. They are designed for the corner of the arch. They are designed for
cutting and tearing foods, which require the cutting and tearing foods, which require the
application of force.application of force.
Premolars Premolars are a cross between canines and are a cross between canines and
molars. An older term for premolar is molars. An older term for premolar is bicuspid. bicuspid.
The pointed cusps hold and grind the food. They The pointed cusps hold and grind the food. They
have a broader surface for chewing food. There have a broader surface for chewing food. There
are two sets of premolars in the permanent are two sets of premolars in the permanent
dentition and dentition and NO NO premolars in the primary premolars in the primary
dentition. dentition.

12. Molars Molars are much larger than premolars. are much larger than premolars.
The molars have more cusps than other The molars have more cusps than other
teeth that are used to chew or grind up food. teeth that are used to chew or grind up food.
There are two sets of molars in the primary There are two sets of molars in the primary
dentition and three sets of molars in the dentition and three sets of molars in the
permanent dentition.permanent dentition.

13. In each quadrant there are five permanent In each quadrant there are five permanent
teeth (central, lateral, canine, & premolars) teeth (central, lateral, canine, & premolars)
that succeed or take the place of the five that succeed or take the place of the five
primary teeth (central, lateral, canine, & primary teeth (central, lateral, canine, &
molars), they are called molars), they are called succedaneoussuccedaneous
teeth. Three permanent molars do not teeth. Three permanent molars do not
succeed primary teeth in each quadrant; succeed primary teeth in each quadrant;
therefore they are therefore they are nonsuccedaneous nonsuccedaneous teeth.teeth.

14. KeywordsKeywords
DentitionDentition
OcclusionOcclusion
Maxilla - maxillaryMaxilla - maxillary
Mandible –mandibularMandible –mandibular
MidlineMidline
QuadrantQuadrant
AnteriorAnterior
PosteriorPosterior
MedialMedial
Lateral (direction)Lateral (direction)
Permanent – adultPermanent – adult
Oral cavityOral cavity
IncisorIncisor
CentralCentral
LateralLateral
Canine - cuspidCanine - cuspid
Premolar – bicuspidPremolar – bicuspid
MolarMolar
SuccedaneousSuccedaneous
EruptionEruption
ExfoliationExfoliation
Primary – deciduous – Primary – deciduous –
babybaby
VestibuleVestibule