Oral Structures and Types of
teeth
By:
Ms. Zain Malkawi, MSDH
Introduction
• Oral structures are
essential in reflecting local
and systemic health
• Oral anatomy: a
fundamental of dental
sciences on which the oral
health care provider is
based.
• Oral anatomy used to
assess the relationship of
teeth, both within and
between the arches
The color and morphology of the structures may
vary with genetic patterns and age.
One Quadrant at the Dental Arches
Parts of a Tooth
• Crown
• Root
Parts of a Tooth
• Crown: part of the tooth
covered by enamel,
portion of the tooth visible
in the oral cavity.
• Root: part of the tooth
which covered by
cementum.
• Posterior teeth • Anterior teeth
Root
• Apex: rounded end of the
root
• Periapex (periapical): area
around the apex of a tooth
• Foramen: opening at the
apex through which blood
vessels and nerves enters
• Furcation: area of a two or
three rooted tooth where
the root divides
Tooth Layers
• Enamel: the hardest calcified
tissue covering the dentine in
the crown of the tooth (96%)
mineralized.
• Dentine: hard calcified tissue
surrounding the pulp and
underlying the enamel and
cementum. Makes up the
bulk of the tooth, (70%)
mineralized.
Tooth Layers
• Pulp: the innermost
noncalsified tissues
containing blood
vessels, lymphatics
and nerves
• Cementum: bone like
calcified tissue
covering the dentin in
the root of the tooth,
50% mineralized.
Tooth Layers
Tooth Surfaces
• Facial: Labial , Buccal
• Lingual: called palatal
for upper arch.
• Proximal: mesial , distal
• Contact area: area
where that touches the
adjacent tooth in the
same arch.
Tooth Surfaces
• Incisal: surface of an incisor which toward the
opposite arch, the biting surface, the newly
erupted “permanent incisors have mamelons”:
projections of enamel on this surface.
• Occlusal: surface of posterior teeth that is
toward the opposite arch, the chewing surface.
Tooth Sides
One Quadrant at the Dental Arches
Types of Teeth
• Primary Teeth (Deciduous Teeth)
• Permanent Teeth (Adult Teeth)
The Primary Dentition
• Primary dentition (decidous) consists of 20
teeth, 8 incisors, 4 canines, and 8 molars.
Primary Teeth (Dental arch)
The Primary Dentition
• The anatomy of the primary teeth is similar to
that of permanent teeth except :
primary teeth are smaller in size
They are whiter
The crowns are shorter
The occlusal table is narrower faciolingually
Pulp chambers are larger
Roots are longer and slender
Root Trunk: area from the cementoenamel junction to
the furcation are shorter
Have fewer anomalies and variations in tooth form
Permanent Dentition
• Consists of 8 incisors, 4 canines, 8 premolars and
12 molars
• Teeth have one, two, or three roots
