Oral Anatomy and Histology Flashcards
ENAMEL
a hard protective tissue that covers the crown of the tooth.
* Location is the outer surface of the anatomical
crown
* Thickest at the tip of the crown and thinner at
cervical portion
* Color varies with thickness (Yellow-white or gray-
white)
* Hardest tooth tissue
* It is smooth (self-cleansing)
DENTIN
makes up the main bulk of the tooth. Dentin is
found in both the crown and root of the tooth.
* Main portion or body of the tooth
* Present in both the root and the crown
* Softer than enamel, harder than cementum or
bone
* Can continue to form throughout the lifespan of a
tooth
CEMENTUM
covers the root of the tooth
* Covers the root of the tooth
* Attaches the tooth to the bone
* Softer than enamel or dentin
* Light yellow in colour
PULP
soft connective tissue containing nerves and
blood vessels - in the center of the tooth.
* Center of the tooth, surrounded by dentin
* Nourishing and sensory (pain) function
* Composed of blood vessels, lymph vessels,
connective tissues, and nerve tissue
* Two parts of the pulp cavity
◦ pulp chamber and
◦ pulp canal
* The pulp horn is the extension of the chamber
Common Structures of a Tooth
-
Crown: the white part of tooth, covered with
enamel -
CEJ: the crown and root are joined at the
cemento-enamel junction (neck of tooth)
◦ The CEJ is also called the cervical line or the
cervix
*Root: part of the tooth covered in cementum,
embedded in the bone -
Apex: terminal end of the root.
◦ Apical foramen: tiny opening in the apex of the
root for blood vessels and nerves to enter
The Tooth Root
- All teeth have at least one and often more than
one root. - The root is covered by cementum and embedded
in the alveolar process. - Between the bone of the alveolar process and the cementum is the periodontal ligament, which
suspends the tooth and provides it with
nourishment. - Remember…the end of the root is called its apex;
the hole in the apex through which blood and
lymph vessels and nerves pass is called the apical
foramen - The term apical is used to describe something that has to do with the apex.
What’s the opposite of apical?
Structures associated with the tooth’s crown are
termed coronal.
Radicular
◦ having to do with the tooth root.
◦ the radicular pulp is the pulp contained in the
root
What teeth have a single root?
These are found in the anterior teeth and a few posterior teeth
Bifurcated Root
These divide into two seperate parts
This root is typically found on lower molars
Trifurcated Roots
- Means the division of a root into three separate parts
- This provides the tooth with maximum anchorage against biting force
- Typically upper molars where anchorage is essential
Incisors
- There are four incisors in each arch. Two central
incisors and two lateral incisors. - Location – the central incisors are side by side at
the midline. There is a lateral incisor on each side
of the central incisors. - Shape – single rooted, crowns are arched and
angle toward one sharp incisal edge. - Function – to cut or incise food with their thin
edges. Tongue side is shovel shaped
Cuspids (Canines)
- There are two cuspids in each arch. They are
sometimes referred to as canines. - Location – next to the lateral incisors, establishes
the corner of the arches. - Shape – anchored with the longest root, one
pointed cusp. - Function – used for holding, grasping, and tearing
food. Referred to as the cornerstone of the mouth
Premolars (bicuspids)
- There are four premolars in each arch. Two first
premolars and two second premolars. They are
sometimes referred to as bicuspids. - Location – first premolars are next to the cuspids
followed by the second premolars. - Shape – maxillary first premolars have a bifurcated root, all others have one root, one prominent cusp with one or two lesser lingual cusps.
- Function – holding food, like canines because they have cusps; also to grind food
Molars
- There are six molars in each arch (3 in each
quadrant) of the permanent dentition. Two first
molars, two second molars and two third
molars. Third molars are sometimes called
wisdom teeth. - Location – first molars are next to the second
premolars, second molars next to the first molars
and third molars next to the second molars. The
third molars are the farthest teeth in the mouth. - Shape – bifurcated or trifurcated roots, broad
chewing surfaces with four to five cusps. - Function – grinding or chewing food
Tooth Surfaces
- Occlusal surfaces: posterior teeth
- Incisal surfaces: anterior teeth
- Lingual surfaces (Palatal Maxillary Teeth)
- Facial surfaces
◦ Buccal
◦ Labial - Proximal surfaces
◦ Mesial surfaces
◦ Distal surfaces - Interproximal area: space between the teeth
What are the two front teeth on the maxillary arch known as?
Central Inciisor
How many premolars are in an adult dentition?
8
(2 per quadrent)
Which molar is next to the premolars?
First molar
