55 terms

Oral Bio -Unit 4 The Tooth Functions and Terms

6 Functions of the teeth
1. protection of oral cavity
2. mastication
3. speech/communication
4. esthetics
5. tools/weapons
6. aid in digestion
area where crown and root meet
Cementoenamel junction CEJ
actual crown and actual root; never depends on eruption; never changes other than through attrition or other physical wear
Anatomical crown/root
what is seen clinically; the protion of the crown and or root that is visible and not covered by gingiva
Clinical crown/root
portion of jaw that supports teeth; resorbs when teeth are extracted
Alveolar process
a socket which holds individual teeth
teeth in the upper jaw
Maxillary teeth
teeth in the lower jaw
Mandibular teeth
What are the 4 tissues making up teeth
1. Enamel
2. Dentin
3. Cementum
4. Pulp
hardest tissue in the body
Makeup of Enamel
96% mineralized or inorganic
1% organic
3% water
natural wearing away of teeth by tooth to tooth contact such as grinding the teeth
enamel lost by chemical means and what are they
-acid content of vomit
-overuse of acid containing
-acidic foods
makes up the bulk of tooth; hard and calcified; can repair itself
Makeup of Dentin
70% mineralized or inorganic
20% organic
10% water
dentin deposited before completion of apical foramen
Primary dentin
Secondary dentin
-lies between pulp chamber and primary dentin
-formed after completion of apical foramen
-more calcified than primary dentin
-forms at a slower rate than primary dentin
continues to form throughout the life of the tooth
-provides protection to pulp horns; reduces overall pulp chamber
formed in response to trauma; located directly beneath trauma; cavity preparation, decay, occlusal stress
reparative dentin
-bone like substance covering tooth's root
-main function:provides attachment medium for tooth to the alveolar bone
-thin at CEJ
thicker at apex
Makeup of Cementum
45-50% mineralized inorgagic
50-55% organic
trace amounts of water
primary; covers the whole root; formed at a slow rate
Acellular cementum
secondary; only at apical 1/3; can reproduce itself and compensate for occlusal wear (attrition) formed at a faster rate
Cellular cementum
Junction of enamel patterns
60-65% of all teeth overlap - cementum overlaps a small part of the enamel
30% of all teeth meet - cementum meets enamel edge to edge
5-10% of all teeth gap - cementum and enamel do not meet; exposes dentin; adds to probability of sensitivity
supply WBC's to fight bacterial invasion and nourishment to activate and support the formation of secondary dentin
Blood vessels
filter fluids in the pulp
lymph vessels
support system for the structures in the pulp
connective tissue
respond to pain in the pulp
nerve tissue
dentin forming cells
lined with odontoblasts
Function of pulp
provide nourishment; sensory properties; supports the reparative system of dentin
What 5 things does the pulp consist of?
1. blood vessel
2. lymph vessels
3. connective tissue
4. nerve tissue
5. lined with odontoblasts
located in the coronal portion of the tooth
pulp chamber/coronal pulp
located in the radicular portion of the tooth
pulp canals/root canals
extensions of coronal pulp into cusps of posterior teeth
pulp horns
3 basic food precession functions
1. cutting
2. holding/grasping
3. grinding
function of teeth determined by 3 things
1. size
2. shape
3. location in dental arch
function of incisors
shovel shape aid in guiding food into the mouth
function of canines
-hold or grasp, used as weapon or tool
-longest roots
-strong anchor at the corner of the mouth due to the wedge shape in cross-section
function of Premolars
cross between canine and molar; hold and grind
function of molars
chew and grind, designed to interlock or intercuspate with opposing arch
surfaces next to each other in the same arch
proximal surfaces
all developmental growth centers of tooth
lines denoting where fusion of the lobes took place
developmental grooves
small elevation of extra enamel on the crown
depression on concavity on the tooth, location determines name
lingual lob of an anterior tooth
a pinpoint depression; location determines name
mound on crown that makes up major division of occlusal or incisal surface
small rounded projections of enamel on incisal edge of newly erupted teeth
rounded linear elevation on a surface of a tooth
rounded linear elevation of enamel that form mesial or distal borders of occlusal surfaces on posterior teeth and mesial and distal boarders on lingual of anterior teeth
marginal ridge
carved out or indented area
opposite of concave; bulging out
ridge that descends from the tips of the cusps of molars and premolars toward the central part of the occlusal surface
triangular ridge
the union of two triangular ridges
transverse ridges
secondary grooves other than the main dividing lines
supplemental grooves