4. oral cavity - teeth Flashcards
What is meant by heterodont?
tooth shape differences along the tooth row- I, C, PM, M
What is meant by diphyodont?
any animal with two successive sets of teeth, initially the “deciduous” set and consecutively the “permanent” set
what is meant by homodont?
have all the same types of teeth, performing the same function
What is meant by diastema?
a physiological gap between the incisors and the premolars
name the main anatomy structures of a tooth
- Cementoenamel junction (CEJ)
- Alveolus bone socket (alveloli)
- Lamina dura
- periodontium (membrane)
- periodontal ligaments
- Pulp cavity
- dentin
- enamel
- cementum
where is the cementoenamel junction (CEJ)?
the borderline between the crown and root(s)
what is the Alveolus bone socket (alveloli)?
it anchors the tooth by its root into the socket
what is the lamina dura?
the thin shell of dense bone lining the alveoli
what is the pulp cavity?
It is the central space of the tooth containing pulp- soft tissue with nerves, vessels, lymphatics
what is periodontium and what does it do?
it is a connective tissue that attaches the root to the bone via periodontal ligaments
what 4 structures are included in periodontal tissues?
gingiva,
cementum,
alveolar bone,
periodontal ligament
name the hard tissues in the teeth?
enamel
dentin
cementum
what do cells in the gums adhere to at the gingival crevice/ sulcus
cells of the enamel adhere via a basement membrane
what is meant by gums/gingiva?
oral mucosa that covers the tooth
Name the 2 teeth types
brachydont
hypsodont
Describe brachydont teeth
Smaller and low crowned suitable for feeding on soft diet, it has a true root
describe hypsodont teeth
- Larger crowned teeth that can resist the wear and tear of feeding on a tough and fibrous diet as in ungulates
- Radicular: forms true root or aradicular root: no true root
Aradicular hypsodont:
teeth with a long anatomic crown, erupt continuously and while errupting, remain open rooted
what is enamel and what cell type is formed from
hardest substance in the body, formed from ameoblast
in brachydont teeth what does the enamel cover?
only the crown
in hypsodont teeth what does the enamel cover?
covers the entire body of the tooth, but not the root
what is dentin and what cell type is it formed from?
the hard substance which forms the bulk of the tooth and surrounds the pulp cavity.
Formed by odontoblasts
what us cementum and what does it cover in brachydont and hypsodont teeth?
thin bonelike layer
- brachydont: covers root only
- hypsodont: fills infundibula and covers entire tooth
what are the 4 types of teeth?
incisors
canines
premolars
molars
What Is the function of incisors?
adapted for grasping, pinching, scratching and nipping
What Is the function of canines?
“weapons” for tearing flesh during hunting & fighting
what is the function of premolars?
rostral cheek teeth which have deciduous precursors; molars do not. Shearing off food
what is the function of molars?
flattened and triangular with jagged edges; function like serrated-edged blades. Shearing and grinding food.
describe the vestibular surface of the tooth
Surface of the tooth facing the vestibule or lips (buccal and labial)
describe the lingual surface of the tooth
Surface of the maxillary or mandibular tooth that faces the tongue or median plane of the mouth, and the caudal surfaces of the C, PM or M
describe the palatal surface of the tooth
refers to the lingual surface of the maxillary teeth
describe the coronal surface of the tooth
is used as a term relating toward the occlusal surface
describe the medial surface of the tooth
Surfaces of the incisor teeth that are toward the middle or median plane of the mouth. Rostral surface of the canine, premolar and molar teeth
describe the distal surface of the tooth
Surface of the incisor teeth that are away from the middle or median plane of the mouth. Caudal surfaces of the canine, premolar and molar teeth
How many permanent teeth do pigs have? how many deciduous teeth do they have?
permanent- 44
deciduous- 28
what is the dental formula for pigs permanent and deciduous teeth?
permanent
I-3 C-1 P-4 M-3
I-3 C-1 P-4 M-3
deciduous
I- 3 C-1 P-3
I- 3 C-1 P-3
how many teeth do dogs have?
42
which tooth are dogs missing?
upper M3
which teeth are carnassial in dogs?
upper PM4
lower M1
what is the dental formula of dog teeth?
I- 3 C-1 P-4 M-2
I-3 C-1 P-4 M-3
describe the roots of dog teeth
- All incisors have a single root
-The root of the canine is large; larger than the crown - PM1s have a single root
- PMs and Ms have two roots:
-Exception: Upper PM4 and the two upper molars have three roots - Exception: Lower M3 has one root
describe ruminant teeth?
-Dental pad, no upper incisors or canines
- Incisors and canines are brachydont
-Premolars and molars are hypsodont
- large diastema
-32 teeth
how many teeth do horses have?
40 or 42 depending on whether they have vestigial world teeth
describe horse teeth
- Slowly errupt
- Hypsodont crowned teeth have continuous wear
- Delayed development of roots
- Complicated folding of enamel: infundibulum
- Brachydont & in diastema
- Incisors: High crowns with single root
- Pre/molars form continuous surface
- PM2-PM4 and M1-M3 three roots in the upper jaw and two in the lower jaw
what is meant by infundibulum
- An infundibulum is a cup or funnel-shaped invagination of enamel from the occlusal surface of equine incisor and maxillary cheek teeth
- Looks like a dark mark, because food gets packed inside and turns black as it decays
- Partly filled with cement, leaving small cavity but does not connect with the pulp cavity
- As the tooth continually erupts and wears down the appearance of the occlusal surface changes
secondary dentin forms dental stars on worn surface of tooth - Wear of the occlusal surface causes the cup to get smaller and eventually disappear from all lower incisors (at about 8 years of age) leaving the enamel spot in its place
describe lagamorph teeth
- 2 small incisors (peg teeth) behind maxillary incisors
- 3 pairs of incisors: 2 upper, 1 lower
- enamel thicker on the facial aspect, thinner on lingual
- both incisors and cheek teeth are radicular hypsodont (long anatomic crown, erupt continuously and remain open rooted)
- no canine teeth
- have horizontal occlusion surface - transverse enamel folds for shredding & grinding tough fibrous food
Describe the blood supply to teeth
- upper teeth: infraorbital artery
- lower teeth: inferior alveolar artery (IAA)
describe the nerve supply to teeth
- trigeminal nerve supplies sensory innervation through its maxillary and mandibular division
- upper incisor teeth innervated by the infraorbital nerve
- mandibular teeth are innervated by inferioralveolar nerve
which canal does the infraorbital nerve run in?
infraorbital canal
which canal does the inferioralveolar nerve run in?
mandibular canal
