Deep Head (Teeth, Tongue, TMJ) Flashcards
CN responsible for motor innervation to muscles of the rostral 2/3rds of the tongue
CN V3: trigeminal - mandibular nerve
CN responsible for sensory innervation to tastebuds of the rostral 2/3rds of the tongue
CN 7: facial nerve
what nerve provides innervation to the muscles of the caudal 1/3 of the tongue (motor)
CN XII: hypoglossal nerve
what nerve provides sensory innervation of tastebuds to the caudal 1/3 of the tongue
CN IX (9): glossopharyngeal nerve
what spaces does the tongue occupy
occupies much of the oral cavity, some of the oropharynx
Describe follate papillae in ruminants
absent
are filiform papillae mechanical or sensory
mechanical
are fungiform papillae sensory or mechanical
sensory (taste)
what are the 3 kinds of sensory papillae that make up the taste buds
fungiform, follate, vallate
which two papillae are scattered all over the tongue
fungiform and filiform
lentiform papillae are modified ______ papillae
filiform
where are vallate papillae mostly found
towards the base of the tongue
where are foliate papillae typically found
on lateral surface, caudal aspect of tongue
describe conical papillae
caudally oriented, filiform papillae
clinical significance of the lingual fossa
can collect food but becomes easily infected
which species have a lingual fossa
Ox and sheep
which species do not have a lingual fossa
dogs, cat, pig, horse
The extrinsic muscles of the tongue connect it to _____
bone
The styloglossus muscle connects the tongue to the ______
Stylohyoid bone
which muscle elevates the tongue
mylohyoideus
T/F: the mylohyoideus muscle is an extrinsic muscle of the tongue
F: technically not an extrinsic muscle
name 3 tooth tissues
enamel, cementum, dentine
describe enamel
acellular - irreplaceable, one-time coating, present at eruption
hard - wears away with tooth wear
only on crown - erupted above gum line
describe cementum
softest - of the three tooth tissues
Cellular (like bone)
- covers root
describe dentine
- ivory
- lies deep to enamel
- cellular (like bone)
which tooth tissue has collagenous attachments that secure the tooth in alveolus
cementum
what is the only type of cell present in the pulp cavity
odontoblasts
role of odontoblasts
make dentine
what lines the inner layer of the pulp cavity
layer of odontoblasts which recede away from dentine as its made
what is contained within the pulp cavity
- contains CT
blood supply
innervation (pain)
crown
exposed part of the tooth
root
embedded part of tooth
neck
demarcation between the crown and the root
describe the location of the neck of the tooth
where enamel dives down below gum line/ where cementum overrides enamel
brachydont
low crowned - enamel part of tooth almost completely exposed with eruption (only a bit of reserved crown)
simple - not folded, no complex occlusal surface
Hypsodont
high crowned - enamel portion dives deep into gums, lots of crown in reserve, as tooth continues to erupt more crown will be exposed
complex - folded layers
what types of tooth tissue are exposed at the tooth surface in developed hypsodont teeth
enamel, dentine and cementum
in what kinds of species are hypsodont teeth common in?
herbivores
define diphydont
animal with two sets of teeth, initial deciduous (baby teeth) followed by permanent
define thecodont
teeth fixed in sockets/ alveolus in jaw –> most mammals
(can be brachydont or hypsodont tooth in socket)
what is the benefit of having 3 dental tissue types exposed
wear at different rates, good for grinding food
what is different about the roots in equine molars
teeth have multiple roots
what CN innervates the teeth
CN V –> trigeminal nerve (gives sensation of pain
define polyphydont
constant replacement of teeth (ex. sharks)
describe the path of the trigeminal nerve after it exits the maxillary foramen
after the trigeminal nerve exits the maxillary foramen, it becomes the maxillary branch of the trigeminal nerve will exit the infraorbital foramen to and give off fibers that innervate the upper incisors and canines
describe the path of the trigeminal nerve after it enters the maxillary foramen
trigeminal –> enters maxillary foramen –> become maxillary branch of trigeminal –> exits the infraorbital foramen –> gives off fibers that innervate upper incisors and canines
describe the path of the mandibular branch of the trigeminal nerve
mandibular branch of trigeminal enters mandibular foramen –> becomes inferior alveolar nerve –> gives off fibers that innervate lower teeth and and also exits mental foramen –> becomes mental nerve that innervate lower incisors and canines
incisors
adapted for cutting, embedding in the incisive bone or mandible
canines (cuspid) teeth are embedded….
at the junction of incisive and maxilla/mandible
describe premolars
teeth with deciduous precurssors, embedded in the maxilla/mandible
do molars have deciduous precursors
generally no, only erupt as permanent teeth
where are molars embedded
embedded in the maxilla/mandible
dog dental formula for deciduous teeth
313 (3 incisors, 1 canine, 3 premolars)
313 (3 incisors, 1 canine, 3 premolars)
describe the diastema in canine
caudal to canine teeth, rostral to premolar 4 –> premolars 1,2,3 do not touch
describe the diastema in the ox
between incisors and premolars
describe the difference in teeth in the upper vs lower jaw of the ox
upper jaw: no incisors, no canines
lower: incisors but no canines
dental formula of canine permanent teeth
3142 (3I, 1C, 4P, 2M)
3143 (3I, 1C, 4P, 3M)
describe how the dental quadrants are classified in the triadan system
first digit = quadrant of mouth
second and third digit = tooth placement
100 = upper right
200 = upper left
300 = lower left
400 = lower right
deciduous teeth:
500 = upper right
600 = upper left
700 = lower left
800 = lower right
describe wolf teeth in horses
vestigial premolar, inconsistently present , small and often removed
T/F: horses have multiple roots to their teeth
true!
describe tooth replacement in horses
deciduous teeth will still be in place as “caps”, some resorption of root will take place –> eventually fall out and permanent teeth migrate into place
do the upper and lower premolar articulate in dogs
no! where diastema is
what upper jaw tooth articulates with M1 of the lower jaw in canine
P4 - Carnassial tooth
what are M1 and M2 of the upper jaw in canine also classified as
bunodont/ crushing teeth, smooth edges
what ar P4 and M1 classified as in the lower jaw of canine
selodont/ cutting teeth, sharp edges
occlusal surface
contacts tooth in opposite jaw
mesial surface
“in between” surfaces of teeth, closer to midline
distal surface
in between surfaces of teeth farthest from midline
describe the teeth in a horse up to 4 years old
teeth are in wear, complex surface, “cups” are formed
describe teeth in a 5 year old horse
level, infundibulum is fully outlined (food can be packed into infundibulum cup)
describe teeth in 7 year old horses
cup is gone, no more cementum, still some infundibulum and tooth is becoming more angular
describe teeth in a 10 year old horse
round, enamel spot and dental star (secondary dentine), tooth more rounded and infundibulum completely gone
describe the teeth in a 17 year old horse
triangular, enamel spot gone, dental star is all that is left
at what age does incisor 3 erupt in a horse
4.5 years old
