exam 2: head and neck digestive pathway Flashcards
Sensitive and mobile, used for selection and prehension of food.
Lips
Upper lip sensitivity is used when a twitch is applied, releases ___________
endorphins
Communicates with the oral cavity by the
diastema and the space caudal to the last molar.
Oral vestibule
Caudal boundary of oral cavity, joins caudal end of
the hard palate and the root of
the tongue
Palatoglossal arch
Dorsal boundary of the oral cavity
Hard palate
what bones make up the hard palate? what is it covered by?
Incisive, maxillary and palatine bones, covered with a thick mucosa with uneven palatine crests(3) and an enlarged palatine venous plexus.
what is important to know about the incisive papilla in a horse compared to a dog
present but is blind in equines- pheromones only enter through the nose
Ventral boundary of the oral cavity
Tongue
Tongue: Long and spatulate in its _______, with a narrow ______ with two ventral fleshy ___________ caruncle .
apex, frenulum, sublingual
____________papillae gives a velvet-like surface to the tongue
Filiform
T/F Fungiform papillae are scarce on the tongue
true
___________ big vallate papillae between the body and the root of the tongue
2
where are the Foliate papillae located on the tongue
lateral in the root
narrow frenulum (1)
sublingual caruncle (2)
dorsal boundary of the oropharynx, it is elongated and has lymphoid tissue on it
soft palate
rostral boundary of the oropharynx
- Palatoglossal arch
what is located at the lateral walls of the oropharynx
large palatine tonsils (not covered like in dogs)
In the oropharynx, what is located between the root of the tongue and the base of the epiglottis
Glossoepiglottic fold
in the oropharynx, what structure is on each side of the fold, leads to the laryngopharynx (piriform recesses)
Epiglottic vallecula
purpose of the Epiglottic vallecula
prevents food from going into respiratory pathway
T/F the Laryngopharynx is located ventral to the larynx
false; dorsal
what doest the equine Laryngopharynx lack
Lacks Pharyngo-esophageal limen (fold)
what number on the diagram is the Laryngopharynx
6
Equine teeth needed to cut, crush, and grind what type of feed
highly fibrous feed stuffs
why type of teeth do horses (herbivores) have
Hypsodont – “long tooth”
How are the teeth of horses different from dogs/carnivores
horse= hypsodont (long)
dog= brachydont (short teeth)
T/F Teeth continue to erupt throughout life in a horse
true
equine teeth will “wear” how many mm
about 2-3 mm per year
what is the clinical crown of the tooth
part of the tooth you see when you open the mouth
what is the reserved crown of the tooth
the part of the tooth in the bone
what is the root of the tooth
tip of tooth in the bone
what is the Anatomical crown
the whole tooth
__________ covers surface of teeth and
forms periodontal ligament cementing
tooth in alveolar bone
- Cementum (stains easy)
what layer is under the Cementum layer of an equine tooth
Enamel
Incisors have a second involution of enamel
creating a “cup” called the __________
infundibulum
What is the layer under the enamel on the horse tooth
Dentin
what is significant about the dentin of the tooth
is a living, softer layer deep to the
enamel
what continue to produce new (secondary) dentin throughout life
Odontoblasts
Secondary dentin fills in exposed pulp
cavity as the tooth is worn down
what is this called
“dental star”
Types of Teeth for equine
- Incisor
- +/- Canines
- Premolars
- Molars
Do both sexes have canine teeth
- Found in both sexes but don’t tend to
erupt in mares.
what is the first premolar called
Wolf tooth
- Small and nonocclusal
- May or may not be
present
what is the common, overall term for premolars and molars
cheek teeth
T/F wolf teeth are called cheek teeth
NO
Deciduous dental formula
- 2(I3/3: C0/0: PM3/3) = 24
Permanent dental formula
- 2(I3/3 :C1/1 :PM4/3 :M3/3) = 36-42
How do we name the incisors in equine
central (1), intermediate (2), corner (3)
what is the first “cheek tooth”
2nd Premolar
Tooth X04 is always the _________ tooth
canine (104, 204, 304, 404)
Tooth X09 is always the _________
first molar (109, 209, 309, 409)
what tooth is X06
(2nd premolar) is the first cheek tooth of the horse
what does Anisognathus mean
teeth do not match perfectly (when they meet at point)
Upper arcade: (wider/ narrow)
Lower arcade: (wider/ narrow)
- Upper arcade: wider
- Lower arcade: narrow
Anisognathus (upper and lower arcades) result in
uneven wear of occlusal surface
uneven wear of occlusal surface of equine teeth leads to formation of
“Points” on buccal side of upper cheek teeth and lingual side of lower cheek teeth
Upper arcade tends to have teeth further ________ than lower arcade
rostral
Upper arcade tends to have teeth
further rostral than lower arcade
what does this lead to
Results in uneven wear and “hooks” on first upper cheek tooth and last lower cheek tooth
why do we float equine teeth
Regular “floating” can prevent hook and point
formation and improve the grinding surface
hook
what is the most accurate way to date horse teeth
Eruption Dates: most accurate
When do central, intermediate, corner incisors first erupt
6 days, 6 weeks, 6 months respectively
when do central, intermediate, corner incisors turn into permanent teeth
2.5, 3.5, 4.5 yrs
“In Wear” takes __________for teeth to erupt to occlusal surface and for enamel to begin to erode
6 months
what does “Level” mean when aging teeth
all enamel is in wear
how old
3 yrs
how old
2 yrs
- Cups begin to disappear around ________ of age
6 years
Eruption of canines and cheek teeth:
canines
5 years
Eruption of canines and cheek teeth
premolar and molar
premolar: 2, 3, 4
molar: 1, 2, 3.5-4
________ bumps or cysts are bony enlargements on the mandible or maxilla that occur during eruption of cheek teeth
Eruption
identify 1, 2,3
about how old is this horse:
tooth is wider than it is tall
5-9 yr
about how old is this horse:
shape is square (width = height)
9-10 yr
about how old is this horse:
tooth continues to get taller with age
(height > width)
> 10 yr
The upper and lower incisors in young horses meet at what angle
upright angle (~180°)
As the horse ages, the incisors meet at what angle
acute angle (<120°)
Upper corner incisor hook appears when?
Appears at 7 years and again at 11 years
- Not very reliable to use for aging
Galvayne’s Groove
when does the Galvayne’s Groove appear
10 years
Galvayne’s Groove is halfway down at ______yrs
15
Galvayne’s Groove is all the way down the tooth at _____
20
Galvayne’s Groove is all the way gone at
30 years
T/F The relationship of the teeth with the
sinuses change as the horse ages and
teeth are worn.
true
The length of reserve crown decreases
with age after completing formation
around _______________old
5 years of age.
what Pre molar and molar are in the rostral maxillary sinus
PM4/M1
what molars are in the caudal maxillary sinus
M2 /M3
how old is this horse
between 10-12 years
harder to know exactly the older they are
how old is this horse
4 years old
