Lecture 11: Head & Neck Digestive Pathway (Exam 2) Flashcards
Describe the lips
- Sensitive & mobile
- Used for selection & prehension of food
- Upper lip sensitivity is used when a twitch is applied (releases endorphins)
Describe the oral vestibule
- Communicates w/ the oral cavity by the diastema & the space caudal to the last molar
- Btw/ the teeth & lips (or cheek)
Define the palatoglossal arch
- Caudal boundary joins caudal end of the hard palate & the root of the tongue
Describe the hard palate
- Dorsal boundary
- Incisive, maxillary, & palatine bones covered w/ a thick mucosa w/ uneven palatine crests (3), enlarged palatine venous plexus (2), & incisive papilla (1)
What does it mean that the incisive papilla is blind
Phermones don’t enter through it just the nose
Describe the tongue
- Ventral boundary
- Same parts as carnivores
- Long spatulate in its apex w/ a narrow frenulum (1) w/ two ventral fleshy caruncle (2)
What kind of surface does filiform papillae give
Velvet like surface
T/F: Fungiform papillae are scarce
True
How many vallate papillae are found btw/ the body & the root of the tongue
2 big vallate papillae
Where are the foliate papillae found
Lateral in the root
What is a difference in the oropharynx in equine
- The soft palate is very elongated
- Large palatine tonsils w/ no covering
What are the boundaries of the oropharynx
- Soft palate - dorsal boundary
- Palatoglossal arch - rostral artery
Where are glossoepiglottic folds located
Btw/ the root of the tongue & the base of the epiglottis
What is located on each side of the glossoepiglottic folds & leads to the laryngopharynx (piriform recesses)
- Epiglottic vallecula
- Help prevent food from coming into the airway
Label the following:
What is a difference of the laryngopharynx in equine
Lacks the pharyngo-esophageal limen (fold)
What is the job of equine teeth
To cut, crush, & grind highly fibrous feed stuff
Define brachydont teeth
Very short teeth found in carnivores
What type of teeth do herbivores have (equine)
Hyposodont (long tooth)
What is the clinical crown
The part of the tooth you can see
What is the reserved grown
The part of the tooth inside the bone
How much wear occurs in equine teeth a year
2 - 3 mm per year
Label the following:
Describe cementum
- Covers surface of teeth
- Forms periodontal ligament
- Stains easily
What does the periodontal ligament
- formed by cementum that cements the tooth into the alveolar bone
Label the following:
Describe enamels
- A layer under the cement
- Incisors have a second involution of enamel creating a a “cup” (or infundibulum)
Describe Dentin
- Living softer layer deep to the enamels
What continues to produce new (secondary) dentin throughout lifie
Odontoblasts
What is the dental star
Secondary dentin fills in the exposed pulp cavity as the tooth is worn down
Label the following:
What types of teeth are found in equine
- Incisors
- Canines (sometimes not in mares)
- Premolars
- Molars
What is the first upper premolar called (describe it)
- Wolf tooth
- May or may not be present
- Small & nonocclusal
What is the formula for deciduous teeth in equine
What is the formula for permanent teeth for equine
What are the names of the the incisiors
- Central
- Intermediate
- Corner
Label the following: (A is upper jaw & B is lower jaw)
What are considered “cheek teeth”
All molars & premolars (except the wolf tooth)
What is the first cheek tooth
2nd premolar
Describe the rule of four & nine system in equine
- Tooth X04 is always the canine
- Tooth X09 is always the first molar
- Tooth X06 is the first cheek tooth
Label the following:
What does anisognathus mean
The upper arcade is wider while the narrow arcade is narrow (red line see in pic)
What is a result of anisognathus
- Uneven wear of occlusal surface
- Points on the buccal side of the upper cheek teeth & lingual side of the lower cheek teeth
T/F:: The upper arcade tends to have teeth further dorsal than the lower arcade
F; further rostral
What causes the formation of hooks
- uneven wear on the first upper cheek tooth & last lower cheek tooth
- b/c of the further rostral teeth found in the upper arcade
What can prevent hooks & point formation & improve the grinding surface
Floating
Label the strokes found in a healthy equine chewing motion
Describe the most accurate eruption dates when using teeth to ages
- For incisors
- Central incisors erupt @ 6 D
- Interm - erupt 6 W
- Corner - erupt 6 M
- Central - changes to permanent @ 2.5 Y
- Interm - permanent 3.5 Y
- Corner - permanent @ 4.5 Y
Describe in wear
Takes up to 6 M for teeth to erupt to occlusal surface & for enamel to begin to erode
What is “level”
All enamel is in wear
When do cups begin to disappear
- Around 6 Years of age
- Dental star is black spot while infundibulum is lighter/yellow spot
What is the eruption of canines
5 Y
What is the eruption of the pre molar teeth
- 2
- 3
- 4
When do molars erupt
- 1
- 2
- 3.5 - 4
- Eruption bump on lower jaw
Label the following:
- 1: Cup (black cavity in center of infundibulum)
- 1’: Enamel spot (Proximal end of infundibulum)
- 2: Dental cavity
- 3: Dental star (changing in shape from a linear to a rounded form)
- 4: Outer & inner enamel rings
What are some other things to consider (length v. width of upper corner incisor)
- 5 to 9 Y: tooth is wider than it is tall
- 9 to 10 Y: shape is square (width=height)
- > 10 Y: tooth continues to get taller w/ age (height > width)
What is there to consider about the angle @ which the incisors meet
- The upper & lower incisors in young horses meet at a fairly upright angle (~180 degrees)
- As the horse ages the incisors meet @ a more acute angle (< 120 degrees)
What needs to be considered about the upper corner incisor hook
- Appears @ 7 years & again @ 11 years
- Not very reliable
What is there to consider about the galvayne’s groove
- Groove in upper corner incisor
- Appears @ 10 Y
- Half way down @ 15
- All the way down the tooth @ 20 Y
- Halfway gone @ 25 Y
- All the way gone @ 30 Y
The length of the reserve crown (increases/decreases) w/ age after completing formation around 5 years of age
Decreases
The relationship of the teeth w/ the sinuses (stay constant/change) as the horse ages & teeth are worn
Change
What teeth’s roots are w/in the rostral maxillary sinus & which are w/in the caudal maxillary sinus in adult horses
- PM4/M1 - rostral maxillary sinus
- M2/M3 - caudal maxillary sinus
