Lecture 1 Flashcards
monophydont animals
rodents, dolphins
diphyodont
humans, cats, dog, cow, horse. have deciduous and permanent teeth
homodont
same type of teeth (shark, fish reptiles)
heterodont
teeth are different shapes: human, dog, cat
brachydont
short crown and long roots
dog, cat, human
hypsodont
long crown and short roots. continually erupt
two types of hypsodont teeth
radicular(closed true roots–have apex)–horse, cow cheek teeth
aradicular (rodent incisors, rabbits)
isognathous
equal jaws. occlusal surface aligned
anisognathous
unequal haws. mandible narrower than maxilla (dog, cat, cow, horse)
function of incisors
cut, scoop up, pick up,groom
canine function
pierce, hold, slash, tear
premolar function
hold, carry grind
dentigerous cyst
condition that occurs due to abnormal embryonic tooth development
embryonic tooth development
dental lamina. off of dental lamina there are invaginations where tooth bud starts to develop from. if have a secondary tooth, it also develops off of that lamina.
what does the dental sac form into
the structures that hold the tooth/support the tooth
what are the three stages of embryonic tooth development
bud
cap
bell
the sac around the enamel does what as the tooth erupts?
it opens, becomes part of the sulcus etc?
what happens if the dental sac doesn’t open into the oral cavity? what is this called?
it forms a dentigerous cyst (fluid production in sac that grows?). not painful but destroys tissues
apical (term)
root tip
coronal
crown area
cervical
neck area
rostral
towards nose
caudal
towards back
clinical crown
what is above the gum
anatomical crown
to the bottom of the sulcus?
attached gingiva
attached to bone. very important for tooth health
alveolar mucosa
loose unattached mucosa in the mouth
furcation
divisions (bi or tri)
apical delta
opening at the apex of the root. animals have multiple openings at the root tip (different than people)
pulp chamber
pulp in crown
pulp canal
pulp in the root
enamel features
made by ameloblasts most dense structure in the body--mostly inorganic thickest at the cusp of the tooth unable to regenerate subject to wear
attrition
tooth to tooth wear
dentin features
formed by odontoblasts from mesenchymal/dental papilla
continually produced
dentinal tubules if open to the outside–cause pain
regenerates
what are the three types of dentin
primary–pre-eruption
secondary–post-eruption, produced throughout life
tertiary/reparative–produced in response to trauma
what are the features of tertiary/reparative dentin?
unorganized
dense
decreased tubules
what are the structures in the pulp?
odontoblasts at edge. Root apexes with apical canals.
There may also be other pulp canals that open into tissue–e.g. in small dogs right at furcation of tooth. allows entry of bacteria more easily
what is the pulp comprised of?
blood/lymphatic vessels nerves fibroblasts odontoblasts undifferentiated mesenchymal cells--fewer stem cells as age
why is a young dog more likely to health a damaged tooth?
more pulp cavity--allows for swelling. more mesenchymal (undifferentiated cells) to help regrow
cementum features
what periodontal ligament fibers attach to
made by cementoblasts
begins at cementoenamel junction
gets thicker towards the apex of the tooth
At the neck of the tooth, cementum is acellular.
resorbed and repaired
cementum looks similar to what other tissue in the body
bone
what is hypercementosis?
when get extra cementum develop around the root. Can make a tooth impossible to take out completely unless take out the bone above it.
what is ankylosis?
the cementum is fused to the bone. Supposed to have fibers that attach tooth to the bone, rather than direct attachment. Very difficult to remove a tooth like that
what are periodontal ligament fibers?
they are fibers entrapped within cementum and alveolar bone
alveolar bone features
supportive resorbs and repairs also known as compact bone/cribriform plate/lamina dura (called this on x-ray) forms socket PDL fibers insert into it
what should be the distance between the cementoenamel junction and the alveolar margin?
less than 1 mm
periodontal ligament features
directed in different planes
BV, LV, nerves also present
What are the function ofs of periodontal ligaments?
shock absorption
attachment
protection
What is the most likely theory of tooth eruption?
as permanent tooth root forms, the permanent crown contacts the decciduous root and causes root resorption
Why can deciduous teeth be retained?
the permanent tooth absent
the permanent crown does not contact deciduous root
ankylosis–deciduous tooth
hormonal
masticatory mucosa
firmly attached to underlying tissues. para or keratinized SSE. most prone to stress and trauma: hard palate and attached gingiva
linning mucosa
has underlying CT that supports and allows movement
specialized mucosa
mouth
two types of gingiva
free and attached
when does attached gingiva get damaged?
in periodontal dz. can get gum recession or a pocket forming.
What is the gingival sulcus?
non keratinized, junctional epithelium that attaches gingiva to tooth. 0.5-2mm in dog, 0.5mm in cat
Frenula?
dogs have frenula between front teeth and two others?
dorsal papilla
very sensitive, quite large, sometimes mistaken as tumor
incisive ducts
pass through palatine fissures, to vomer-nasal organ
alveolar juga
can feel where roots of teeth are?
structures in the maxilla
caninenes, premolars, molars
alveolar juga
infraorbital foramen
lacrimal
How are the mandibles joined?
by a FIBROUS JOINT (not like human)
What is the mandibular canal?
a canal that runs along the bottom of the jaw. there are 3 mental foramen that are important for nerve blocks
What is the structure of the temoromandibular joint?
mandibular condyle and mandibular fossa of temporal bone that is 2 compartments separated by articular disc
What are the components of saliva?
serous and mucoid component
If the zygomatic is enlarged, what can you see?
bulging of eye?
In cats, what is the large “mass” in the mouth that is actually a salivary gland?
lingual and buccal molar–only in the cat
