Test 1 Flashcards
how many facial bones make our appearance?
14
functions of facial bones
respiration & digestion
name some large facial bones
mandible, 2 maxillae, 2 zygomatic bones
name some small bones
vomer, 2 palatine, 2 nasal, 2 lacrimal, 2 inferior nasal turbinates
2 bones that make the TMJ
temporal bone, mandible
name the muscles involved in mastication
masseter, temporalis, medial pterygoid and lateral pterygoid muscles
name the actions these muscle perform
elevate, depress, retrude, protrude
3 divisions of trigeminal nerve
ophthalmic, maxillary, mandibular
what does the ophthalmic do
sensory for upper 1/3 of face ( forehead, anterior scalp, eyeball, eyelid, nose)
what does maxillary do?
touch, pain, pressure, temperature of middle 1/3 of face and palate. Anterior superior alveolar n. for incisors and canines, middle superior alveolar n for premolars, posterior superior alveolar n is for molars.
what does mandibular nerve do?
sensory & motor. Touch, pain, pressure, and temperature for lower 1/3 of face, anterior 2/3 of tongue ( not taste), supplies 8 muscles of mastication plus the mylohyoid and anterior belly of digastric muscles which retract the mandible
how many muscles of mastication does the mandibular nerve control
8
what does facial nerve do?
sensory and motor, facial expression, salivary gland excretions of sublingual & submandibular glands. Sense and taste of anterior2/3 of tongue
What controls the posterior 1/3 of tongue?
glossopharyngeal nerve for taste and feeling as well as secretory stimulation for parotid glands, Hypoglossal n. if damaged deviates the tongue
name the 2 types of arches in the mouth
maxillary, mandibular
how are arches organized?
in quadrants ( upper left/ right…..)
state all directions and point to them on typodont
anterior/ posterior, mesial/distal, facial/lingual, buccal/ labial, occlusal/ incisal, apical/axial
more oreientation words
proximal, interproximal, gingival, coronal, interarch, intra-arch, radicular, interradicular
what is a line angle?
a line that two surfaces make when they meet. ( mesiobuccal line angle)
how are surfaces described?
1/3’s.
describing root 1/3’s
apical, middle, and cervical 3rd
describing surfaces
distal, middle, mesial 3rds
what is a contact?
where 2 teeth touch
what is an embrasure?
spaces near the point of contact.
what kind of embrasures are there
lingual, facial, gingival, occlusal, cervical, and incisal
another name for cervical embrasures
interproximal space
describe international counting system
quadrants 1-4 with a number 1-8 describing how far from the midline you go. (start upper right to left, then lower left to right)
primary dentition with international system
quadrants 5-8, with 1-5 following
using international system describe the mandibular left lateral insicer
32
describe the palmer system
use a half square describing quadrant followed by numbers 1-8 or for primary dentition a-e
describe the universal system
numbers 1-32 starting upper right ending lower right. Primary dentition use letters a-k
what is the succeduous dentition formula
I 2/2, C 1/1, PM 2/2, M 3/3
what does succeduous mean?
something that replaces somthing
are adult molars succeduous?
no, they don’t replace anything.
What are the 4 functions of teeth?
mastication, esthetics, speech, protection of supporting tissues
which teeth are considered anterior/ posterior teeth?
anterior- incisors & canines
posterior- premolars & molars
describe convexity or height of contour
this is the interaction of the gum with the tooth
which contour is on all teeth?
facial surface- on the cervical 3rd
where is the contour on lingual surface of incisors and canines
cervical 3rd of crown
where is the contour on lingual side of posterior teeth?
middle 3rd of crown
why is the countour higher up on the posterior teeth
it allows the tongue to sit on it
what does under contour result in?
reseeding gingiva do to lack of stimulation
what does over contour do?
causes irritation and swelling
where do you find proximal height of contour?
this is between adjacent teeth and prevents food compaction
why are lingual embrasures larger than facial?
the tongue can move food onto the occlusal surface.
Describe interdental papillae
gingiva that fills the gingival embrasure. ( anterior-triangle shape , posterior= mtn. range/col)
describe maximum intercuspal contact
best possible contact points for them ( fit like 2 hands clasped together)
what are groves for on cusps
to allow food to escape
what is the cervical margin junction
between crown and root
what is the anatomical crown
incisal edge to CMJ ( cervical marginal junction)
process of making enamel is called and is made by ?
amelogenesis, ameloblasts, these originate from ectoderm
what happens to ameloblasts when tooth erupts
they become desensitiezed
what 2 properties make enamel special
complex organization of matrix makes it hard, the mineralization makes it so it can withstand acids.
how is enamel organized
rods & interrods ( sometimes rod sheaths)
thickness of enamel
incisal ridges- 2mm, cusps of PM- 2.3-2.5, cusps of molars 2.5-3mm
T/F, each cusp comes from one single ossification center?
F, they have their own
describe what an enamel rod looks like
a tennis racket
what does a rod sheath do?
cements inter-rod
enamel anatomy
enamel rod, head, & tail
describe enamel lamella, stria of retzius, enamel tufts, and DEJ
describe them
what is gnarled enamel
group of enamel rods intertwined with adjacent rods. This adds strength. ( think knots in tree stump)
what are hunter schreger bands
optical appearances in enamel
what are enamel tufts
start in dentin and end in enamel, may play a role in spreading of caries
whats the purpose of enamel lamellae?
weak area predisposing a tooth to bacteria and caries
striae of retzius
growth rings of enamel, usually stain red
imbrication line of pickerill & perikymata
perikymata- elevated grooves
pickerill- valley of gooves ( these are kind of wavy)
prismless enamel and where its found.
outer layer of enamel found mostly towards cervical area. Its ~30micrometers thick.
what is cool about dentin
takes force away from enamel and distributes the forces out. ( granite pillow ex)
function of dentin-pulp complex
formative/ developmental, nutritive, sensory, defensive/ repariative
formation of dentin is____ and is by ____
dentinogenesis, odontoblasts
what are tomes fibers
long cytoplasmic cell processes of odontoblasts
is dentin dead or alive?
alive, it responds to stimuli
what is dentin derived from
odontoblasts which differentiate from ectomesenchymal cells. These are neural crest origin
mesenchymal cells can differentiate into what
lymphatic, circulatory and connective tissues
name 3 phases of tooth development
initiation, morphogenesis, histogenesis ( these are hard to distinguish because they all overlap
what is meckels cartilage
thickening bands around 37 days of dev. that form jaw bone
which laminae forms first dental or vestibular
vestibular then dental
what is a placode?
embryonic structures that give rise to structures like hair and teeth
what is an enamel spindle?
when an odontoblast becomes trapped in early enamel. They are by the DEJ
where is the predentin found
right next to the cell bodies of odontoblasts
Dentin forming the initial shape of tooth is called?
Primary dentin, usually complete after 3 years after eruption
describe the dentin tubule and tomes fiber relationship
tubules are the canal that tomes fibers occupy. They extend from DEJ to pulp
Dentin tubule size and location on the tooth
superficial tubules are smaller and less numerous. Deep tubules are larger and more numerous
tubules in the root compared to coronal
root are less numerous than coronal
starting most superficial name the types of dentin
mantle, primary, secondodary, predentin tertiary( spots by root)
primary dentin
“circumpulpal dentin”, mantle dentin is actually part of primary dentin and is mineralized differently.
secondary dentin
thin layer between primary and predentin. Secondary dentin formation is much slower than primary
what is pulp recession
deposition of secondary dentin around the pulp is asymmetrical
whats the purpose of the sclerose of secondary dentin
reduces the overall permeability of the dentin protecting the pulp
tertiary dentin
“reactive dentin”, is produced in reaction to various stimuli ( attrition, caries, or dental procedures)
what are the 2 classifications of tertiary dentin?
reactionary, reparative.
root dentin formation is by
requires proliferation of hertwigs epithelial root sheath
where do hertwigs cells come from?
cervical loop of the enamel organ. These cells differentiate into odontoblasts
what happens first tooth eruption or root formation?
when the tooth erupts the root formation is 2/3 done
epithelial rests of malassez cells
from fragmented rooth sheath. May participate in maintenance and regeneration of periodontal tissues
cementum
hard tissue that covers the anatomic roots, formed by cementoblasts, develop from mesenchymal cells in dental follicle
cementum %’s
45-55 hydroxyapatite, 50-55 % organic water and water
what are sharpeys fibers?
little extentions of PDL that anchor in the cementum and alveolar bone
T/F, Cementum is vascular
false
Name the 2 types of cementum
acellular, cellular
acellular cementum
** cementum is living**, acellular is mostly on coronal half of root
cellular cementum
mostly on oapical half of root.
Active eruption
normal movement the body does to position tooth in oral cavity
passive eruption
lengthening of crown do to loss of attachment or recession of gingiva
functions of incisors
cut food, enable articulate speech, help support lip and maintain esthetic appearance, guide mandible posteriorly when closing mouth
name the 5 sides of a tooth
mesial, distal, facial, lingual, incisal/occlusal
developmental lobes
tooth crowns develop from lobes or primary growth centers
name the facial lobes of an incisor
mesial, middle, distal,
name the lingual surfaces of an incisor
cingulum
width of incisal roots
wider faciolingually than mediodistally( exception is maxillary central incisor
