G and D final exam sg

first sign of tooth development

6-7 weeks in utero

deciduous teeth begin to calcify

13-20 weeks in utero

deciduous teeth erupt

6-30 montsh

what are the five stages of crown formation

1. initiation

2. bud stage

3. cap stage

4. bell stage

5. enamel and dentin formation

what are the three stages of tooth development

1. crown formation

2. root formation

3. supporting structures

incisors develop from the ________

medial nasal process

the primary epithelial band gives rise to the _______ and ________

dental lamina and vestibular lamina

presumtive incisor region

BMP4, islet 1

presumptive molar region

FGF8, FGF9

Shh, Lef-1, & Eda-Edar are involved in what?

placed formation

key signaling center consisting of non-dividing cells determines cusp formation

enamel knot

cells in the _________ synthesize glycosaminoglycans into the ECM

enamel organ

increase in _______ force the cells apart leading to formation of star shaped stellate reticulum cells

fluid volume

Spry KO leads to _______

additional tooth formation

stratum intermedium formation occurs during what stage

bell stage

at what stage does the crown attain full size and shape

bell stage

Osr 2 KO leads to....

incorrect orientation of tooth development

the junction of the IEE and OEE is called _______

cervical loop

the cervical loop is the future site of the ______

CEJ

in the late bell stage, under the influence of IEE, mesenchymal cells differentiate into _________

odontoblasts that makes dentin

once the mesenchymal cells differentiate into odontoblasts that makes dentin, IEE differentiate into ameloblasts and _______

make enamel

T/F

the initial secretory stage of ameloblasts has no Tome's process

true

T/F

the secretory stage if ameloblasts has no Tome's process

FALSE

secretory stage ameloblasts forms ________ and ______

enamel rod (R) and inter-rod (IR)

secretory stage ameloblasts secrete granules on the newly formed ______

mantle dentin

first layer of dentin formed by the newly differentiated odontoblasts, hypo mineralized, and only in the crown of the tooth (30-50 um thick)

mantle dentin

formed during tooth development (4 um/day)

primary dentin

dentin formed after tooth eruption (0.4 um/day)

secondary dentin

IEE and OEE from the cervical loop proliferate downward to form double layered structure called ____________, also the site of the CEJ

Hertiwig's epitelial root sheath

during ________ formation, fragmentation of HERS

cementum

understanding of the genes that are expressed or not and the level of expression, this can determine malocclusion

epigenetics

the equilibrium theory of proffitt says the _________ is more important than magnitude

duration of force

no growth centers in the craniofacial complex except the ________

cranial base

growth _______ are responsible for growth of long bones

growth centers

growth _________ are cells layered in a precise manner

centers

growth ________ - transplanted cell will continue to grow (due to tight genetic control)

centers

growth _________ = condyles, sutures, tuberosity

sites

growth _________ have immature fibrocartilaginous cells (not layered)

sites

T/F

growth sites stop functioning if transplanted

true

growth sites are sensitive to mechanical _________

stimulations

mandibular plane angle, y axis, and braciocephalic + normocephalic + dolychocephalic are the best _______

growth "predictors"

age of female growth spurt

10-12 years old

age of male growth spurt

12-14 years old (until 17)

stimulation of periosteal growth by altering the neuromuscular environment, this appliance will stimulate periostea pull and bone apposition

Frankl appliance

T/F

the Frankl appliance is not a tooth borne appliance

true

a maxillary expansion appliance can make the maxilla ________ wider

4-6 mm

wider than ______ will only make the teeth tilt

7

mid palatal suture doesn't calcify but it becomes set by the age of ______

12-14

sutures = growth _____ because it responds to mechanical stimulus like orthodontics

site

until the age of 7, maxillary growth is mainly ______ growth

sutural

once sutural growth is completed (~10 yrs old), antero-posterior growth is the result of growth in the ________

tuberosity region (growth site)

T/F

vertical growth is mostly likely epigenetic

true

resorption near molar, apposition on posterior portion

drift

displacement grows _______

anterior-inferior

Meckel's cartilage is made of _________ cartilage formed in the mandibular process of the _____ branchial arch of vertebrate embryos

hyaline ; 1st

Meckel's cartilage is located on the ________ aspect of mandible

posterior

mandibular alveolar process is tied to _________

dental eruption

Mandibular alveolar process vertical development

Significant vertical development

Where does mandibular alveolar process development take place?

Above the mandibular canal

What bone makes up most of the mandible?

Cortical bone

What bone makes up the area between teeth in the mandible?

Cancellous bone

meckel's cartilage growth (condyles) is ________ driven

genetically

alveolar vertical growth (dental eruption) stops when __________ is made

occlusion

it has been confirmed by the implant technique that growth in length of the mandible in man occurs essentially at the _______

condyles

the mandible "catches up" as it starts as ___________ at birth

retrognathic

_________ and ________ growth of the ramus occurs at the same time and must be timed with tooth eruption

vertical and transverse

condyles will grow in different directions in each person, what does this determine?

class 1-3

endochondral growth is present but only at the _________ of the condyle because of compressive load

articular surface

deciduous teeth

20 teeth

permanent dentition

32 teeth

larger spaces called "primate spaces" are found ________ to upper cuspids and ______ to lower cuspids

mesial ; distal

the upper incisors erupt to the _______ of primary teeth

labial

lower incisors tend to erupt to the _______

lingual

there is ________ in arch size during the eruption of the permanent incisors

no significant increase

T/F

some primary posterior teeth are larger than their successor

true

which primary teeth are larger than its successor

the primary maxillary and mandibular 2nd molars, which are both larger than their successors which are the permanent maxillary and mandible 2nd premolars

the __________ passes through the occlusal cusps of the posterior teeth and the incisor edges of the maxillary incisors

maxillary occlusal plane

the mandibular occlusal plane is ______ to the occlusal cusps of the posterior teeth and the incisal edges of the mandibular incisors

tangent

normal occlusal changes are due to ________, NOT from dental changes

skeletal growth

altering functional environment or neuromuscular pattern or introducing habits such as digit sucking can alter skeleton and occlusion resulting in

malocclusion

measured at the midline to a tangent touching the distal surfaces of the second primary molars

arch length

measured between the cusps of the canine tips in the transverse plane

arch width

difference between M/D crown widths of the primary canines + molars and the permanent canines + premolars

Lee Way Space

measured from the distal 2nd primary molar around the arch over the contact points and incise edges in a smoothed curve

arch perimeter

t/f

elongation of roots have nothing to do with tooth eruption

true

permanent 1st molars erupt to the distal of the __________

primary dentition

fusion of part of the root of a primary tooth to the underlying bone, which stops the tooth from eruptin

ankylosis

more than deciduous teeth, the sequence of permanent mention is ________

variable

T/F

girls are ahead of boys in calcification (except for 3rd molars) and in eruption

true

t/f

children who erupt any tooth early or late tend to acquire others early or late

true

different eruption sequences explain most_________

crowded teeth

Local influence that hastens permanent tooth eruption (pathosis)

Localized pathosis, such as periapical lesions of a primary molar.

Local influence that hastens permanent tooth eruption (extraction)

Primary tooth extraction during active eruption, with more than 2/3 of root formed.

Local influence that slows permanent tooth eruption

Primary tooth extraction before active eruption (before root formation starts).

t/f

arch width changes are small while arch length is a larger change

true

no significant increases in inter canine width occur in either the maxilla or mandible _________ the eruption of permanent canines

after

cause, set of causes, or manner of causation of a disease or condition

etiology

predisposing factors to malocclusion

- disturbances in embryological development

- heredity

- functional matrix

- traumas

what is the primary factor predisposing factor to malocclusion

heredity (genetics)

___________ is characterized by underdevelopment of the mid face and bulging eyes, along the wall of the orbit

Crouzon syndrome