Ortho midterm Flashcards
sibilant sounds
s and z
- problem= lisp
- anterior open bite and gap between incisors
labiodental fricatives
f and v
- problem= distortion
- skeletal class 3
lingudental fricatives
th, sh, and ch
- problem= distortion
- anterior open bite
angle classification
1= MB cusp of MX 1M in MB groove of MN 1M
2= MB cusp of MX 1M anterior to MB groove of MN 1M
div 1- incisors proclined
div 2- incisors retroclined
3= MB cusp is posterior
Lischer classification
what are the 3 normal ones?
axiversion=
toriservion=
transverse=
nuetrocclusion= normal class 1 position
distocclusion= MN teeth distal to normal (class 2)
mesiocclusion= MN teeth mesial to normal (class 3)
linguoversion and labio/buccoversion
infraversion and supraversion
axiversion= tipped along axis toriservion= twisted along axis transverse= incorrect position in arch
primary malocclusion dentition
- flush terminal plane=
- distal step=
- mesial step=
based on relationship of DISTAL surfaces of the 2nd molars
- flush terminal plane= distal surfaces same
- distal step= MN distal to MX (class 2)
- mesial step= MN distal surface is mesial to MX (class
What do they DEVELOPE into?
- flush terminal plane=
- distal step=
- mesial step=
- flush terminal plane= end to end or class 1
- distal step= class 2
- mesial step= class 3 or class 1
incidence vs prevalence
incidence= # of new cases prevalence= # over a period of time
facial types
- normalface = mesofacial
- long face= dolicho facial
- short face = brachyfacial
- mesognathic= striahgt jaws
- prognathic= MN protruded compared to MX (class 3)
- retronathic= MN retruded compared to MX (class 2)
profile types
- straight= glabella, subnasale and pogonion in line
- convex= Sn anterior to G and Pg
- cancave= Sn posterior to G and Pg
facial divergence
anterior= lower face slants anterior
posterior= lower face slants posterior
vertical proportions
* normalface = mesofacial
normal
* long face= dolicho facial
high MN, weak muscles, anterior bite
*short face = brachyfacial
low MN angle, strong musclesline of harmony
supraorbital ridge (glabella)
middle of ala of nose
chin (pg)
esthetic plane or E plane or ricketts plane
tip of nose
tip of chin
position of UL (4mm) and LL (2mm) from E plane
Ideal nasolabial angle?
men= 93-98
** increases with age
women= 95-100
cleidocranial dysplasia? genes?
Runx2 and Cbfa1
- no clavicle
- failure to shed baby teeth
- delayed eruption of perm teeth
- multiple supernumerary teeth
1) growth centers
2) growth sites
3) modeling
4) remodeling
1) location at which independent growth occurs (epiphyseal plates)
2) growth occurs (sutures)
3) bone size and shape can be changed
4) resorption by osteoclasts and apposition by osteoblasts
important hormones for bone remodeling?
OPG and RANKL
- both reliesed from stromal cell/osteoblast
- share the same receptor
- OPG stops reorption and RANKL causes it
compressive LOAD vs tensile strain
compressive load produces bone resorption (catabolic)
tensile strain leads to bone apposition (anabolic)
explain the 3 techniques to calculate crowding?
1) wire technique= bend wire and measure
2) segmental length= meaure 4 segments of arch
3) eyeball
measurements and what to do for no, mild, moderate and severe crowding
none- no txt
mild (1-3mm)- space maintainer, may need txt later
moderate (4-6mm)- space maintainer, refer
severe (7mm or more)- extractions
the size of ________ can predict the size of the unerupted permanent canines and PMs
permanent mandibular incisors
tanaka-johnson technique
sum of 4 perm MN incisors
* MN= sum/2 + 10.5
*MX= sum/2 + 11
THIS IS FOR 1 quadrant! need to double for arch!
moyer’s technique
sum of 4 perm MN incisors
*use table to predict space needed for both PMs and canine on each side
crowding is also known as?
tooth size - arch length discrepancy
true TSALD vs environmental? most common?
true= teeth to large
enviro= caries (most common)
trauma or malposition/eruption discrepancy
space maintainance for MX vs MN?
MX= band and loop and NANCE MN= band and loop and LOWER lingual holding arch
7 reasons mixed dentition should be txted?
1) functional habits
2) crossbites
3) psycho-social reasons
4) risk of trauma
5) habit reminder
6) ectopically erupting teeth
7) severe crowding needing series of extractions
why mixed dentition shouldn’t be treated?
class 3 skeletin cost/benefit cannot bevalidated
space availble vs space required
available= distal of first molar to distal of first molar
required= M-D width of teeth 6-6
bolten discrepnacy of ___ is not significant?
1.5mm or less
bolton overall analysis vs anterior analysis? RATIOS and what they MEAN!!!!
equation????
= (sum of MN/sum of MX)x100
overall= first molar to first molar
- <91.3 MN larger than MX
- > 91.3 MX is larger
anterior= canine to canine
- <77.2 MN teeth are larger
- > 77.2 MX larger
cranial base bones?
ethmoid
sphenoid
basioccipital
nasal capsule bones?
ethmoid
inferior concha
nasal septum
what happens in 4th month in-utero?
Ingrowth of vascular elements and appearance of centers of ossification
intra-membranous ossification and examples
secretion of bone matrix directly within mesenchymal condensation, without any intermediate formation of cartilage
** vault of skull, MN and MX
craniosynostosis
premature fusion of cranial sutures
craniometry vs anthropemetry
craniometry- precise measurement of dry skull
* cross sectional data
anthropometry- measurements of skeletal dimensions in living subjects with soft TISSUE
* longitudinal data aka FARKAS anthropometric studies
vital staining and examples
dyes that stain mineralizing tissue are injected into animal and later observed in bone/teeth once sacrificed
- tetracycline (yellow)
- calcein (green)
- alizarin red
- lead acetate
- xylenol (orange)
- demeclocline (gold)
gamma emitting isotope is used to detect areas of?
rapid bone growth
* useful in diagnosis of localized growth problems
autoradiography uses what in medium?
C-proline and H-thymidine
implant radiography
superimposing cephalometric radiographs on the implanted pins allows precise observation of BOTH 1) changes in the position of one bone relative to another and 2) changes in the external contours of individual bones
all tissue of face and neck originate from?
ectoderm (ectomesenchyme) that comes from nueral crest cells
what drugs can affect the formation and migration of nueral crest cells?
thalidomide and isotretinion
fate of meckel’s cartilage
malleus, incus
sphenomandibular ligament
anterior malleolar liagment
primary vs secondary jaw joint
primary
- meckel’s cartilage ends at malleus
- early jiont b/w malleus and incus
- exists for 4 months
secondary
- begins at 3 months
- two mesenchymal condensation:
1) temporal blastema appears first, ossifies first
2) condylar - which becomes cartilage
prenatal development of mandible
1) intramembranous ossification lateral to Meckel’s cartilage
2) center of ossification: appears at 6 weeks IU at bifurcation of inferior alveolar nerve
prenatal development of maxilla
1) intramem ossification (NO CARTILAGE)
2) 7 weeks IU
3) ossification center located at division nof superior dental nerve from inferior orbital nerve
malar cartilage is what and does what?
secondary cartilage that contributes to the development of maxialla
MX sinus begins forming when?
16 week in utero
3 branches of ortho
preventative
interceptive
corrective
potential undesirable effects of ortho?
1) compromised oral hygeine
* caries and soft tissue probs
2) decalcification
3) root resorption
