Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Ortho > 3rd year lectures key points > Flashcards

3rd year lectures key points Flashcards

1
Q

AP class 1

A

mandibular base 2-3mm behind maxillary base

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

AP class 2

A

maxilla more than 3mm in front of mandible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

AP class 3

A

maxilla less than 2-3mm in front of mandible (mandible may be in front)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

tx for skeletal discrepancies

A

growing pts - growth mod

completed growth - orthognathic surgery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

aims of tx

A

stable
fct
aesthetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

risks

A

decalcification
relapse
root resorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

benefits

A 
fct
aesthetics
dental health
reduce risk of trauma
facilitate other dental tx
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

why ortho assess?

A

determine if any malocclusion present
identify any underlying causes
decide if tx indicated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

when assess?

A

brief at 9yrs - interceptive ortho
comprehensive 11-12yrs - when 3s and 4s erupt
when older pts first present
if a malocclusion develops later in life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

ideal occlusion - Andrews 6 keys

A 
molar relationship
crown angulation
crown inclination
no rotations
no spaces
flat occlusal plane (no curve of Spee)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

normal occlusion

A

more common than ideal

minor deviations that do not contribute an aesthetic or fct problem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

malocclusions

A

more significant deviations from the ideal that may be considered unsatisfactory (aesthetically or fct)
may require tx but pt factors may influence decision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

PMH

A

allergy - Ni or latex
epilepsy - if not well-controlled avoid URA
drugs - some induce e.g. gingival overgrowth
imaging - delay tx until had scans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

PDH

A

freq attendance
prev tx
cooperation
trauma - RR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

dentoskeletal relationships

A

teeth on individual skeletal bases which are attached to the cranial base

  • maxilla - maxillary teeth and alveolus
  • mandible - mandibular teeth and alveolus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

ideal FMPA

A

meet at occipuit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

lateral skeletal assessment ref line

A

mid sagittal plane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

assessing skeletal pattern

A

visual

palpate skeletal bases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

effect of lip trap

A

may procline U incisors

may lead to relapse of OJ if persists at end of tx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

effect of hyperactive L lip

A

may retrocline L incisors

indicates likely instability at end of tx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

lips

A

competent/incompetent
trap
lower lip activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

which type of tongue thrust may cause a relapse of AOB?

A

endogenous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

tongue thrust associated with

A

AOB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

angulation of U incisors to Frankfort plane

A

110 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

angulation of L incisors to mandibular plane

A

90 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

types of tooth movement

A 
physiological
 - tooth eruption
 - mesial drift - U better
orthodontic
 - from externally generated forces
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

tooth eruption stages

A 
pre-eruptive tooth movement
intra-osseous eruption
mucosal penetration 
pre-occlusal eruption
post-occlusal eruption
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

pre-eruptive tooth movement

A

small random movement

rocks in crypt

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

intra-osseous eruption

A

when roots begin to form
slow
1mm/3m to 1mm/3yrs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

mucosal penetration

A

fast

1-2mm per month

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

pre-occlusal eruption

A

slow

stops when tooth hits something hard - when PDL begins to form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

post-occlusal eruption

A

v slow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

tooth eruption theories

A 
root elongation
alveolar bone remodel
PDL formation 
apical blood flow important
PTH receptor gene
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

interceptive tx

A

utilise tooth eruption to minimise impact of a developing malocclusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

interceptive tx - ectopic U C

A

remove c - 10-13yrs

permanent teeth can be encouraged ti erupt if extract primary tooth at correct stage - 1/2 to 2/3 root development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

prevalence of ectopic U3

A

1-2%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

when should you palpate for U3?

A

9-10yrs

buccal sulcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

things to assess when looking at ectopic U3

A

height
closeness to midline
- doesn’t overlap adjacent incisor by >1/2
- angle between vertical and canine ideally <30 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

physiological basis of tooth movement ortho

A

if external force applied to tooth - will move as bone around it remodels
bony remodelling mediated by PDL
- if ankylosed/no PDL will not move (will cause movement of other healthy teeth)
cementum much more resistant to resorption than bone
- but some RR after ortho expected
OBs and OCs
- appliances transmit force to PDL and bone
- phagocytosed by macrophages when stop functioning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

theories for ortho tooth movement

A

differential pressure theory
Piezoelectric pressure theory
mechano-chemical pressure theory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

differential pressure theory

A

force =
tension areas - deposition
compression areas - resorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Piezoelectric pressure theory

A

Piezoelectric currents generated when crystalline structures such as bone are deformed
compression side more +, tension side more -
- OB and OC get preferentially recruited to certain sides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

mechano-chemical pressure theory

A

mechanical stress
release of neuropeptides from nerve endings
stimulate FBs, endothelial cells and alv bone
FBs also comm with OBs and OCs
alv bone and PDL remodelling = tooth movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

force for tooth movement - tipping

A

35-60g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

force for tooth movement - bodily movement

A

150-200g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

force for tooth movement - intrusion

A

10-20g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

force for tooth movement - extrusion

A

35-60g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

force for tooth movement - rotation

A

35-60g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

force for tooth movement - torque

A

50-100g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

what movement do fixed appliances produce?

A

bodily movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

intrusion

A

pressure on supporting structures

resorption of bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

extrusion

A

tension in supporting structures

bone deposition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

functional appliances mechanism by which they work

A

skeletal changes 30%
- growth of mandible, restraint of maxilla
dentoalveolar changes 70%
- facial musculature stretched which generates forces transmitted to teeth and alveolus
- retroclination U teeth
- proclination L teeth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

light force

A 
hyperaemia within PDL
OB and OC appear
resorption of LD from pressure side
apposition of osteoid on tension side
remodelling of socket - frontal resorption
PD fibres reorganise
gingival fibres appear not to become reorganised but remain distorted
slow tooth movement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

mod force

A

occlusion of PDL vessels on pressure side
hyperaemia of PDL vessels on tension side
cell-free areas on pressure side (hyalinisation)
- no cells, not dead but nothing going on so can’t resorb
period of stasis
increased endosteal vascularity
undermining resorption
increased OC activity
= get OC coming in and nibble from below
sudden movement of tooth CLUNK
- tooth may become slightly loose
healing of PDL - reorganisation and remodelling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

rotation

A

need a force couple - 2 forces in opp directions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

excessive force

A 
necrosis
undermining resorption
resorption of root surfaces
pain
permanent change
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

factors affecting response to ortho force

A

magnitude
duration
age
anatomy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

deleterious effects of ortho forces

A 
pain and mobility
pulpal changes
RR
loss of alveolar bone support
relapse
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

rotational relapse

A

tend to rotate again due to supercrestal fibres

fibres will gradually move the tooth back after the appliance is removed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

aetiology of skeletal variation

A

genetic

env - MM, mouth breathing, head posture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

class 1 ceph

A

SNA 81 +/- 3
SNB 78 +/- 3
ANB 3 +/- 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

class 2 ceph

A

SNA usually average but may be increased if maxilla prognathic
SNB usually decreased
ANB >5 degrees

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

class 3 ceph

A

expect SNA decreased if maxilla deficient
SNB often average but may be increased if mandible prognathic
ANB <1 degree or negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

dento-alveolar compensation

A

dento-alveolar structures may disguise underlying skeletal discrepancy
forces from STs - incline teeth towards a position of ST balance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Frankfort plane clinical

A

lower orbital rim to superior border of EAM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

where do FMPA normally meet clinically?

A

EOP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

vertical facial proportions clinical landmarks

A

glabella
subnasale
soft tissue menton

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

vertical facial clinical proportions

A

50%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Frankfort plane ceph

A

orbitale to porion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

mandibular plane ceph

A

menton to gonion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

FMPA degree

A

27 +/- 4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

vertical facial proportions ceph landmarks

A

nasion
ANS
menton

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

vertical facial ceph proportions

A

45, 55

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

vertical jaw relationship - long facial height

A 
LAFH >55%
FMPA >31 degrees
steeply inclined mandibular plane
backward mandibular growth rotation
AOB tendency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

vertical jaw relationship - short facial type

A 
LAFH <55%
FMPA <23 degrees
tendency to parallelism of jaws
forward mandibular growth rotation
deep overbite tendency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

mandibular displacement

A

inter-arch width discrepancy causes posterior teeth to meet cusp to cusp
mandible forced to deviate to one side to achieve position of inter-cuspation
- association with TMD - one reason why you would treat it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

transverse jaw discrepancies: arch width discrepancies

A

disproportion of M and M arches
maxillary arch too narrow is the most common
causes buccal CBs
often exaggerated by AP discrepancies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

transverse dento-alveolar compensation

A

small maxilla - upper molars tend to flare outwards due to forces of tongue
moulding to compensate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

facial asymmetry causes

A

dental cause

true mandibular asymmetry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

arch size discrepancies - DA disproportion

A

discrepancy between size of teeth and jaws
crowding
- small jaws, normal teeth (most common)
- macrodontia
spacing
- large jaws, normal teeth
- microdontia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

aetiology of malocclusion

A

skeletal
dental
STs
other e.g. habits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

local causes of malocclusion

A 
variation in tooth number
variation in tooth size/form
abnormalities of tooth position
ST abnormalities
local pathology
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

variation in tooth number

A 
supernumeraries
hypodontia
variation of timing
 - retained primary
 - early loss primary
 - unscheduled loss of permanents
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

supernumeraries

A

tooth/tooth-like entity which is additional to normal series

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

where are most supernumeraries located?

A

80% in anterior maxilla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

prevalence of supernumeraries

A

1% in primary

2% in permanent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

types of supernumerary

A

conical
tuberculate
supplemental
odontome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

conical supernumerary

A 
most common anterior maxilla
small, peg shaped
close to midline, mesiodens
may erupt (extract)
tend not to prevent eruption/cause impaction but may displace adjacent teeth
parallax
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

supplemental supernumeraries

A

normal morphology
at end of a tooth series
often extract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

tuberculate supernumeraries

A

tend not to erupt - often associated with a failure of eruption
cause impaction of teeth
paired
barrel-shaped
usually extracted
one of main causes of failure of eruption of permanent upper incisors

92
Q

odontome

A

mass of P, D, E
can prevent eruption of teeth
compound/complex

93
Q

hypodontia prevalence

A

4-6%

94
Q

retained primary tooth

A

difference >6m between shedding of contralateral teeth

radiograph

95
Q

why are primary teeth retained?

A 
absent successor
ectopic successor/dilacerated
infra-occluded primary molars
 - trauma/idiopathic
dentally delayed
 - may be medical causes
pathology/supernumerary
96
Q

retained primary tooth - absent successor

A

maintain primary tooth for as long as possible (if good prognosis)
or extract early - encourage spontaneous space closure

97
Q

infra-occluded primary molar

A 
tooth fails to achieve/maintain its occlusal relationship with adjacent teeth
 - MRs not same height
often corrects
temp ankylosis
percussion sound
98
Q

infra-occluded primary molar - prevalence

A

common 1-9%

99
Q

slight infra-occluded primary molar

A

between occlusal surface and IP contact, <2mm

100
Q

mod infra-occluded primary molar

A

within occluso-gingival margins of IP contact

101
Q

severe infra-occluded primary molar

A

below IP contact point - likely extract

102
Q

management of infra-occluded primary molar - successor present

A

usually self-correct so keep under review
consider extraction if
- contact points going subgingival
- root formation of successor near completion

103
Q

infra-occluded primary molar management - successor absent

A

depends on potential of crowding

  • retain if good condition (onlay)
  • or extract and plan space management
104
Q

early loss of primary teeth - localisation of crowding depends on:

A

which tooth extracted
when tooth extracted
pts inherent crowding

105
Q

balancing ext

A

ext from opp side of same arch

minimise midline shift

106
Q

compensating ext

A

extract from opposing arch of same side

maintain occ relationship

107
Q

early loss of primary canines

A

consider balancing ext

as can get midline shift

108
Q

when does the early loss of primary teeth have most effect?

A

when primary teeth extracted early - little effect if extracted late
more space loss in U>L
marked space loss in crowded pts
minimal/no space loss in spaced dentitions

109
Q

compensating extractions if early loss of FPMs

A

U6 extracted - don’t compensate

L6 extracted - may need to compensate - depends on occlusal stops

110
Q

when should the prognosis of FPMs be assessed if considered ext?

A

age 8-9yrs

111
Q

balancing extractions if early loss of FPMs

A

consider if premolar crowding

112
Q

factors influencing impact of loss of 6s

A 
age at loss
 - U less important
 - L bifurcation development in 7s
    - too late - poor space closure
    - too early - distal drift of 5s
crowding
 - U potentially rapid space loss
 - L best results if crowded. if spaced/aligned - spaces
malocclusion
113
Q

loss of permanent central incisor

A

maintain space
- centre lines
reimplant

114
Q

variation in tooth size/form

A 
macrodontia
microdontia
abnormal form
 - aesthetics
 - pulp chamber morphology
115
Q

abnormalities of tooth position

A

ectopic

transpositions

116
Q

ectopic first molars

A 
<5%
U arch more common
reversible <8yrs
manage
 - separator
 - attempt to distalise 6
 - extract E
117
Q

incidence of ectopic canines

A

1-3% pop

80% palatal

118
Q

what are ectopic canines associated with?

A

small/absent U laterals

119
Q

assessment of canines

A 
clinical
 - palpation
 - inclination of 2
 - mobility of c/2
 - colour of c/2
radiographic
 - 2 - parallax
120
Q

tx options for ectopic canines

A

extract c - interceptive
retain 3 and observe
surgical and ortho
(surgical) extraction

121
Q

reasons for ectopic upper centrals

A

dilacerated (trauma)

supernumerary

122
Q

local abnormalities of STs

A

digit sucking
frenum
tongue thrust

123
Q

transposition

A

interchange in position of 2 teeth

124
Q

true transposition

A

apices in wrong place

125
Q

pseudo transposition

A

only crowns crossed

126
Q

treatment of transposition

A

extract one then close space
accept
(correct) if pseudo

127
Q

labial frenum

A

may cause median diastema
tx
- ortho
- frenectomy

128
Q

why shouldn’t you start tx straight after someone stops a non-nutritive sucking habit

A

might get some spontaneous correction

129
Q

tongue thrust

A

may cause AOB
endogenous e.g. Down syndrome macroglossia
exogenous e.g. incompetent lips, struggle to get a seal to swallow

130
Q

local pathology

A

caries
cysts
tumours

131
Q

what does ectomesenchyme form?

A

P
D
C
PDL

132
Q

how do the flat bones of the skull form?

A

IM ossification

133
Q

how does the base of the skull form?

A

endochondral ossification

134
Q

IM bone formation

A

bone deposited directly into primitive mesenchymal tissues
needle like bone spicules progressively radiate from primary ossification centres to periphery

vault of skull
maxilla
most of mandible

135
Q

endochondral bone formation

A

hyaline cartilage precursor
centres of ossification
base of skull
get islands of cartilage remaining to allow growth

136
Q

vault of skull growth

A

IM ossification in 3rd month in several centres
fontanelles
- anterior closes 2 years
- posterior closes 1 year
growth occurs at fibrous sutures in response to ICP
growth continues until 7 but some of the sutures remain open until adulthood

137
Q

embryonic facial cartilages

A

M and M develop IM, but develop adjacent to pre-existing cartilaginous skeletons - nasal capsule and Meckels cartilage
6 weeks
associated but don’t form it

138
Q

when does ossification of face and skull occur?

A

about 7-8 weeks

139
Q

mandibular processes

A

condylar unit
angular unit - in response to MP and masseter
coronoid unit - in response to temporalis
alveolar unit - only forms if teeth are developing
body - forms in response to IAN

140
Q

3 main sites of secondary cartilage formation in the mandible

A

condylar - disappears long before birth
coronoid - growth continues here until about 20yrs
symphyseal end of each half of bony mandible - disappears just after birth
appear 12-14 weeks IUL

141
Q

development of M and M

A

both IM but are preceded by a cartilaginous facial skeleton

142
Q

what precedes the mandible?

A

meckels cartilage

143
Q

what precedes the primary skeleton of the upper face?

A

nasal capsule

144
Q

primary abnormality

A

defect in structure/part of an organ that can be traced back to an anomaly in its development - spina bifida, cleft lip, CHD

145
Q

secondary abnormality

A

interruption of normal development of an organ that can be traced back to other influences

  • teratogenic agents: infection (rubella virus), chemical (thalidomide/lithium)
  • trauma, amniotic bands
146
Q

is a congenital abnormality always inherited?

A

no

147
Q

deformation

A

anomalies that occur due to outer mechanical effects on existing structures

148
Q

agenesia

A

absence of an organ due to failed development during embryonic period

149
Q

sequence

A

single factor results in numerous secondary effects

150
Q

syndrome

A

group of anomalies that can be traced back to a common origin

151
Q

facial syndromes arising from early problems with facial development (1-8 wks)

A 
env
 - foetal alcohol syndrome
genetic
multifactorial
 - hemifacial microsomia
 - Treacher collins syndrome (mandibulofacial dysostosis)
 - clefts
152
Q

FAS

A 
high maternal alcohol intake
day 17
microcephaly
short palpebral fissures
short nose
low nasal bridge
long and thin upper lip
deficient philtrum 
small midface
small mandible
mild mental retardation
153
Q

hemifacial microsomia

A 
3D progressive facial asymmetry
high arched palate
malformed pinna
ear tags
unilateral mandibular and zygomatic arch hypoplasia
normal intellect
clinical spectrum of severity
deafness, cardiac and renal problems
154
Q

TC - mandibulofacial dysostosis

A 
AD
deformity of first and second branchial arches
anti-mongoloid slant palpebral fissures
coloboma of lower lid
hypoplastic/missing zygomatic arches
hypoplastic mandible
deformed pinna, conductive deafness
155
Q

CLP aetiology

A 
genetic
env
 - smoking
 - alcohol
 - anti-epileptics
156
Q

dental features CLP

A 
cleft lip that crosses over alveolus causes dental anomalies
impacted teeth
crowding
hypodontia
supernumeraries
hypoplastic teeth
caries
157
Q

achondroplasia

A

problem with EC ossification
defects in long bones, short limbs = dwarfism
defects in base of skull, retrusive middle 1/3 of face, depressed nasal bridge

158
Q

crouzon’s (CF dysostosis)

A 
AD
premature closure of cranial sutures esp C and L
proptosis
mild hypertelorism
retrusion and vertical shortening of midface
prominent nose
class 3
distraction osteogenesis
159
Q

Apert’s (acrosyndactyly)

A 
AD
premature closure of almost all cranial sutures
maxillary hypoplasia
class 3, AOB
Parrot's beak nose
syndactyly of fingers and toes
CP association
conductive deafness
160
Q

differences between neonatal and adult skull

A

face small compared to cranium
eyes large
ears low set
forehead upright and bulbous
face appears broad
nasal region vertically shallow, nasal floor close to inferior orbital rim
- in adult mid face expands and nasal floor descends

161
Q

growth of the cranial vault

A

expands in response to growing brain until age 7
growth at sutures - deposition in response to raised ICP
shape modified by surface resorption/deposition
after neural growth ceases forehead continues to expand due to pneumatisation of air sinuses

162
Q

where does post-natal growth occur?

A

sutures
synchondroses - in cartilage
surface deposition

163
Q

post-natal growth - sutures

A

periosteal lined contact areas

flat bones grow laterally and bone deposited where sutures are

164
Q

post-natal growth - synchondroses

A

islands of cartilage remaining
between bones forming base of skull
in secondary cartilage of condyle and in cartilage of nasal septum
spheno-occipital synchondrosis
cartilage divides and areas pushed apart, turns to bone further away from the synchondroses

165
Q

post-natal growth - surface deposition

A

over surfaces of cranial and facial bones, beneath the covering periosteum

166
Q

growth of the cranial base

A

lateral growth completed by 3 years
sphenoethmoidal synchondrosis fuses at 6-7 yrs, after this the anterior CB is relatively stable and is used as baseline

growth ceases at SOS 12-15yrs and fusion by 20yrs

167
Q

post-natal growth of maxilla

A

downwards and forwards
growth at sutures, between maxilla and skull
surface deposition mainly posteriorly and resorption anteriorly and inferiorly

168
Q

post-natal growth of mandible

A

downwards and forwards
growth at condyle
surface resorption anteriorly and lingually with deposition posteriorly and laterally

169
Q

timing of stopping of facial growth - M and M

A

order M and M growth stops: width, length, height
width growth completed before pubertal growth spurt
length growth continues throughout puberty
- girls slows to adult rate 2-3yrs after 1st period
- boys around 18yrs
vertical height continues longest, declines to adult rate around 17-18 girls, early 20s boys

170
Q

sec difference in adolescent growth spurt

A

girls 1-2years earlier

for tx to coincide with growth spurt need to start earlier in girls

171
Q

growth rotations

A

forwards - short face
downwards and backwards - long face AOB
crowding of lower labial segment in late teens/early 20s - growth rotation

172
Q

adult facial growth

A

v variable
slowly throughout life
tendency to increased overall length and prominence of nose and chin and ears

173
Q

general direction of growth

A

downwards and forwards

but variations with growth rotations

174
Q

which skeletal problems can a lat ceph be used for?

A

AP and vertical

2D so can’t use for transverse problems

175
Q

analysis of lat ceph

A

relationship between jaws and cranial base
relationship between jaws
position of teeth relative to jaws
ST profile

176
Q

nasion

A

most anterior point of frontonasal suture

177
Q

gonion

A

most posterior inferior point on mandibular angle

178
Q

pogonion

A

most anterior point on mandibular symphysis

179
Q

menton

A

most inferior point on mandibular symphysis

180
Q

porion

A

upper midpoint on EAM

181
Q

orbitale

A

most anterior inferior point on IO rim

182
Q

ACB on lat ceph

A

sella-nasion

doesn’t change after age 7 so can use as ref point

183
Q

A and B

A

hard tissue - deepest concavity

184
Q

AP - class 1 ANB

A

2-4

185
Q

AP - ANB what can ortho be done on

A

8 to -3

186
Q

vertical MMPA angle

A

27

187
Q

vertical MMPA what can ortho be done on

A

17-37

188
Q

Ui/MxP

A

109 +/- 6

189
Q

Li/MnP

A

93 +/- 6

190
Q

Ui/Li

A

135 +/- 10

191
Q

rule of thumb for angles you can achieve with braces

A

U 120

L 80

192
Q

max movement with surgery

A

can only move M/M back/forward by 10mm

- if need >10mm do bimaxillary procedure

193
Q

interceptive ortho - diastema

A

wait until Cs erupt

<2.5mm should close

194
Q

ugly duckling stage

A

6 yrs 96% have diastema

canine crowns on distal of lateral roots

195
Q

causes of UE central incisors

A

supernumeraries
trauma/dilaceration
other pathology

v unusual to be congenitally missing

196
Q

UE central incisors due to supernumeraries management

A 
usually palatal
1 - remove deciduous and supernumeraries
2 - expose/bond
3 - create space
4 - monitor >1.5yrs
80% will erupt over 16m
197
Q

what does the effect of early loss of primary teeth depend on?

A

crowding
age
arch

anteriorly spacing so ok
posteriorly causes crowding as 6s come forward

198
Q

early loss of primary c’s

A

balance to prevent centre line shift

199
Q

tx of anterior CB

A 
tend to tx early (2s through)
z-spring
3 Adams clasps
 - need one at front
PBP so occlusion doesn't interfere
200
Q

extracting L FPM

A

need to compensate

don’t balance

201
Q

extracting U FPM

A

don’t compensate - don’t get over eruption in lower arch

202
Q

ideal time for ext of FPMs

A 
7s furcation forming - less likely to get severe mesial tipping
(8s present)
class 1
mod L crowding
mild/mod U crowding
U space closure much better
203
Q

when should you treat a posterior unilateral CB?

A

if displacement on closure

- distance between centre lines

204
Q

tx of a unilateral posterior CB

A

PBP - disocclude
6m would get correction
turn screw x2 per week
reciprocal anchorage

205
Q

when should habits be stopped by?

A

9yrs (within 3yrs of eruption)

206
Q

retained primary teeth

A

extract

207
Q

U canines development

A

palatal
migrate and lie labial and distal to root apex of U laterals
90% palpable by 11yrs
- if can’t then radiograph

208
Q

slightly enlarged canine roots

A

palatally placed

209
Q

diagnosis of infra-occluded primary teeth

A

percussion (hollow)
visually
radiograph (best)

210
Q

tx of infra-occluded primary teeth

A

successor present and mild (2mm or less) - observe 1yr

no successor - extract as likely to get worse

211
Q

consequences of leaving infra-occluded primary tooth

A

hard to keep clean

further submerged = harder to extract

212
Q

management of ectopic U C’s

A

extract c’s 11-12yrs
- if 3 not past midline of 2 - 90% success
- if 3 encroaching on 1 (significantly past 2) - 60% success
ensure enough space

213
Q

causes of a reverse OJ

A

dental e.g. retroclined uppers
skeletal e.g. class 3
both

214
Q

comprehensive tx

A

full correction of malocclusion
Andrew’s 6 keys
class 1 canines, incisors, molars

215
Q

compromise tx

A

correct certain aspects accepting others

e.g. accept buccal CB with no displacement - no fct problem

216
Q

stages of tx planning

A 
plan around L arch (LLS stable - just incisors)
 - plan everything around lower incisors
tx in lower
build U arch around L
 - canines must be class 1
molar relationship
 - class 1 or full unit class 2
217
Q

crowding assessment

A

measure space available and space required

overlap technique

218
Q

space required in L arch - mild

A

0-4mm
NE - stripping
E5s

219
Q

space required in L arch - mod

A

5-8mm
E5s (5mm)
E4s (6,7,8mm)

220
Q

space required in L arch - severe

A

8+ mm

E4s

221
Q

stripping

A 
metal sandpaper IP
enamel reduction
can get up to 3mm
 - 12 surfaces c to c
 - take off 0.5mm
222
Q

extracting L4 or L5

A

extract L4 - less mesial drift
only take out 5s if at mild end of crowding - won’t get enough space if severe
L4 is 7mm wide so get 14mm space if ext both
- if all the space needed need to reinforce anchorage (HG) - usually front teeth come back 50% and back teeth forward 50%

223
Q

if you ext in L arch what should you do in U?

A

E in U arch t get a MR class 1 (avoid class 3)

224
Q

if you don’t ext in L arch what should you do in U?

A 
1 - ext U arch - MR class 2
2 - distalise UBS with headgear (MR class 1)
225
Q

tx options

A 
accept malocclusions
E only
URA
functionals +/- ext
fixed +/- ext
complex tx
 - ortho and restorative
 - ortho and orthognathic surgery
226
Q

limitations

A

effects almost purely dentoalveolar and tooth movement

only remain stable where forces in equilibrium

Ortho (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions