ALL ORTHO Qs Flashcards
(93 cards)
1
Q
aetiology of malocclusion (general)
A
skeletal - size/shape
muscle - form/function of muscles
dental - size of teeth in relation to jaw size
2
Q
AP jaw discrepancy -class 1 definition -class 1 features and ceph
A
maxilla 2-3mm in front of mandible
-ceph - SNA - 81+_3/SNB - 78+_3/ANB - 3+_2
3
Q
AP jaw discepancy - class 2 def -ceph features
A
-maxilla >2-3mm in front of mandible
ceph -SNA averege or increased/SNB - decreased
ANB>5mm
4
Q
what is the eastmen correction
A
For every >1 degree than average, subtract 0.5mm of ANB/vice versa
5
Q
AP jaw discrepancy - class 3 def -ceph features
A
mandible placed in front of maxilla
-SNA - decreased/SNB - average or increased/
ANB - <1 or negative
6
Q
what is dento-alv compensation
A
the inclination of the teeth that compensates for the underlying skeletal pattern
7
Q
how to determine AP jaw relationship
A
visual/palpate/ceph
8
Q
what are the measurement points of:
- frankfort plane
- mandibular plane
A
- frankfort - orbitale/porion
- mandibular - menton to gonion
9
Q
how to measure the vertical jaw relationship
A
FMPA - 27 degrees
LAFH - 50/50 clin 55% ceph
10
Q
what does a backward mandibular growth rotation produce, values:
- FMPA
- LAFH
A
steeply inclined mand plane, AOB tendency
- FMPA >31 degrees
- LAFH ->55%
11
Q
what does a forward mandibular growth rotation produce
- FMPA
- LAFH
A
Parallelism of jaws
deep OB
-FMPA - <23
-LAFH - <55%
12
Q
what are the two transverse discrepancies
A
arch width
mandibular displacement
13
Q
aetiology of malocclusion
A
skeletal dental ST BAD HABITS genetics and enviro
14
Q
local causes of malocclusion
variation in: (5)
A
variation in tooth number " in tooth size/form abnormality of tooth position local ST abnormality local pathology
15
Q
name 4 types of supernumerary and brief descriptions
A
- Conical - small peg shaped, mesiodens in midline
- Tuberculate - most likely cause of an unerupted central, paired/barrel shaped
- supplemental - extra teeth of normal morphology
- odontome - compound - many little teeth/complex - disorganised mass of dentine/pulp/enamel
16
Q
when should alarm bells be ringing in terms of delayed eruption.
-why would a tooth not erupt
A
6mth after contralateral tooth
-no perm successor/ankylosed/ectopic sucessor/pathology
17
Q
treatment for retained primary tooth if there is or is not a successor
A
if good prognosis, retain as long as poss, if no successor
If successor, ortho referral and consider XLA
Early ortho referral best
18
Q
management of an infra occluded primary molar
- perm succesor
- no perm successor
A
• Management:
– Permanent successor? Obs. 1 yr
– No successor? Extract, keep if good prog
19
Q
why would a tooth be lost early
- what is a balanced XLA
- what is a compensating XLA
A
trauma/caries/resorptio/early dental development
- balanced - tooth from opposite side of same arch
- compensating - tooth from opposing quadrant, minimise interference and maintain occ relationship
20
Q
what teeth should be balanced/compensated
A
A/B's - no comp/balance C's - balanced to prevent midline shift D’s – small CL. shift, balance under GA? • E’s – not to balance – major space loss – upper>lower
21
Q
when should children ideally be referred to an orthodontist
A
age 7-9yr
22
Q
what is the definition of interceptive ortho
A
‘Any procedure that will reduce or
eliminate the severity of a developing
malocclusion’
23
Q
Spacing percentages in primary dention that translate to crowding in perm dentition
-no spacing
-<3mm
-3-6mm
>6mm
A
- No spacing 66% crowding
- < 3mm 50% crowding
- 3-6mm 20% crowding
- > 6mm No crowding
24
Q
when should first perm molars be assessed, what should then happen
A
• Assessment 9 years
• Any doubts re long-term prognosis
refer for advice.
25
XLA rules of up/low 6's
If extracting lower XLA upper don't now necessarily extract upper!!
* Don’t balance with sound tooth.
26
what features display the best time to XLA 1st perm molars
```
Ideally:
* 7’s furcation forming
Mesioangulation of SPMs
* 8’s present
* Class 1 av/reduced OB
* Moderate lower crowding
* Mild/moderate upper crowding
```
27
on average, when are roots completed in a tooth
3yr post eruption
28
define leeway space and the measurements for max/mand
Leeway Space: difference between
e,d,c and 3,4,5.
– Mx 1.5mm
– Md 2.5mm
29
when should upper canines be assessed
```
10yrs
Assess position of upper canines from
10 years onwards
• Should palpate by 11 years
• Mobile C’s, symmetry
```
30
cause of deformity needing orthognathic surgery
family trait/race/congenital/deformity/trauma
31
Clinical exam prior to orthognathic surgery
E/O - AP relationship
front - vertical asymmetry/lip and nose morphology/horizontal asymmetry/ smile line
I/O - dental assessment/occlusal relationship/cetre lines/OJ/OB/incisor inclination/crowding/cleft
32
who's part of the multidisciplinary team of an orthognathic surgery team
psychologist/OMFS/restorative dentist/orthodontist/speech and language therapy/oral hygiene/technologist
33
How can combined ortho/surgical treament work
-tooth alignment/eliminate crowding/alteration or co-ordination of arches/correct incisor inclination/flatten occlusal plane/surgical fixation/post surgical ortho
34
diagnosis terms for:
maxilla
mand
chin
max - retrognathic/prognathic(anterognathic)/vertical excess/vertical deficiencey
mand-prognathic/retrognathic
chin - prognecia/retrognecia/vertical excess/vertical deficiency
35
name some surgical procedures in orthognathic surgery
max - le fort 1 osteotomy/anterior maxillary osteotomy
mand - andvancement (sagittal split osteotomy)/VSSO
chin - advancement, set back, rotation/augmentation/reduction
36
variation of tooth form
macrodontia
microdontia
abnormal
37
how many people are affected by ectopic canines (%)
1-2%
38
clinical assessment of ectopic canines
visualisation and palpation
colour /mobility of 2/c
inclination of 2
Rg - OPT and anterior occlusal for parallax
39
ectopic canine management
- leave and observe = prevention
- surgical exposure and ortho alignment
- XLA of c - encourage movement
- retain c and observe
- XLA
- Transplant
40
ectopic central incisor management
- surgical exposure
- XLA supernumerary
- bond gold chain
- ortho traction
- fixed appliance
- bonded retainer
41
class 2 div 1 definition
- what percetage of malocclusions
- main concerns
the lower incisor edges lie posterior to the cingulum plateau of the upper incisors. Incisors are often proclined/aaverage inclination and theres an increased OJ
- 15-20%
- aesthetics/trauma
42
```
class 2 div 1 features
-AP
-ST
Dental findings
-Habit
```
```
AP - class 1/2
ST - incompetent lips, try to achieve anterior oral seal
-through pushing lower lip up behind up incisors, use of circum-oral musculature, posture mandible forward
```
```
-dental features = >OJ, varied OB, good alignment and spacing, class 2 molar relationship
DRYING OF GINGIVAE - gingivitis risk
```
43
occlusal features of a sucking habit
proclined upper inc
retroclined low inc
narrow arch +_ unilateral post crossbite
AOB
44
management options of class 2 div 1
- accept
- growth mod - headgear/twinblock (functional app), 10yrs
- URA - robert's retractor
- fixed appliances
- Orthognathic surgery - pre and post ortho
45
mode of effet of functional appliance in class 2 div 1
DENTO-ALV CHANGE
distal movement of up dent/mesial movement of low dent/retroclination of up inc/proclination of lower inc
minor skeletal change
46
what features would encourage the use of a URA in class 2 div 1
favourable OB/mild class 1 or 2/OJ due to incisor proclination
47
```
class 2 div 2 definition
-% of all malocclusions
```
The lower incisor edges lie posterior to the cingulum plateau of the upper incisors. The upper incisors are often retroclined and there is a minimal OJ/slight increase
-10%
48
features of class 2 div 2
- AP
- Vertical
- ST
- Dental
AP-mild/mod skeletal class 2
Vertical - REDUCED FMPA, forward rotational mandible growth patttern
ST - high lip line/marked labiomental fold/high masseteric forces
-dental- retroclination of up incisors, reduced IIA/reduced OJ/2's crowded/mesio-labially rotated 2's
reduced arch length
>OB
49
treatment options for class 2 div 2
-accept and monitor
-Growth mod - mild/mod skel 2 = modified twin block
-Camouflage
Orthognathic surgery
50
what would occur during the camouflage stage of the treatment of a class 2 div 2
```
accept the underlying skel base and aim for class 1 incisor relationship = reduce OB
correct inter-incisal angle = palatal root torque - p incisors/procline lower incisors
```
51
```
class 3 definition
% of all malocclusion
```
the lower incisor edges lie anterior to the cingulum plateau of the upper incisors. There is a reversed or reduced OJ
-3-8%
52
features of class 3
- AP
- vertical
- transverse
- dental
-AP - class 3
-Vertical - May be associated with average, increased or
reduced vertical proportions
– Frankfort Mandibular Plane Angle
– Anterior Facial Height proportions
– Lateral cephalometry
• ↑FMPA and anterior open bite more complex
to treat
-Transverse- bilateral posterior crossbites
```
-Dental - Class III incisor relationship
• Class III molar relationship (not always)
• Tendency to reverse overjet
• Overbite will vary
• Crossbites
– Anterior and Posterior (buccal)
Alignment
– Maxilla often crowded
– Mandible often aligned or spaced
• Dentoalveolar compensation
– Proclined upper incisors
– Retroclined lower incisors
• Tendency for displacements on closing
```
53
treatment options for class 3
* Accept and Monitor
* Interceptive with URA - procline up inc over bite
* Growth Modification - reverse twin block/frankel III/chin cup/protraction heagear+RME
* Orthodontic Camouflage
* Orthognathic surgery
54
features of a frankel III appliance
```
Pellotes (Shields) labial
to upper incisors to
hold lip away
• Palatal arch to procline
the upper incisors
• Lower labial bow to
retrocline the lower
incisors
```
55
correct age and features for protraction headgear
```
Correct age (young age 9/10)
• Co-operative patient
• 14 hour/day protraction facemask wear
• 400g/side
• ± Rapid maxillary Expansion
```
56
favourable features for use of camouflage in class 3
Growth stopped
– Mild to moderate Class III Skeletal base ANB >0˚
– Average or increased overbite
– Able to reach edge to edge incisor relationship
– Little or no dento-alveolar compensation
57
order of ST exam
```
lip competent
lip trap
nasolabial angle
smile line
tongue
```
58
overview of intra-oral exam in patient assessment
- chart teeth
- poor prog
- OH
- tooth condition
- perio
- wear
59
Crowded measurements
| -methods of measuring crowding
```
<4mm - mild
4-8mm - mod
>8mm - severe
-space available/space required
-mixed dentition analysis
-overlap technique
```
60
Order of assessment IN OCCLUSION
- incisor class
- OJ
- OB
- centre lines
- molar relationship
- canine relationship
- crossbite
- mand displacement
61
definition of OJ
Horizontal distance between labial surface of tips of upper incisors and the surface of lower inc
62
definition of OB
vertical overlap of incisor teeth
63
special inv for ortho
Rg -OPT
study models
Planning models - Kesling (cut teeth off and move), Diagnostic - fixed pros
64
Problem list - MOCDOO meaning
```
Missing
OJ
Crossbite
Displacement of CP
OB
Other
```
65
CLP - how many
- % sporadic
- ratio of M:F
1:700 live births
70% sporadic
3M:1F
66
aetiology of CLP
genetic - fam H/syndrome/sex ratio/ethnic
| enviro - alcohol/drugs (antiep)/Low SES/smoking/multivitamins
67
CLP patient journey
3mth - lip closure
6-12mth - palate closure
8-10yr - alv bone graft
12-15yr - definitive ortho
18-20yr - orthognathic surgery
68
members of cleft care team
```
surgeon
cleft nurse
geneticist
ENT respiratory
psychologist
dental team
speech therapist
```
69
dental issues with CLP
```
hypodontia - missing teeth
caries
impacted teeth
crowding
growth
```
70
member of dental team for CLP
```
orthodontist
oral surgeon
paediatric dentist
restorative dentist
orthodontic therapist
dental therapist
```
71
basic order of orthopaedics
presurgical orthopaedics
expansion/bone graft
definitive ortho
orthognathic surgery
72
definitions:
- hypodontia
- anodontia
- severe hypodontia
```
Hypodontia
– Congenital absence of one or more teeth
• Anodontia
– Complete absence of teeth
• Severe hypodontia
– 6 or more congenitally absent teeth
```
73
prevalence of hypodontia, M:F
- most likely teeth
- prmary teeth occurence
Prevalence approx. 6% (excl. 8’s)
• 6.3% F, 4.6% M in European population
-lower 5's, upper 2's, up 5's
• 0.9% primary dentition
74
what are the clinical signs of hypodontia
```
Delayed or asymmetric
eruption
• Retained or infraoccluded deciduous
teeth
• Absent deciduous tooth
• Tooth form
```
75
what is the occurence % of missing laterals
1-2%
76
associated conditions and features of hypodontia
microdontia !!!!!!
cleft lip and/or palate
malformation of other teeth
short root anomaly
impaction
delayed formation and/or delayed eruption other teeth
crowding and/or malposition of other teeth
maxillary canine/first premolar transposition
taurodontism
enamel hypoplasia
altered craniofacial growth
77
name 2 conditions associated with hypodontia
ectodermal dysplasia
| down's syndrome
78
Hypodontia care pathway
GDP recognition
• Referral to Specialist Orthodontist
• If GDH&S: Initial assessment in Orthodontics
and allocate when appropriate to Hypodontia
clinic (Orthodontic & Restorative input)
79
assessment and planning components for hypodontia
```
History
• Extra-oral examination
• Intra-oral examination
– Orthodontic aspects
– Restorative aspects
• Investigations
• Problem list
• Definitive Plan
• Retention / maintenanc
```
80
special inv for hypodontia
```
Study Models
• Planning models
– Kesling, diagnostic
• Radiographs
• Photographs
• Conebeam CT
```
81
missing upper laterals - treatment options (general)
-detailed
```
Accept
• Restorative alone
• Orthodontics alone
• Combined orthodontic & restorative
treatment
```
```
-Open space / Close space
RBB
Implant
Autotransplantation
Conventional bridgework
Partial denture
```
CLOSE - Space closure plus
Simple
82
ADV and DIS of RRB
```
• Advantages
• Relatively simple
• Do when young
(complete treatment)
• Non-destructive
• Can look good
• Place on semipermanent basis
```
```
• Disadvantages
• Fail rate
• Appearance sometimes
not good, (try again,
new materials)
• Orthodontic retention
needs are high
```
83
fixed appliance ADV
| DIS
- move multiple teeth at once
- bodily movement
- no need for patient compliance
- control of root movement
- more complex tooth movement
dis
OH needs to be excellent
risk of iatrogenic damage
Poor intrinsic anchorage
84
components of a fixed appliance
```
brackets
modules
arch wire
band
anchorage components
force generating components
auxilliaries
```
85
what is torque
what is tip
bucco-lingual angulation of tooth
-determined by angle between bracket base and slot
tip - mesio-distal angulation of tooth
86
Properties of nickel titanium
shape memory
flexible
-light continuous force
>friction than SS
87
name 3 force generating components
elastic power chain/intraoral elastics/active ligatures
88
```
where do class 2 elastics fit onto
where do class 3 elastics fit onto
```
class II - low 6 to upper canine
class III - upper 6 to lower canine
89
name some forms of retention
- pressure formed retainer - cover all teeth, removable, easy to clear, can get lost/broken, easily replaced, can have prosthetic tooth for aesthetics
- hawley's retainer - labial bow
- resin bonded retainer - for rotation/diatema/space/ectopic canines
90
types of movement achieved using a quadhelix appliance
```
unilateral contraction
fan expansion
bilateral expansion of post teeth and canines
molar rotation
CLP expansion
asymmetrical expansion
```
91
what is the purpose of anance button and transpalatal arch
| -how much space between arch wire and GM
provide anchorage of molar teeth
| -4-6mm between arch wire and GM
92
risks of ortho treatment
```
relapse
gingival recession
decalcification
root resorption
loss of vitality
periodontal bone loss
failure of treatment
```
93
difference in adult treatment to children
| - issues
- lack of growth = growth mod not an option, OB treatment more difficult/can only expand max arch with surgery
- periodontal disease -
