Orthodontics

Question 1

how do we assess symmetry?

Answer 1

line of fifths
birds eye view
worms eye view

Question 2

what are the landmarks for facial thirds to assess facial thirds?

Answer 2

glabella
subnasale
soft tissue chin

Question 3

what does it mean when FMPA meets behind occiput?

Answer 3

reduced FMPA

Question 4

what does it mean when FMPA meets ahead of occiput?

Answer 4

increased FMPA

Question 5

how are the maxilla and mandible positioned in class I skeletal pattern?

Answer 5

orthognathic

Question 6

how are the maxilla and mandible positioned in class II skeletal pattern?

Answer 6

maxilla forward
mandible back
combination of both

Question 7

how are the maxilla and mandible positioned in class III skeletal pattern?

Answer 7

maxilla back
mandible forward
combination of both

Question 8

what could increase the nasolabial angle?

Answer 8

proclined uppers
protruded maxilla

Question 9

what could decrease the nasolabial angle?

Answer 9

retruded maxilla
retroclined incisors

Question 10

what are the classifications for crowding?

Answer 10

mild - 0-4mm
moderate - 4-8mm
severe - >8mm

Question 11

what can cause a midline diastema?

Answer 11

frenal attachment
racial predilection
supernumerary - mesiodens
odontome, cysts
habits

Question 12

what are causes for generalised spacing?

Answer 12

missing teeth
microdontia
jaw size-tooth size discrepancy
perio problems
macroglossia

Question 13

describe class I incisor relationship

Answer 13

lower incisor edges occlude on or lie below the cingulum plateau of the upper incisors

Question 14

describe class II div 1 incisor relationship

Answer 14

lower incisor edge occludes behind the cingulum plateau of upper incisor
upper incisors normally inclined or proclined

Question 15

describe class II div 2 incisor relationship

Answer 15

lower incisor edges occlude behind the cingulum plateau of upper incisors
upper incisors retroclined

Question 16

describe class III incisor relationship

Answer 16

lower incisor edge occlude anterior to the cingulum plateau of upper incisors

Question 17

describe class I molar relationship

Answer 17

buccal groove of lower 6 occludes with MB cusp of upper 6

Question 18

describe class II molar relationship

Answer 18

buccal groove of lower 6 occludes posterior to MB cusp of upper 6

Question 19

describe class III molar relationship

Answer 19

buccal groove of lower 6 occludes anterior to MB cusp of upper 6

Question 20

describe the canine relationships

Answer 20

class 1 - upper distal to lower but touching
class 2 half unit- edge to edge
class 2 full unit - upper mesial to lower
class 3 - upper distal to lower not touching

Question 21

what age should you palpate for canines?

Answer 21

9-11

Question 22

what are the risk factors for impacted canines?

Answer 22

family history
females>males
class ii div 2
hypodontia/microdontia

Question 23

what % of impacted canines improve after XLA of C’s

Answer 23

78%

Question 24

when would you take xrays for ortho?

Answer 24

locate unerupted teeth
pathology
root morphology
assess skeletal pattern
monitor tx changes

Question 25

what is the nasion?

Answer 25

most anterior point of fronto nasal suture in median plane

Question 26

where is point A?

Answer 26

deepest midline concavity of anterior maxilla

Question 27

where is the PNS?

Answer 27

tip of posterior nasal spine

Question 28

where is point B?

Answer 28

the deepest concavity on the mandibular symphysis

Question 29

where is the pogonion?

Answer 29

most anterior point of mandibular symphysis

Question 30

where is the menton?

Answer 30

most inferior point on mandibular symphysis

Question 31

where is the gonion?

Answer 31

the constructed point of intersection of the tangents of the ramus plane and the mandibular plane

Question 32

what does an increased SNA angle indicate?

Answer 32

prognathic maxilla (>82 degrees)

Question 33

what does an decreased SNA angle indicate?

Answer 33

retrognathic maxilla (<82 degrees)

Question 34

what does an increased SNB angle indicate?

Answer 34

prognathic mandible (>80 degrees)

Question 35

what does a decreased SNB angle indicate?

Answer 35

retrognathic mandible (<80 degrees)

Question 36

what does an increased ANB angle indicate?

Answer 36

Class II skeletal pattern (> 4 degrees)

Question 37

what does a decreased or negative ANB angle?

Answer 37

class III skeletal pattern (<2 degrees)

Question 38

what are the risks of orthodontic tx?

Answer 38

demineralisation/caries relapse length of tx root resorption pain/discomfort appliances breaking failure to achieve desired outcome gingivitis ulceration

Question 39

what does IOTN stand for?

Answer 39

index of orthodontic treatment need

Question 40

what are the 2 components of the IOTN?

Answer 40

dental health aesthetic

Question 41

what does MOCDO stand for?

Answer 41

Missing Overjet Crossbite Displacement (of contact points) Overbite

Question 42

what DHC and AC scores would get priority tx?

Answer 42

DHC >4 AC >6