Orthodontic Diagnosis

Question 1

what is the GDC definition of Orthodontics

Answer 1

development, prevention and correction of irregularities of the teeth, bite and jaws

Question 2

what are the aims of orthodontics

Answer 2

improve performance of the dentition

aim to provide long lasting adult dentition

Question 3

list 4 reasons why orthodontics is carried out

Answer 3

dental health
aesthetics
psychological well being
specific issues i.e not aligned, supernumerary etc

Question 4

define hypodontia

Answer 4

missing teeth

Question 5

define supernumerary teeth

Answer 5

extra teeth

Question 6

define overjet

Answer 6

horizontal distance between incisal edges of upper and lower incisors
AKA protrusion
increased in Class II div I

Question 7

define reverse overjet

Answer 7

class III
lower teeth further forward

Question 8

define overbite

Answer 8

vertical overlap of upper anterior teeth over lower anterior teeth

Question 9

define anterior open bite

Answer 9

anterior teeth don’t meet in occlusion

no overlap between upper and lower anterior

Question 10

define submerged teeth

Answer 10

deciduous
depressed below the occlusal plane
ankylosed to bone
mainly primary molars

Question 11

define crossbite

Answer 11

tooth is more buccal/lingual in comparison to other teeth in the arch

Question 12

define posterior cross bite

Answer 12

top posterior teeth bite down inside the lower posterior teeth rather than maxilla
due to narrow maxilla and upper dental arch

Question 13

define anterior crossbite

Answer 13

upper teeth sitting behind lower teeth

aka underbite or reverse overjet

Question 14

When does the mandible start to develop?

Answer 14

6th week inter-uterine life

Question 15

where are the maxilla and mandible derived from?

Answer 15

1st pharyngeal arch

Question 16

what is one of the earliest bones to develop in the head?

Answer 16

mandible- 6th week iu

Question 17

how is maxilla formed

Answer 17

intramemembranous ossification - 6th week iu

Question 18

define intramembranous ossification

Answer 18

direct laying down of bone into the connective tissue (mesenchyme)
dirrect differentiation of mesenchymal cells to osteoblasts
no cartilage is involved

Question 19

how does the maxilla grow

Answer 19

downs and forwards due to extensive remodeling and bony deposition at sutures within the naso-maxillary complex

Question 20

define displacement

Answer 20

growth which causes the mass of a bone to be moved in relation to other bones

Question 21

define drift

Answer 21

change in position of a bony stricture to to remodeling of that stricture

Question 22

how is the mandible formed

Answer 22

intramembranous ossification- 6th week iu

Question 23

at what age do teeth start to erupt

Answer 23

6 months

Question 24

when is primary dentition complete

Answer 24

3 years

Question 25

when does the permanent dentition start to form

Answer 25

6 years - 6s

Question 26

who can be given antibiotic prophylaxis for infective endocarditits

Answer 26

those consider in a special consideration group- SDCEP so need non-routine management

Question 27

what is phenytoin and what can it cause

Answer 27

anti-epileptic | gingival overgrowth/hyperplasia

Question 28

what is rheumatic fever and how is it linked to dentistry

Answer 28

an inflammatory disease which affects heart, joints, skin etc tends to occur after Group A streptococcal infection (strep throat or scarlet fever)

Question 29

what are side effects of bisphosphonates

Answer 29

delayed tooth eruption impaired bone healing osteoradionecrosis of the jaw

Question 30

what to do if someone has a severe bleeding disorder

Answer 30

avoid extractions if possible

Question 31

why should a diabetic patient have good OH

Answer 31

as risk of periodontal breakdown

Question 32

what advice should be given to a patient that uses an inhaler

Answer 32

rinse mouth and appliance after using inhaler

Question 33

what is recurrent apthous ulcerations

Answer 33

painful ulcers in oral mucosa | can be exacerbated by trauma from appliances

Question 34

give examples of habits that can cause problems

Answer 34

thumb sucking nail biting pen chewing musical instruments

Question 35

how should the patient be positioned when measuring the skeletal pattern

Answer 35

natural head position | teeth in maximum interdigitation

Question 36

in which 3 planes is a skeletal pattern assessed

Answer 36

anteroposterior- view from side vertical- viwe from side transverse- view from front and above

Question 37

what are the classifications of a skeletal pattern

Answer 37

Class I- mandible 2-3 mm posterior to maxilla Class II - mandible retruded relative to maxilla Class III- mandible protruded relative to maxilla

Question 38

what type of radiograph can be taken when assessing anteroposterior skeletal pattern

Answer 38

lateral cephalogram

Question 39

in which 2 ways can the vertical skeletal pattern be masuered

Answer 39

Lower facial height | FMPA- Frankfort mandibular plane angle

Question 40

Describe lower facial height

Answer 40

the distance from the eyebrow to the base of the nose should equal the distance from the base of the nose to the lowest point of the chin if the nose-chin distance is greater then the lower facial height is increased and if less than the eyebrow-nose then the lower facial height reduced

Question 41

describe FMPA

Answer 41

Frankfort Mandibular Plane Angle if the two meet at the back of the head, angle is normal if they meet beyond the back of the head, the angle will be reduced if they meet before the back of the head, angle is increased

Question 42

what can be measured to test the transverse skeletal pattern

Answer 42

occlusal plane symmetry- pt bites on to tongue spatula

Question 43

what can a tongue thrust cause

Answer 43

anterior open bite

Question 44

what are problems thumb sucking can cause

Answer 44

increased overjet open bite posterior crossbite narrow upper arch

Question 45

What should be observed with the labial segment

Answer 45

aligned, crowding, spaced | if any rotations or displacements

Question 46

how is crowding measured

Answer 46

mild- 4mm or less moderate- 5-8mm severe- >9mm

Question 47

what can be measured within the labial segment

Answer 47

overjet overbite centrelines anterior cross bite

Question 48

what should be observed within the buccal segment

Answer 48

crowding, rotations, displaced teeth | crossbites- unilateral/bilateral

Question 49

which radiograph would you take to observe overall dental assessment

Answer 49

DPT

Question 50

which radiograph would you take to check for skeletal discrepancies

Answer 50

lateral cephalogram

Question 51

which radiograph would you take to check for root resorption or check position on unerupted canine

Answer 51

upper anterior occlusal

Question 52

which radiograph would you take for assessment ofimpacted teeth or bone assessment of cleft lip and palate

Answer 52

CBCT

Question 53

what is IOTN and what are the 2 elements

Answer 53

index of orthodontic treatment need dental health component aesthetics component

Question 54

what is the dental health component

Answer 54

single worst feature is noted and categorised in one of the 5 grades

Question 55

what is 'mocdo'

Answer 55

``` to identify single worst feature for dental health component missing overjet crossbites displacement of contact points overbite ```

Question 56

what are the grades for the dental health component for IOTN

Answer 56

1- no treatment | 5- severe treatment need

Question 57

how is the aesthetics component measured

Answer 57

10 standard photographs | 1- most aesthetically pleasing

Question 58

what is the problem with the aesthetics component

Answer 58

``` can be subjective class III or anterior openbites not included in photos ```

Question 59

what equipment can be used to measure IOTN

Answer 59

IOTN ruler

Question 60

why are retention appliances important?

Answer 60

to prevent relapse