BDS3 ortho assessment

Question 1

what is Ideal occlusion?

Answer 1

 Rare
 1. Molar relationship
* Distal surface of disto-buccal cusp of upper first molar occludes with mesial surface of mesio-buccal cups of lower 2nd molar
 2. Crown angulation
 3. Crown inclination
 4. No rotations
 5. No spaces
 6. Flat occlusal planes
(Andrews 6 keys)

Question 2

what is malocclusion?

Answer 2

 Are more sig deviations from the ideal that may be considered unsatisfactory (aesthetically or functionally)
 May require tx but pt factor may influence decision

Question 3

what must you ask about in relation to PDH for ortho exam?

Answer 3

 Ask about trauma to permanent dentition
* History of trauma
* Root resorption?
* RCT?

Question 4

what habits are important to know of when doing ortho exam?

Answer 4

• Thumb sucking
• Lower lip sucking
• Tongue thrust
• Chewing finger nails

Question 5

what are competent lips?

Answer 5

• Competent – lips meet at rest
  o Relaxed mentalis M

Question 6

what are incompetent lips?

Answer 6

o Lips that do not meet at rest
o Relaxed mentalis M

Question 7

what is a lip trap? and what could a relapse lead to?

Answer 7

• May procline upper incisors
• May lead to relapse of overjet if persists at end of tx

Question 8

what would hyper active lower lip do?

Answer 8

retrocline lower incisorS

Question 9

What should you know about tongue when doing ortho exam?

Answer 9

 Position
 Habitual
 Swallowing

Question 10

in terms of tongue position and swallowing pattern when doing ortho exam what should you know?

Answer 10

• Tongue position and swallowing pattern
  o Tongue thrust on swallowing can be associated with an anterior (AOB)
  o Can be either endogenous or adaptive tongue thrust (cause or effect?)
  o May cause relapse of AOB at end of tx if endogenous

Question 11

what are occlusal effects of a thumb habit?

Answer 11

o Proclination of upper anteriors
o Retroclination of lower anteriros
o Localise AOB or incomplete OB
o Narrow upper arch +/- unilateral posterior cross bite
o Remember that effects will be superimposed on existing skeletal pattern and incisor relationship

Question 12

what should you know about TMJ when doing ortho exam?

Answer 12

• Patho of closure
• Range of movement
• Pain, click from joint
• Deviation on opening
• Muscle tenderness
• Mandibular displacement
  o Discrepancy in retruded contact position and inter cuspal position
  o RCP does not equal ICP
  o Displacement of mandible up and to the right from RCP to ICP -note center line position

Question 13

what are the 3 planes facial skeleton is considered in?

Answer 13

• Antero-posterior
• Vertical
• Transverse

Question 14

what is a class I skeletal?

Answer 14

maxilla 2-3mm in front of mandible

Question 15

what is a class II skeletal?

Answer 15

maxilla more than 3mm in front

Question 16

what is a class III skeletal?

Answer 16

mandible in front of maxilla

Question 17

how do you check skeletal bases?

Answer 17

• Direct palpation of skeletal bases

Question 18

how is vertical skeletal assessment done?

Answer 18

Frankfort – mandibular planes angle (FMPA)

Question 19

how is lateral skeletal assessment done?

Answer 19

Mid sagittal ref line

Question 20

what must you assess during IO for ortho exam?

Answer 20

• Crowding
• Space
• Rotations
• Palpate for canines if not erupted
• Note teeth of abnormal shape/size e.g peg lateral
• Lower arch – angulation of incisors to mandibular plane – upright, proclined, retroclined
• Upper arch – angulation of incisors to Frankfort plane – upright, proclined, retroclined
• Teeth in occlusion

Question 21

what do you check when teeth in occlusion during ortho exam?

Answer 21

Max interdigitation or RCP

Question 22

what involves with checking max interdigitation or rcp?

Answer 22

 Incisor relationship
 Overjet
 Overbite/ open bite
 Molar relationship (angle’s classification)
 Canine relationship
 Cross bites
 Centre lines

Question 23

what is incisor relationship classes?

Answer 23

o Class I
 Lower incisor edges occlude with or lie immediately below cingulum plateau of upper central incisors
o Class II
 Lower incisor edges lie posterior to cingulum plateau of upper incsiors
 Division 1
- Upper incisors are proclined or of average inclination there is an increase in overjet
 Division 2
- Upper central incisors are retroclined. The overjet is usually minimal or may be increased
o Class II
 Lower incisor edges lie anterior to the cingulum plateau of the upper incisors. The overjet is reduced or reversed

Question 24

what does molar relationship (angle’s classification) also mean?

Answer 24

buccal segment relationship

Question 25

what is involved with buccal segment relationship?

Answer 25

• Angles classification
  o Class I
  o Class II
  o Class III
• Crossbites

Question 26

what do you compare patient to parent for?

Answer 26

 Malocclusion
* Especially class 3 malocclusions
 Growth potential

Question 27

what radiographs can you do for ortho exam?

Answer 27

 OPT
 Maxillary anterior occlusal
 Lateral cephalogram

Question 28

what is this and what are subtypes

Answer 28

Question 29

Answer 29

Question 30

Answer 30

Question 31

Answer 31

Question 32

what is this example of?

Answer 32

crossbites