Collecting The Data

Question 1

Orthodontic Diagnosis

Answer 1

Consists of 4 important separate stages

Collect the data –describe the malocclusion
Create a problem list
Decide the treatment aims
Decide the treatment means

Question 2

Aetiology of Malocclusion

Answer 2

Skeletal factors
Soft tissue factors
Dento-alveolar factors
Habits

Question 3

How can we measure Skeletal Pattern?

Answer 3

3 aspects
1- Antero-posterior (Skeletal Class)
Kettle’s method or Zero Meridian line

2-Vertical
Facial thirds or Frankfort-Mandibular Planes Angle (FMPA)

3-Transverse
Facial fifths / observation of significant asymmetry

Question 4

AP skeletal relationship –Skeletal Class 1 2 3

Answer 4

Class 1-The maxillary dental base lies2-3mm anterior to the mandibular dental base.

Class2- The maxillary dental base lies more than 2-3mm anterior to the mandibular dental base.
whentheteethareinocclusion.

Class3- The maxillary dental base lies less than 2-3mm anterior to the mandibular dental base.

Question 5

Kettle’s Method of Assessing Skeletal Class?

Answer 5

Class 1 - horizontal wrist position =
contact with A and B point simultaneously

Class2- wrist drops towards the floor -
contact with A point before B point

Class3- wrist moves upwards - contact
with B point before A point

Question 6

Why does Skeletal Class matter?

Answer 6

The bigger the skeletal discrepancy, the bigger the problem

The incisor relationship may not faithfully reflect the skeletal pattern because of:
Dento-alveolar compensation

Question 7

Definition of Dento-alveolar Compensation

Answer 7

When the A/P jaw relationship is skeletal class2 or 3 but SOFT TISSUES (lips, tongue, and cheeks) tend to guide the erupting teeth into better position than skeletal relationship would suggest.

So mild class 2 or 3 skeletal relationship the incisor classification may still be class 1

Question 8

Dento alveolar compensation in a patient with class 2 skeletal pattern.

Answer 8

Proclination of the lower incisors.

Question 9

Dento alveolar compensation in pt with class 3

Answer 9

Proclination of upper incisors
Retroclination of lower incisors

To acheive Incisal contact

Question 10

How do we diagnose vertical proportions?

Answer 10

• facial third / Average vertical facial proportion A=B or A slightly bigger
  -Mandibular plane and fronkfort plane (FMPA).
  Meet at occiput = average
  Meet before occiput= increased
  Don’t meet or after occiput = reduced

Question 11

Why does increased lower face height matter?

Answer 11

1- May cause reduced overbite or anterior open bite (which need jaw surgery to correct)
2- The patient may not like look of long face

Question 12

Why does reduced face height matter?

Answer 12

1- May cause deep overbite (hard to work to reduce)
2- Increased overbite traumatic bite.

Question 13

Facial Asymmetry associated with?

Answer 13

Intra oral feature :
- centre -line discrepancies
- posterior cross bites +/- mandibular displacements

Question 14

Define Mandibular displacement?

Answer 14

It’s the difference between the ICP and RCP, if it’s over 1mm.

Forward slide, could be right or left

Question 15

What’s influence of soft tissue?

Answer 15

Teeth come to lie within neutral zone( zone of force equilibrium)

Question 16

Why do lips matters in treatment?

Answer 16

• incompetent lip may result relapse of tx like corrected overjet increased
• same lower lip line- corrected overjet increased
• short upper lip -unattractive smile
• mouth breathing , cause gingivitis
• class 2. Div 1 , lip trap
  Class 2 div 2, lower lip retroclines upper centrals and lateral are short in height so less influence

Question 17

What tongue has effect on?

Answer 17

Habit- tongue thrust habit can cause anterior open bite AOB due to bimaxillary Proclination.

Question 18

Digit habit cause?

Answer 18

Asymmetric open bite

Question 19

Labial segment crowding from where?

Answer 19

Midpoint of canine forward.

Always start from front to back . And lower arch first

Question 20

Crowding classification

Answer 20

Mild- less than 4mm
Moderate - 4mm-8mm
Severe - more than 8mm

Question 21

Buccal segment crowding?

Answer 21

Midline of canine backwards

Question 22

Canine angulation

Answer 22

Mesial angulated canine- tip of crown towards mesial
Distally angulated canine. - tip of crown distally

Question 23

Incisor relationship

Answer 23

Class 1 - lower incisors occlude on cingulum plateau of the upper central incisor

CLASS 2- lower incisors occlude above cingulum plateau of the upper central incisors

Class 3- lower incisors occlude below cingulum plateau of the upper incisors

Question 24

Overjet

Answer 24

Horizontal overlap of the incisors measured 2-4 mm average

Question 25

Overbite

Answer 25

Vertical overlap of incisors measures 2-3mm or 1/3 coverage of lower incisors by upper.

It can be complete or incomplete

Question 26

Centre lines

Answer 26

Upper and lower centre line are recorded in relation to facial midline.
Upper- nose or philtrum
Lower- midpoint of chin

Non co incidence can be sk, dental, soft tissue. Play important role in tx planing mechanism

• Centreline off more than 4mm or more is discrepancy

Question 27

Buccal segment relationship

Answer 27

AP - molar relationship
Vertical - lateral open bite
Transverse - cross bite and scissor bite

Question 28

Molar relationship

Answer 28

Class 1- mesio buccal cusp of upper first molar occlude mesiobuccal groove of lower first molar.

Class 2- mesiobuccal buccal cusp upper of first molar rest between first mandibular molar and second premolar

Class3- mesiobuccal cusp of maxillary first permanent molar occlude distally to mesiobuccal groove of mandibular first molar.

Question 29

Intra oral data collection

Answer 29

• General dental health
• lower arch first
• front to back
• upper arch next
• occlusion

Question 30

Consent Level for photos

Answer 30

• Level 1 Pt record
• Level 2 Education
• level 3 - Practice advertising

Question 31

Photos should store till ?

Answer 31

• Till age of 25 for 11 years