OJ Reduction Flashcards
1
Q
Define Overjet
A
- Horizontal overlap of maxillary central incisors to Mandibular incisors
- Average 2-4mm
- IOTN a
2
Q
Risk of Trauma
A
- OJ more than 9mm = 2x trauma risk
3
Q
To Reduce increased OJ consider:
A
- Aetiology
- Growth
- Anchorage
4
Q
Aetiology of Increased OJ
A
- Skeletal- AP and vertical relationship
- Dental- ULS Proclined / LLS Retroclined / Both
- Habits- Digit / thumb sucking
- Soft tissues - lower Lip trap
5
Q
How growth aid reduction of OJ
A
- In most children AP- maxilla stop growth and Mandible grow which helps to reduce OJ
6
Q
Define Anchorage
A
- Resistance of unwanted tooth movement
7
Q
Reducing OJ by ?
A
- Retracting upper incisors
- Proclination of lower incisors
- Retrain maxilla growth
- enhance mandibular growth
8
Q
Headgear to reduce OJ
A
- Restrain maxillary growth
- Allow mandibular growth
9
Q
Inter maxillary elastics
A
- Retrouclination of ULS + Proclination LLS
10
Q
Extraction methods -upper extraction only
A
- Extraction of upper first premolars only
- Creating space anteriorly for OJ reduction
- Maintaining Increased posterior anchorage block
- What molar relationships ends?
11
Q
Extraction Choice Upper and lower extraction
A
- Upper first premolars and lower second premolars
- Creating space anteriorly for OJ reduction
- Forward movement of lower molars
- What would be molar relationship?
12
Q
In non growing patient
A
- Camouflage
- Orthognarhic depend on severity of SK Base
13
Q
OJ reduction - Working archwire
A
- Retract ULS or retract canine separately first
E.g closing loops
14
Q
Sliding mechanism
A
- Teeth are made to slide along the arch wire by energy stored in Elastic or wire coil spring
- Pre adjusted appliances facilitates sliding mechanism
15
Q
Sliding mechanism - Closing loops
Adv/ disadvantage
A
- Advantages :
- Minimal wire bending.
-Less time consuming - Easier to maintain arch form with closing loops
Disadvantages: - High friction with closing loop
-loss of anchorage - Can= uncontrolled tipping (if on light wire )
