functional appliances in ortho

Question 1

what do functional appliances

Answer 1

change the position of the mandible
stretches muscles of mastication
modify growth

Question 2

what do functional appliances do to md

Answer 2

open and forwards
bring consul out of the glenoid fossa

Forwards (i.e. protruding)
 Vertically (opening the bite)
 Stretches the muscles
 Transmits forces to the teeth (tooth movements)  May influence or take advantage of jaw growth

Question 3

who are functional appliances used on

Answer 3

its with class 2 div 1
class 2 molars
actively growing

 Well aligned arches
 Low FMP angle

Question 4

assessment of skeletal pattern

Answer 4

clinical

cephalometric

Question 5

what angle measures Md extrusion/class

Answer 5

ANB
anything greater than 4 degrees is a class 2

Question 6

when should you avoid functional appliances

Answer 6

non motivated patietns
class I molar relationship
high MMPA ie FMA (Md/mx planes angle)
those with increased lower face height - functional appliances can increase this angle

Question 7

when is the ideal time for functional appliance

Answer 7

late mixed/permanent dentition (usually want 1st permanent molar)
motivated
physically growing

Question 8

ways of measuring standing height

Answer 8

height curve

velocity curve

Question 9

height curve

Answer 9

cumulative

skeletal growth

Question 10

velosity curve

Answer 10

rate of growth per year

incremental growth

Question 11

types of functional appliances

Answer 11

twin block
activators
Frankel

Question 12

twin block

Answer 12

separate upper and lower applaince
midline screw in upper (expand arch)
prevents lower teeth going into cross bite
allows mx to reach a wider path of md compared to mx

Question 13

advantages of twin block appliance

Answer 13

1) aesthetic
2) patient can move the mandible
3) full time wear
4) robust
5) can expand upper arch/reactivate
6) integrate with fixed appliances

Question 14

medium opening activator

Answer 14

one block fitting over upper teeth
leaves a space between posterior to allow eription
helps correct deep overbite

Question 15

Frankel appliance

Answer 15

soft tissue borne
- shields alter the soft tissue balance
not clipped onto the teeth
bulky to wear

Question 16

dental effects of functional applianes

Answer 16

1) Upper labial segment retro clines
2) lower labial segment proclines
- helps correct class II incisor relationship
3) controlled eruption of lowers into class I
- molars and premolars will tend to erupt mesially and anteriorly, not just upwards

Question 17

skeletal effects of functional appliances

Answer 17

1) movement of md
- condyle growth
2) inhibit normal forward growth of mx (with use of headgear)