functional appliances

Question 1

What is a functional appliance? And when are they most commonly used?

Answer 1

functional appliances use forces generated by the orofacial soft tissues to move teeth

Commonly used in class2/1

Question 2

How do they work?

Answer 2

they posture the mandible away from the rest position which causes the tissues to be stretched

Question 3

How can we classify functional appliances?

Answer 3

by the mode of action

Question 4

What are the two types of FA based upon the mode of action?

Answer 4

myodynamic

myotonic

Question 5

How do myodynamic FA work?

Answer 5

they generate forces by stimulatig MoM

Question 6

How do myotonic appliances work?

Answer 6

elastic recoil withing the stretched soft tisssues

Question 7

functional appliances work in three main ways?

Answer 7

Dentoalveolar
skeletal
soft tissue

Question 8

What is the major mechanism by which FA work?

Answer 8

dentoalveolar

stretched soft tissues apply forces to teeth

Question 9

What are the dentoalveolar effects in the upper arch?

Answer 9

retraction of upper incsors
distal movement of upper buccal segment teeth
Expansion of upper arch

Question 10

What is the dentoalveolar effect on the lower arch?

Answer 10

proclinaion of lower incisors
overbite reduction by using anterior bite plane
mesial movement over lower buccal segment teeth this is bcause as they erupt they move mesially

Question 11

What are the skeletal effects?

Answer 11

mandbibular growth is enhanced by 1mm

maxilliary growth inhibited by 1mm

Question 12

What are the vews regarding skeletal effects of functional appliances?

Answer 12

a change in the direction of growth
FA only work during the period of wearing but not much effect longterm
a chage in the position in the glenod fossa
promotes mandib growth than wold otherwise occur

Least to most controversial

Question 13

Who propsed the soft tissue effects of functional appliances?

Answer 13

the soft tissue theory has been propsed by frankel

Question 14

What is the bases of the theory of the soft tissue effects? And how well accepted is this?

Answer 14

functional matrix theory of moss

Not well accepted

Question 15

WHat are the soft tissue effects?

Answer 15

lip exercises and functional applainces can alter the posotion of the lips and cheeks, this will enable the teeth to move into their correct positions

Question 16

When are functonal applainces used?

Answer 16

growing patient since can influence growth more in a growing patient 
girls: 10-12
Boys: 12-14
Better tolerated in younger patient
Later mixed and early permanent

Question 17

What is the example of a myodynamic appliance?

Answer 17

clark twin block and bionator

Question 18

How does the clark twin block appliance work?

Answer 18

two part appliance
well tolerated
paeint can eat in it
it has two interlocking bite planes that posture the mandible forwards

Question 19

How does the bionator work

Answer 19

myodynamic
patient has to bite to keep it in position
no retentive components
single piece construction
Useful in mixed dentition

Question 20

What is an example of a myotonic appliance?

Answer 20

harvold appliance
it postures the mandible in a more vertical position rather than AP
not wel tolerated
useful in mixed dentition
No retentive components
Single piece constriction

Question 21

When would you use functional appliances?

Answer 21

Most common : class 2/1 with or without crowding on a moderate/severe class 2 skeletal base
class 2/2 on moderate or severe class 2 skeletal pattern:convert to class 2/1 first
Class 3 incisor but not common

Question 22

How do you make functional appliances?

Answer 22

upper and lower imps

need to record a postured wax bite when the patient is in a comfortable position and use a bite fork to help

Question 23

How much should the overjet reduce by?

Answer 23

on average 1mm/month

Question 24

What dental feature may appear wiht the use of functional appliances?

Answer 24

lateral open bites

Question 25

How does the frankel 2 appliance work?

Answer 25

Has buccal and labial acrylic shields which influence the soft tissues  
Single price construction 
Not retentive
Not well tolerated
Expensive and fragile
Mixed dentition

Question 26

How can you monitor treatment progress of functionals?

Answer 26

Speech should be normal
Does the appliance show signs of wear
Molar relationship should improve
Lateral open biter may develops

Question 27

Name 4 fixed functional appliances

Answer 27

Herbst
MARA
Dynamax
Advansnyc