Myofunctional Appliances

Question 1

TWIN BLOCK APPLIANCE

Answer 1

Advantages of twin block
1. It’s mechanism of action is very similar to natural dentition
2. Allows free mandibular movement [ pt can eat and speak]
3. Less bulky
4. Better pt compliance
5. Excellent retention and easily tolerated
6. Appearance is noticeably improved after insertion

Indications Indications
1. Class II div 1 or 2
2. Growing pt
3. Pt is in late mixed dentition
4. IDEALLY [ but not necessary] – well aligned arches
5. Mild to moderate class II skeletal pattern
6. Retrognathic mandible
7. Overjet of 10 mm or less
8. Normal to deep overbite
9. Improved facial esthetics once the mandible is brought forward

Question 2

Vestibular screen

Answer 2

Indications
– Mouth breathing
– Thumb sucking, tongue thrust habits .
– Mild disto-occlusions
-Anterior proclination

Modifications:
– Hotz modification: oral screen + metal
ring. For performing muscle exercises
– Additional screen on lingual aspect of teeth – for tongue thrust
– Fabrication of screen with holes for mouth breathing patients

Question 3

Lip bumper

Answer 3

Indications
– Lip sucking
– Hyperactive mentalis
– Augment anchorage
– Distalization of first molars
– Space regaining

Question 4

Activator

Answer 4

Results in stretching of elevator muscles of mastication

Generates kinetic energy which causes:

• Prevention of further forward growth of maxillary dentoalveolar process

• Distal movement of maxillary process

•Reciprocal forward movement of mandible

Question 5

Bionater

Answer 5

3 types :

a. Standard appliance: Used for the treatment of Class II div 1 and Class I malocclusions with narrow dental arch

b. Class III appliance : Used in mandibular prognathism

c. Open bite appliance : open bite cases

Question 6

Frankel

Answer 6

Good to use when soft tissues contribute greatly to the malocclusion

Used in class II malocclusion or class III malocclusion

The acrylic shields/screens are used to push the lower lip outward and increase bone deposition in the mandible

Used to control the tongue that could be causing the over jet + it contacts teeth to resist maxillary growth [but still soft tissue borne]

Advantage :
– It is fixed and you don’t need Pt compliance to wear it , but the Pt has to look after it to prevent it from breaking
– Continuous force
– Treatment duration is short
– Can used in mouth breathing habit

Disadvantages
– Not commonly used because of the high % of breaking

Question 7

Herbst

Answer 7

Indications

– Class II malocclusion due to retrognathic mandible
– Anterior repositioning splint in patients with TMJ
disorders
– Post adolescent patients
– Mouth breathers
– Uncooperative patients