LRM Activator Types Of Orthodontic Appliances Improve Tonicity

• No side effects of mechanotherapy
• Less chair side time
• Easy to maintain oral hygiene Acceptable can be worn during night

DISADVANTAGES

• Not useful in adults where active growth completed
• Patient cooperation n wearing appliance important
• Not possible to correct rotation ,crowding etc
• Tendency to increase lower facial height therefore contraindicated in patients with backward rotating mandible 

Classification of functional appliances

•  Tooth borne active appliance eg activator ,bionator tooth borne passive appliance eg springs ,screws.
• Tissue borne passive appliance eg frankel functional appliance

• myotonic appliance
• myodynamic appliance

Removable functional appliance eg activator and bionator 

Fixed functional appliance

group 1 appliances --eg inclined plane ,oral screen

group 2 appliances --eg activator ,bionator

group 3 appliances --eg frankel appliance 

TREATMENT PRINCIPLES FORCE APPLICATION

Compressive stress and strain act on the structures involved and result in a primary alteration in form with a secondary adaptation in function

FORCE ELIMINATION

The principle involves the elimination of abnormal and restrictive environmental influences on the dentition thereby allowing optimum development thus function is rehabilitated with a secondary change in form. these components produce skeletal and dentoalveolar changes by acting on the following

1. eruption

2. linguofacial muscle balance

3. mandibular repositioning 

Action of functional appliance

Functional appliance can produce following changes

1. Orthopedic changes

2. dentoalveolar changes

3. muscular changes orthopedic changes

Myofunctional appl are capable of accelerating growth in condylar region

They bring about remodelling of glenoid fossa

They can change direction of growth of the jaws dentoalveolar changes

They can bring about changes in sagittal ,transverse,and vrtical directions most MFA allow upper anteriors to tip labially

In tranverse direction they can bring about expansion of the dental arches by incorporating screws in them In vertical plane they allow selective eruption of teethmuscular changes

Functional appliance can improve tonicity of the oro facial musculature