MYOFUNCTIONAL APPLIANCES

FORM follows FUNCTION
INTRODUCTION-

• Myofunctional Appliances-Removable or fixed orthodontic appliances which use forces generated by the stretching muscle,fascia and/or periodontium to alter skeletal and dental relationships.
• They are passive appliances.
• How they work-These appliances use the natural forces generated by the stretched muscles.The increased muscle activity act as a stimulus for mandibular growth.
• All functional appliances are made up of following components-

1. BITE PLANES
2. SHIELDS
3. WORKING BITE
4. WIRE COMPONENTS

• BITE PLANES- 

*Types- Anterior/Posterior
              Flat/Inclined

*Anterior Bite block are helpful in opening of bite.They cause selective eruption of                                                        posterior segment of teeth.They can also be used to cease the supra eruption of anteriors.They can also be used to tip the anteriors.

*Posterior Bite Block are helpful in correcting anterior cross bite cases as they lift the bite up and eliminates the hindrance caused by mandibular teeth in the growth of maxilla and maxillary incisors.

*Anterior Inclined planes can be used to give a guiding plane for the labio lingual eruption of incisors or bucco lingual deflection of molars.

• SHIELDS-Vestibular shields/oral screens/lip pads are important in eliminating the undesired muscular forces (Like that of cheeks,lips etc),that impede the growth of jaws and causes favorable forces to act on jaws that can add to there growth .

        Shield also stretches the muscles causes underlying periosteal pull,which in turn causes bone growth in     desired direction.

These shield can also be used to prohibit various oral habits like mouth breathing,thumb sucking etc.

•  WORKING BITE-All functional Appliances are Constructed to a Construction or working bite registration.This registration is the one which is desired by the dentist or which is said to be the perfect occlusion for the patient.

       Construction Bites are taken at a Vertical Dimension.For a vertical grower the vertical dimension of construction Bite is kept more and for a horizontal grower its kept less.

• Some Important Points- 

1. Myofunctional Appliances can only be used only in growing patients.
2. Myofunctional Appliances are most favorably used in cases of Class II div 1 cases,having retrognathic mandible.
3. An ideal case for functional appliances is the one which is devoid of gross irregularities like crowding,rotations etc.
4. Most functional appliances causes upper anteriors to tip palatally and lower anteriors to tip bucally
5. Functional appliances causes condylar growth in upward and backward direction,leading a downward and forward growth of mandible.
6. Myofunctional Appliances also remodel condylar fossa in forward and downward direction.
7. It should be remembered that as the lower jaw grows anteriorly,the lower posteriors move mesially and occlusaly ,leading to increase in lower anterior facial height.All myofunctional appliances causes an increase in lower anterior facial height.so they should be cautiously used in patients having excessive vertical dimensions,and if used they should be used after  giving posterior bite blocks that can control the vertical eruption of molars.
8. In the transverse direction,functional appliances can bring about expansion of jaws by incorporating screws
9. Most of the functional appliances need post treatment fixed appliance therapy for detailing occlusion.

• Types Of Myofunctional Appliances-

1. ACTIVATOR
2. BIONATOR
3. FRANKEL
4. HERBST 
5. JASPER JUMPER