Fixed functional appliances in Orthodontics

2. Introduction
 The first fixed functional appliance was used as early
as 1905 by Emil Herbst.
 It was reintroduced by Hans Pancherz in 1979,who
popularized its use.
 These appliances are now used in both compliant and
non compliant patients for their enhanced
effectiveness in saggital correction of malocclusion in
a relatively short duration.

3. Classification
Rigid fixed functional
 -Herbst appliance
 -Mandibular anterior repositioning appliance.
 (MARA)
 Mandibular Protraction Appliance (MPA)
 Magnetic telescopic appliance,Ritto appliance.

4. Flexible fixed functional appliances
 -Jasper jumper
 -Adjustable bite corrector
 -Klasper super king

5. Hybrid fixed functional
 -Eureka spring
 -Twin force bite corrector
 -Forsus

7. Advantages
 Generate continuous stimuli for mandibular growth
without any break.
 They are relatively smaller in size therefore permit
better adaptation to functions like
mastication,swallowing,speech and respiration.

8.  Fixed functional appliances treat class II malocclusion
successfully in a shorter time span.
 Less patient cooperation is needed as it is a fixed
appliance
 It can be used successfully in patients who are at the
end of their growth.

12.  The appliance can be compared to an artificial joint
working between the maxilla and the mandible.
 A bilateral telescopic mechanism keeps the mandible
mechanically in continuous anterior position.
 The device consists of a tube into which the plunger
fits.

13.  The tube is fixed to the distal end of the maxillary
molars while the rod is fixed to the lower first
premolars.

20. Types
 Banded Herbst; Upper and lower first premolars and
first molars are banded. The tubes are fixed to pivots
soldered to the disto-buccal aspect of the first molar
bands. The shafts or rods are fixed to pivots soldered to
the lower first premolar bands.

21.  Bonded Herbst;The bonded type of Herbst appliance
is a wire reinforced acrylic splint that covers the
occlusal and part of the buccal and lingual surfaces of
all teeth except the anteriors.

22. Disadvantages
 Like any other functional appliances it requires patient
co-operation as initial discomfort is usually present.
 It can cause minor functional disturbances in the
masticatory system which are temporary and gradually
disappear.

23.  Risk for the development of dual bite.
 Repeated breakage.
 Plaque accumulation and enamel decalcification
occur, especially in splint type appliance.

24. Clinical manipulation
 First few days signs of muscle pain in and around jaw
muscles and TMJ do appear.
 Rapid changes in occlusion within in 6-9 months,
seen, showing correction of Class II malocclusion to
Class I occlusion.
 The appliance is removed and second phase of
treatment is started with fixed appliance therapy.

25. Jasper jumper
 Rigidity of the Herbst appliance restricts lateral
movement of the mandible. In an attempt to overcome
these problems, Jasper(1987) developed a new, flexible
pushing device. This appliance produces both sagittal
and intrusive forces, as does the Herbst bite jumping
mechanism, and also affords the patient more freedom
of mandibular movement.

26. Parts of the appliance
 Force module. The force module, analogous to the
tube and plunger of the Herbst bite jumping
mechanism, is flexible. The force module is
constructed of a stainless steel coil or spring attached
at both ends to stainless steel end caps in which holes
have been drilled in the flanges to accommodate the
anchor unit.

28.  The module is surrounded by an opaque polyurethane
covering for hygiene and comfort.
 The modules are available in seven lengths ranging
from 26 to 38mm.
 Force delivered is about 8 ounce or 250 gms of force.

29.  Attachment: The force module is attached posterior to
the maxillary arch by a ball pin attached through the
distal attachment of the force module.The ball pin
passes anteriorly through the face bow tube on the
first molar tube and cinched forward to activate the
module.

30. Transpalatal arch is combined with fixed appliance to
enhance maxillary anchorage.
Lower lingual arch is combined with fixed appliance
to enhance the mandibular anchorage.

31. Differences from Herbst
 The amount of force applied by the modules is more
easily controlled by the clinician.
 The flexibility of the force module has been shown to
increase patient comfort because of greater lateral and
sagittal movements possible.

32.  The force module curves away from the dental dental
arches in its activated position, making mastication
and oral hygiene procedures easier to perform.
 It can be added to existing fixed appliance at virtually
any point after arch preparation.

33. Disadvantages
 Breakage
 Unwanted tooth movement.

34. Instructions
 Not to chew on the appliance or perform movements
requiring wide opening of the mouth.
 Strict dietary controls are mandatory.

35. Thank you