16. Definition:
Removable or fixed orthodontic appliances which use
forces generated by the stretching of muscles, fascia and
/ or Peridontium to alter skeletal and dental
relationships.
19. “If compensatory, adaptive lip and
tongue function could exacerbate
excessive over-jet in class II-type
malocclusions and if abnormal
swallowing and prolonged finger-
sucking habits could create anterior
open-bite and narrow maxillary arches,
could not the same muscles be used to
correct these and other problem????”
20. Background
Functional appliances are conceptually based on
Moss’ functional matrix theory
Functional matrix theory proposes that functional
matrices, tissues like muscles and glands influence
skeletal units such as jaw bones and ultimately
control their growth
21. The appliances used to improve functional relationship of dento-facial
structures by eliminating unfavorable developmental factors and
improving the neuromuscular environment enveloping the developing
occlusion
22. Function
Muscular Action
Effect on dento-alveolar
development
23. What they do…..?
Alter the neuromuscular environment of oro-facial region to improve
occlusal development and/or craniofacial skeletal growth
Utilize muscle forces to effect bony and dental changes
Disarticulate the teeth
Encourage new mandibular position
Require a tight lip seal during swallowing
Selectively alter the eruptive path of teeth
25. When???
Functional appliance treatment should be started before
the pubertal growth spurt
This is the time when the mandible may exhibit
increased growth which may be influenced
Duration---------------------------10-12 hours a day
These appliances should be worn at night-time as this is
when growth takes place
26. INDICATIONS
1. Growing ages (Mixed dentition and/or early permanent dentition)
2. Skeletal Considerations (Sagital correction of class II &III)
Skeletal Class II with Short mandible
a) Class II division 1
b) Class II division 2 (Convert div 2 to div 1)
1. Vertical Considerations
a) Normal to low angle cases
2. Dental Considerations
a) Local irregularity & rotation of incisors especially upper incisors
b) Crowding or dental compensation (Pre-functional Orthodontics
require
3. Open bite/ deep bite correction
4. Cross bite correction
5. To correct mal-forming dysfunction
27. CONTRAINDICATIONS
1. Children with neuromuscular disorders
a. Poliomyelitis
b. Cerebral palsy
2. Compliance
3. Hyperdivegent faces
4. Unfavorable growth
5. Protruded lower incisors
6. Severe crowding
7. Age
28. Treatment Principles
Force Application: Compressive stress and strain act
on the structures involved resulting in primary
alteration in form and secondary adaptation in
function e.g all removable appliances
Force Elimination: Abnormal and destructive
environmental influences are eliminated to allow
optimum development
like lip bumpers and frankel buccal sheilds
29. Mode of Action
Functional Appliances influence facial skeleton through
condylar and sutural areas.
Goal is to
Use the functional stimulus of oro-facial muscles
, channeling this stimulus to the jaws, condyles and teeth to
bring the change.
Purely functional and intermittent forces
30. Limitations
Adult Age(Ineffective in adults)
High Angle Cases(Increases vertical height of patient)
Compliance
Precise detailing of tooth position not possible
Crowding (Cases with ALD are difficult to manage)
Precise correction of Incisor inclination not possible
Increased lower incisor inclination (They tend to increase lower incisor
inclination & thus proper Sagital correction may not be possible if not properly
managed)
31. Functional appliances if used
properly & at right time then
they help in improving the
profile and eliminating the need
for Orthognathic Surgery
33. Active appliances reposition the mandible so that the
condyle is forced out of the glenoid fossa and this in turn is
thought to stimulate the posterior/superior growth of the
condyle.
Passive appliances act by repositioning the musculature
associated with the mandible so that the jaw bone itself
responds by growing to the new equilibrium position
37. Simple functional appliances
Can be used for both mand and
maxilla
Uses the muscular force from
upper or lower lip to provide distal
Lip bumper
force specially to molars
In lower arch headgear is less
acceptable so lip bumper is useful
Remove soft tissues forces from
labial aspect
Result increased lower incisor
inclination by influence of tongue
This can be reduced by placing it
as low as possible in labial sulcus
so that upper part of lip is in
contact with teeth
38. Simple functional appliances
Oral screens
Forerunner of functional
regulator
Consists of vestibular shields
which holds the lip away from all
teeth except upper incisors b/c
pressure from lips is transferred
to U I and acts to move them
palatally
Can be used in mixed dentition
and aids patient with digit
sucking
40. TYPES
MYOTONIC
Depend upon displacement of mandible in AP and vertical
plane. e.g Activators
MYODYNAMIC
Not only translate the mandible AP & vertically but also
attempt to utilize and translate muscular movements e.g
Bimler appliance
47. Andresen Activator Viggo Andersen
Mono-block
As upper and lower plates appear joined together
Activator
Norwegian appliance
48. Modified Andresen–Häupl-type activator
Class II cases Div I
For better control of lower incisor inclination,
the lower incisors are covered with acrylic,
which is relieved on the lingual surface
Correct overjet, overbite and molar relationship
during active growth
Labial bow to prevent incisors proclination
Maximum extension of lower lingual flanges in order to
redistribute the force on mucoperiostium of mandible
Coffin spring instead of palatal plate
Canine loops ----- screening loops of bionator and
buccal shields of FR.
49. Limitations
Difficulty in speech
Needs removal during eating
Arch expansion cannot be carried out
simultaneously
50. Andresen
Labial view of the Andresen appliance. The picture shows labial Bow in
0.8mm S.S wire with tubing and lower incisal capping.
55. Dr. Rolf Frankel
Passive functional appliance
Essentially tissue borne
Appliance of choice in class II due to mandibular retrusion.
FRANKEL APPLIANCE
Used in early mix dentition.
Has direct effect on neuromuscular system.
FRANKEL CORRECTOR
Causes anterior advancement of mandible and increase in LAFH.
Expands dental arches.
FUNCTIONAL REGULATOR
56. FUNCTIONAL REGULATOR
Oral vestibule is used as operational basis for the
treatment of dentoalveolar discrepancies.
It combines the principles of Anderson’s appliance
and oral screen.
Mode of action depends upon the relieving and
lifting the pressure on teeth from lips and
cheeks, so that the jaws can be allowed to grow and
the teeth can be guided to move into new more
favorable position.
57. Frankel
Appliance
The wire assembly anchors the appliance on
the maxillary arch at the mesial embrasure of
the of first molar.
59. FUNCTIONAL REGULATOR
FR I
a. Class I
b. Class II div 1 <5mm
c. Class II div 1 >7mm
FR II Class II div 2
FR III Class III
FR IV Open bite & mild bimax
60. FUNCTIONAL REGULATOR
FR I
a. Class I
It is mainly used to treat cases of Class I
malocclusion with minor to moderate crowding
or arrested development of dental bases.
It can also be used in class I malocclusion with
deep bite.
61. FR I Appliance
The components include:
Upper
• Palatal wire 6 / 6 in 0.9mm S.S wire.
• Canine wires 3 / 3 in 0.9mm S.S
wire.
• Labial Bow 2 / 2 in 0.9mm S.S wire.
Lower
• Lip Pads and Joining wires in 0.9mm
S.S wire.
• Hanger wires 5 / 5 in 0.9mm S.S
Labial view wire.
• Lingual Pusher Springs 3 / 3 in
0.7mm S.S wire.
66. FUNCTIONAL REGULATOR
FR I
b. Class II div 1 where over-jet is <5mm
c. Class II div 1 where the over-jet is >7mm
67.
68.
69. FUNCTIONAL REGULATOR
FR II Class II div 2
Prior to the functional therapy the incisor need to be
aligned
70. FR II Appliance
1. Flexible Appliance
2. The lingual and labial segments in lower portion encourage holding the mandible in a postured
position to alter the lip behavior.
3. By retraining the facial muscles & muscles of mastication to occupy new position.
4. The maxilla & mandible will be influenced to grow into corrected position.
5. Stretching of periosteum, osteoblastic activity & thus the bone formation.
Labial Bow Palatal Arch
Canine Clasps
Buccal Shields
Occlusal Rests
Labial Pads
71. FUNCTIONAL REGULATOR
FR III Class III
Mild Class III cases
The correction of class III Malocclusion is by dento-alveolar
means, not because of skeletal growth modification
72.
73. Registration of Bite
Varies with the type used.
Move mandible forward by 4 – 6 mm.
Or edge to edge contact of incisors
2.5 to 3.5 occlusal clearance.
Correction of sagittal discrepancy in 2 or 3 stages.
3 dimensional effect of FR
74. Bionator
1.Light Appliance
2.Better Compliance
3.Full Time Wear
Timing for Bionator Therapy
Effective and stable when it is initiated immediately before the pubertal growth
spurt. Optimal timing to start treatment with the Bionator is when a concavity is
evident at the lower borders of both the second and the third cervical vertebrae
(CVMS II).
In the long term, the amount of significant supplementary elongation of the
mandible in subjects treated with the Bionator during the pubertal growth spurt
is 5.1 mm more than that in untreated subjects with class-II malocclusion.
Significant increments in mandibular ramus height and for a significantly more
backward direction of condylar growth.
75. • Used in mix dentition.
• Major indication is in extremely deep
bite.
• Used to bring mandible in forward
position and to increase LAFH by
eruption of posterior teeth…California
Bionator.
• Can be used to close bite and
maintaining bite.
• Protusion springs may be used in class
II div2
76. Labial Bow
Bionator
Facets in the acrylic
which accepts maxillary
& mandibular teeth &
hold them in postured
position
Palatal spring
(Reverse coffin
spring)
Lingual horseshoe of acrylic
77. Twin Block
Indications
Class II div 1
Distal molar and canine relationship of at least half premolar
width
Overjet more than or equal to 5mm
Protrusion of maxillary incisors
Class II skelatal type ANB≥ 4
Occlusal development ..late mixed dentition or early
permanenet dentition
Normal & low angle cases
78.
79. Effects of twin block
Skeletal effects: mandibular length increses,during 1 yr, restrains
maxilla
Dentoalveolar change: upper incisors tip back
Lower incisors move forward
Overjet reduction.,.(correction achieved by skelatal and dentoalveolar
reduction
Correction of buccal segment achieved by combination of distal movement
of upper molars &forward movement lower molars
ANB reduction
Increased vertical dimensions..(inc lower facial height)mandibular plane
angle increases
Reduction of facial convexity
85. • Fixed functional.
• should be used in permanent
dentition.
• Easily tolerated by the patient.
• Should be changed after some time .
86. Fixed Functional Appliances
Advantages
Continuous stimulus for mandibular growth (24 hr use)
They are smaller in size permitting better adaptation to functions such as a
mastication, swallowing, speech and breathing.
Non-compliance Class II devices, which are able to treat Class II malocclusions
successfully,
while reducing the need for patient co-operation and overall treatment time.
Allows greater control by the orthodontist.
Disadvantages
Application of force is transmitted directly to the teeth through a support system,
the main disadvantage that may be encountered is dental movement that takes
place during treatment
87.
88. APPLIANCE DISCRIPTION
Can be compared to the artificial
joint between maxilla & mandible.
A bilateral telescopic mechanism
keeps the mandible in continuous
anterior position.
Appliance consists of a tube to which
plunger fits. Tube is fixed to the distal
end of maxillary molars & rod into
the lower first premolars.
89. Herbst Appliance
The Herbst appliance consists of two tubes, two plungers, axles and screws
Type I is characterized by a fixing system to the crowns or bands through the use
of screws.
It is necessary to weld the axles to the bands or crowns and then fix the tubes and
plungers with the screws
Type II has a fixing system that fits directly onto the archwires through the use of
screws
Disadvantage is the fracture of archwires
Type III is for anchorage
Type IV has a fixation system with a ball attachment, which allows greater
flexibility and freedom of mandibular movement.
Disadvantage in relation to other similar appliances is that it needs brakes to
stabilize the joint. The brakes are small and sometime difficult to fit. When a
fracture occurs or a brake is lost, the appliance comes loose
93. Indications
of FFFA
Class I (An anchorage reinforcement)
Class II division 1 and 2
Class III malocclusions
Molar distalization
Midline discrepancy
94. Flexible Fixed Functional Appliances
Inter-maxillary torsion coils, or fixed springs.
Advantages
Elasticity
Flexibility
Allow great freedom of movement of the mandible
Lateral movements can be carried out with ease
Disadvantages
Fractures can occur both in the appliance itself (mainly in areas that have more acute angles) and in the
support system (mainly in the lower arch)
If on one hand flexibility is an advantage, on the other hand it does tend to produce fatigue in the springs
Tendency of the patient to chew on the appliance, possibly contributing to breakage or damage.
It is not possible for the patient to completely open his mouth, depending on the way the system is fixed
onto the lower arch, good opening can be achieved.
Expansive & replacement of broken parts adds cost
Inventory
Unhygienic but covering of springs make them hygienic
95. Mechanism of Action
FFFAs allow the patient to close in centric relation
When the patient closes in centric relation, the contour of the bow should
be significantly increased
By slightly overactivating the appliance in centric relation, the patient will
automatically position the mandible forward. This is a natural response to
decrease the force module and alleviate discomfort.
96. Clinical Relevance
In brachyfacial cases, due to their strong musculature, it is necessary to use more force
(greater activation) than in dolicofacial cases.
If the patient has large cusps with good intercuspation, it will be necessary to exert greater
activation on the spring.
Greater force for orthopedic effects while lesser for dento-alveolar movements
To maximize the dentoalveolar movements in the upper arch and minimize any loss of
anchorage in the lower, the upper archwire is not tied back.
It can be used to obtain maximum anchorage, holding upper molars back as the upper
incisors are retracted.
97. Unwanted Effects
Due to the intrusive force on the upper molars, a posterior open bite is common
as well as posterior expansion due to the deflected force module.
Tendency for the lower molar to rotate mesiobuccally, causing a mild posterior
crossbite especially when the second molars have not been banded
Proclination of lower incisors..
Not recommended in mixed dentition, especially late mixed dentition to avoid
unwanted dental movements.
98. Jasper Jumper
Intrusion and distalization of the upper molars, with occasional opening of the
posterior bite similar to that seen with a Herbst ppliance.
Some indication of condylar growth.
Anterior migration of the mandibular teeth through alveolar bone.
Intrusion of the lower incisors.
99. Advantage
comfortable because of its covering.
Disadvantages
The large inventory that must be kept,
the coating material may degrade
Fractures
100. Contd.
Canines can be retracted against
mandibular dentition.
As the force modules cause
asymmetric forces, it can be used
to treat dental asymmetries.
Causes mandibular advancement
and increase in LAFH.
Can be used in post surgical
stabilization of class II patients.
101. Indications.
Dental Class II malocclusion.
Skeletal Class II with maxillary excess as opposed to mandibular deficiency.
Deep bite with retroclined mandibular incisors.
Midline Correction
Contra-indications.
Cases predisposed to root resorption.
Dental and skeletal open bites.
Vertical growth with high mandibular plane angle and excess lower facial height.
Minimum buccal vestibular space.
102. Rigid Fixed Functional Appliances
RFFAs do not easily fracture but neither do they have elasticity or flexibility.
After fitting and activation they do not allow the patient to close in centric relation.
This means that the mandible is in a forward position 24 hours a day creating
greater stimulus for mandibular growth than with FFFAs.
Skeletal effects produced with this type of appliance are greater than with FFFAs
Mechanism of Action
Telescopic mechanism which encourages forward repositioning of the lower jaw as
the patient closes into occlusion
103. Indications.
Dental Class II malocclusion due to retrognathic mandible
Skeletal Class II mandibular deficiency.
Deep bite with retroclined mandibular incisors.
They can be used as an anterior repositioning splinting patient with TMJ disorders.
Residual growth can be utilized in post adolescent patients.
Can be used in mouth breathers.
Contra-indications.
Cases predisposed to root resorption.
Dental and skeletal open bites.
Vertical growth with high maxillomandibular plane angle and excess lower facial height.
105. The Flip-Lock Herbst Appliance
Reduced number of moving parts that can lead to breakage or failure.
Easy to use
Comfortable
Instead of a screw attachment, it has a ball-joint connector so it needs no
retaining springs.
Less chairside time activation
106. Bonded Herbst Appliance It is a wire reinfofced acrylic splint.
The pivots are fixed to the wire
framework at distobuucal aspect
High Angle Cases of the upper first molar mesial
aspect of lower first premolar.
Tube is fitted to the pivot in the
upper molars & shaft is fixed to
mandibular premolar region
107. BANDED HERBST
Upper & lower first premolar & first molars
are banded.the tubes are fixed to pivots
soldered to distobuccal aspect upper first
molars.
The shaft or rods are fixed to pivots soldered
to lower first premolar band.
109. Hybrid Functional Appliances
Hybrid appliances are specifically and individually tailored to exploit
the natural processes of growth and development.
These appliances blend several components designed to address
specific problems
113. Fixed Version Of RFA
• Dynamax Appliance
• Fixed Twin Block
• Magnetic Appliances
• Elastics
114. Fixed version of RFA
Clip-on Fixed Functional Appliance
Advantages of the Appliance
Patient co-operation is not required.
It works for 24 hours a day.
A full fixed appliance can be placed at the same time as the Class II correction is
being carried out.
Treatment time is short because of full time wear.
There is no transitional phase between functional phase and the fixed phase so
treatment time reduced.
Overlap of the functional and fixed phase further reduces treatment time.
It is less bulky than other functional appliances.
115. Fixed version of RFA
JO March 2001
Clip-on Fixed FA Occlusal blocks with lingual tube attachments
Inclined Planes
Occlusal blocks with palatal
tube attachments.
116. Disadvantages of the Appliance
Breakage of the Appliance
Construction of the Appliance
.
Oral Hygiene Problems
Airways Clearance
Clip-on Fixed Functional Appliance
The results showed that this appliance was effective in correcting
Class II malocclusion; the noncompliance rate was only 6%
118. Head Gears
Orthopedic appliance that control growth of facial
structures
Various designs.
Used with growing patients.
119. USES OF HEAD GEAR
CORRECTION OF SKELETAL CLASS II AND REDIRECTION OF GROWTH
;(excess growth of maxilla/deficient growth of mandible)
Head gear restrain the forward and downward growth of maxilla by holding
back the growth of upper jaw, allowing the lower jaw to catch up and thus
the correction of class II.
MOLAR DISTILIZATION.
head gear may be used to distalize maxillary molar to correct the
class II molar relation ship or to gain space for relief of crowding.
AS AN ANCHORAGE
In some situations ,to maintain the bite, the orthodontist will not
want the back teeth to come forward. The headgear serves to hold them
back to maintain anchorage.
120. USES OF HEAD GEAR
REINFORCEMENT OF ANCHORAGE.
head gear can be used to reinforce anchorage in high
anchorage cases.
MOLAR ROTATION.
can also be brought about with the inner bow of headgear.
CORRECTION OF SKELETAL CLASS III.
(deficient growth of maxilla/excess growth of mandible).; by
protraction or reverse pull head gear that causes the
anterior displacement of maxilla.
121. CORRECTION OF SKELETAL CLASS II AND REDIRECTION OF GROWTH
;(excess growth of maxilla/deficient growth of mandible)
122. CORRECTION OF SKELETAL CLASS II AND REDIRECTION OF GROWTH
;(excess growth of maxilla/deficient growth of mandible)
131. BIOMECHANICS OF HEADGEAR
The relation ship of line of action of force to the
center of resistance of maxilla or first molar
determines whether translation (bodily )or rotation
(tipping) takes place.
When a force does not pass through the center of
resistance of the maxilla/molar, A moment is
produced.
The direction of line of force can be changed by
adjusting the length and position of outer bow.
132.
133. High Pull Head Gear
Bodily movement of molar
(no tipping) when line of
force is passing through the
center of resistance of
molar.
Both backward and upward
movement of molar.
When line of force is above
CR --- mesial tip of crown and
distal tip of root.
When line of force is below
CR --- mesial tip of root and
distal tip of crown.
134. Low Pull/Cervical Head Gear
Bodily movement of molar (no
tipping) when line of force is
passing through the center of
resistance of molar, as determined
by the outer bow length and
position
Both backward and downward
movements of molar.
When line of force is above CR ---
mesial tip of crown and distal tip of
root.
When line of force is below CR ---
mesial tip of root and distal tip
of crown.
The outer bow is always longer
than that used in High pull.
135. BIOMECHANICS OF HEAD GEAR
Similar considerations
apply to maxilla. Unless
the line of force is
through the center of
resistance, rotation of
maxilla occurs.
Control of line of force is
easier when face bow
inserted into the splint
covering all teeth.
With all teeth splinted; it
is possible to consider the
maxilla as a unit and to
relate the line of force to
the center of resistance of
maxilla.
136. RULE TO CHECK WHETHER THE LINE OF FORCE IS THROUGH THE
CENTER OF RESISTANCE IN HIGH PULL AND CERVICAL PULL
HEADGEAR
In order to determine the proper position of
outer bow. Use index finger to apply
pressure in direction of head gear selected.
A)In case of high pull headgear we move
index finger below the outer bow, pushing
up and back. As the finger is moved on the
outer bow applying force. The bow will move
up between the lips.
B)In case of cervical pull headgear we move
index finger above the outer bow, pushing
down and back. As the finger is moved on
the outer bow applying force. The bow will
move down between the lips.
137. BIOMECHANICS OF HEADGEAR
When the bow moves up, the roots of
maxillary first molar will move distally.
. When the bow moves down, the roots
of maxillary first molar will move
mesially and crown distally.
. When the bow does not move. The
force is through the center of
resistance of the maxillary first molar
and molar will move bodily and not
rotate.
138. BIOMECHANICS OF HEAD GEAR
EFFECT OF THE LENGTH OF OUTER BOW.
The longer outer bow bend up and shorter bow
bend down could produce the same line of force
through the center of resistance of molar.
139. High Pull Head Gear
Derives anchorage from parietal region. It
produces intrusion and distalization of teeth.
INDICATIONS.
Open bite cases.
High mandibular plane angle.
Long face cases with an increase in lower
anterior facial height.
High pull headgear can be used as.
HIGH PULL HEADGEAR TO MOLARS.
HIGH PULL HEADGEAR TO MAXILLARY
SPLINT
HIGH PULL HEADGEAR TO FUNCTIONAL
APPLIANCE.
140. CERVICAL HEAD GEAR
The anchor unit in this head gear is
nape of neck. It causes extrusion
and distalization of molars along
with distal movement of maxilla.
Indications:
short face,class II
Anchorage conservation.
early treatment of classII
141. Combination pull Headgear
Derives anchorage from
at least two regions ; the
neck and occiput. It
causes distal and slight
superior force on maxilla
and dentition.
142. Protraction head gear.
The rationale for protraction headgear is to apply heavy force
on the mid face in order to advance the maxilla anteriorly.
In this type inner bow is bent to achieve distal insertion ,outer
bow is modified to make hook in premolar region for elastic
attachment.
The center of resistance of mid face is difficult to locate but
most studies shows it 5-10mm below the orbit.
143. Protraction head gear.
A line of force closer to
center of resistance of
mid face will deliver a
translatory force and
line of force closer to
occlusal plane has
rotational force.
144. Petit Face Mask
For the protraction of
maxilla and maxillary
dentoalveolar segments.
developing Class III
pattern.
Cleft lip and palate
patients.
Extra-oral elastics
(heavy)
145. Asymmetric head gear.
Asymmetic force is
achieved with a head
gear by using an
asymmetric outer
bow,can be useful in
regaining bilateral but
asymmetric lost space.
146. Time, Duration and Force of Headgear
Therapy.
FORCE. 500 TO 700gm(orthopedic )150-
200gm(orthodontic force).
DURATION 12 -14hrs /Day, emphasis on wearing it from
early morning.
Treatment Duration. 12 TO 18 Months.
147. TREATMENT EFFECTS
SKELETAL EFFECTS
Frontomaxillary,zygomaticotemporal,zygomaticomaxil
lary n pterygopalatine r most imp growth sites for
development of maxilla.
head gears act by compressing the sutures thus
restricting the normal downward n fowad growth of
maxilla.
DENTAL EFFECTS
Distalization of molars.
Extrusion and intrusion of molars
148. SIDE EFFECTS OF HEAD GEAR
Compensatory erruption of max And mand molars but
can be controlled by fixed lingual arch.
Distal tipping of max molars.
Increased facial height.
