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1. Evolution of FunctionalEvolution of Functional
AppliancesAppliances

2. BionatorBionator
Balters(1943)Balters(1943)
• The bulkiness of the activator and its limitationThe bulkiness of the activator and its limitation
to nighttime wear lead to the development ofto nighttime wear lead to the development of
Bionator which is a prototype of Muzy’sBionator which is a prototype of Muzy’s
appliance.appliance.
• Here the palate is free for propioceptive contactHere the palate is free for propioceptive contact
with the tongue and the buccinator wire loopswith the tongue and the buccinator wire loops
hold away potentially deforming muscle action.hold away potentially deforming muscle action.

4. • Skeleton of the activatorSkeleton of the activator
+ Modification of Robin’s thoughts+ Modification of Robin’s thoughts
• According to BaltersAccording to Balters
““ The equilibrium between tongue andThe equilibrium between tongue and
cheeks, especially b/w tongue and lips incheeks, especially b/w tongue and lips in heightheight,,
breath and depth in an oral space of maximunbreath and depth in an oral space of maximun
size and optimal limits, providing functionalsize and optimal limits, providing functional
space, is essential for the natural health of thespace, is essential for the natural health of the
dental arches and their relation to each other ”dental arches and their relation to each other ”

5. • Abnormal position of the tongue led toAbnormal position of the tongue led to
development of malocclusions :development of malocclusions :
- Class II : Posterior displacement- Class II : Posterior displacement
- Class III : low anterior displacement :- Class III : low anterior displacement :
- Narrow arches and crowding : low outward- Narrow arches and crowding : low outward
pressurepressure
- Open bite : hyperactivity and forward posture- Open bite : hyperactivity and forward posture

6. • He was in support ofHe was in support of
- Function and Form concept : Van der klaauw- Function and Form concept : Van der klaauw
- Functional Matrix theory : Melvin Moss- Functional Matrix theory : Melvin Moss
• Aims of RxAims of Rx ::
1.1. Accomplish lip closure and establish contact b/wAccomplish lip closure and establish contact b/w
back of the tongue and soft palateback of the tongue and soft palate
2.2. Enlarge oral spaceEnlarge oral space
3.3. Incisors in edge to edgeIncisors in edge to edge
4.4. Elongation of the mandibleElongation of the mandible
5.5. Leading to an improved relationship b/w the jaws,Leading to an improved relationship b/w the jaws,
tongue, dentition and soft tissuestongue, dentition and soft tissues

7. Bionator- typesBionator- types
• Standard applianceStandard appliance ::

8. • Open bite applianceOpen bite appliance

9. • Reversed/Cl III ApplianceReversed/Cl III Appliance

10. Bimler Appliance (1949)Bimler Appliance (1949)
• Also referred to as :Also referred to as :
- GebissformerGebissformer
- Oral adaptorOral adaptor
- Terminus technicusTerminus technicus
• Activator – only night time useActivator – only night time use
• Bimler aimed at using small appliances whichBimler aimed at using small appliances which
can be worn during the day time.can be worn during the day time.

11. • Basic applianceBasic appliance ::
- Labial arch wire : UpperLabial arch wire : Upper
archarch
- Lingual arch wire :Lingual arch wire :
Lower archLower arch
- Joined together by smallJoined together by small
acrylic wings palatalacrylic wings palatal
wings palatal to thewings palatal to the
upper buccal segments.upper buccal segments.

13. • Additional wire elementsAdditional wire elements
- U loopU loop
- SpringsSprings

14. • VariationsVariations
- Class A : class 2 div 1Class A : class 2 div 1

15. • Class B : Class 2 div 2Class B : Class 2 div 2

16. - Class C : Class 3Class C : Class 3

17. KinetorKinetor
( Hugo stockfish -1951 )( Hugo stockfish -1951 )
• Combination of ActiveCombination of Active
and Myo-functionaland Myo-functional
treatment methodstreatment methods
• Muscular forces derivedMuscular forces derived
from the mandibularfrom the mandibular
dislocation are joineddislocation are joined
with the active operationwith the active operation
of screws and springs.of screws and springs.

18. • As defined byAs defined by StockfishStockfish ::
““ The kinetor is a movable myofunctionalThe kinetor is a movable myofunctional
bimaxillary plate which on account of kineticbimaxillary plate which on account of kinetic
energy of the oro-facial system retains rheenergy of the oro-facial system retains rhe
impulses in a sagittal, vertical and transverseimpulses in a sagittal, vertical and transverse
directions which can then be utilised in thedirections which can then be utilised in the
posterior region via springs, screws and elasticposterior region via springs, screws and elastic
tubing b/w the upper and lower plates.”tubing b/w the upper and lower plates.”

20. Frankel’s Functional RegulatorFrankel’s Functional Regulator
( Rolf Frankel - 1960 )( Rolf Frankel - 1960 )
• Marked a new phase of development in the evolutionMarked a new phase of development in the evolution
of functional appliances.of functional appliances.
• Created “ A revolution in orthodontic appliances ”Created “ A revolution in orthodontic appliances ”
- Charles nord- Charles nord
• Frankel had a greater impact on American orthodonticsFrankel had a greater impact on American orthodontics
than any other proponent of functional appliances.than any other proponent of functional appliances.

21. • Conducted courses forConducted courses for ::
- AAOAAO
- G.V.Black Institute for continuing educationG.V.Black Institute for continuing education
- Ann Arbor Orthodontic study clubAnn Arbor Orthodontic study club
- Kenilworth research foundationKenilworth research foundation
- University of ChicagoUniversity of Chicago
- University of DetroitUniversity of Detroit

22. • Inspired by :Inspired by :
1.1. Therapeutic Goal :Therapeutic Goal : Robin, Anderson-HauplRobin, Anderson-Haupl
2.2. Dynamic functional orthopaedic approach :Dynamic functional orthopaedic approach : BimlerBimler
3.3. Use of additional wire elements :Use of additional wire elements : EshlerEshler
4.4. Elimination of damaging forces :Elimination of damaging forces : BaltersBalters
5.5. Broad based vestibular loops :Broad based vestibular loops : StockfishStockfish

23. Frankel philosophyFrankel philosophy::
• Potential restraining influence of the active muscle andPotential restraining influence of the active muscle and
tissue mass of the buccinator mechanism and thetissue mass of the buccinator mechanism and the
orbicularis oris complexorbicularis oris complex
• Artificial matrix allowing the muscles to exercise andArtificial matrix allowing the muscles to exercise and
adaptadapt

26. • Exercise device: stimulates normal function, eliminatingExercise device: stimulates normal function, eliminating
the lip trap, hyperactive mentalis, aberrant orbicularisthe lip trap, hyperactive mentalis, aberrant orbicularis
oris and buccinatororis and buccinator
• Negative pressure of the muscles during deglutition isNegative pressure of the muscles during deglutition is
preventedprevented
• Bodily buccal movement of posterior teethBodily buccal movement of posterior teeth
• Oral gymnastics: lip seal exercisesOral gymnastics: lip seal exercises

27. • Periosteal pull of buccal shields and lip padsPeriosteal pull of buccal shields and lip pads
increases bone activityincreases bone activity
• Stimulation of mid palatal suture growth lesserStimulation of mid palatal suture growth lesser
extent increasing bone apposition on theextent increasing bone apposition on the
external subperiosteal layer of maxillaexternal subperiosteal layer of maxilla
( Stutzmann et al 1983, Graber et al 1991)( Stutzmann et al 1983, Graber et al 1991)

29. Dental effectsDental effects::
• Appliance anchored to maxillary arch; allowsAppliance anchored to maxillary arch; allows
more downward and outward movement ofmore downward and outward movement of
upper teethupper teeth
• Lower posterior teeth are allowed to eruptLower posterior teeth are allowed to erupt
upward and forward; sagittal and verticalupward and forward; sagittal and vertical
correctioncorrection

30. • In 1984 Frankel reduced his appliance to 4In 1984 Frankel reduced his appliance to 4
basic types:basic types:
1.1. FR I : Class I / Class II Div IFR I : Class I / Class II Div I
2.2. FRII : Class II Div I/IIFRII : Class II Div I/II
3.3. FR III : Class IIIFR III : Class III
4.4. FR IV : Open bite / Bimaxillary protrusionsFR IV : Open bite / Bimaxillary protrusions

31. Twin block TheraphyTwin block Theraphy
( William J.Clark )( William J.Clark )
• Introduced in 1977 as a two-piece appliance resembling aIntroduced in 1977 as a two-piece appliance resembling a
Schwarz double plate and a split activator.Schwarz double plate and a split activator.
• Further reviewed by clark ( 1982, 1988, 1995 )Further reviewed by clark ( 1982, 1988, 1995 )
• Replacement of occlusal inclined planes by means of acrylicReplacement of occlusal inclined planes by means of acrylic
inclined planes on bite blocksinclined planes on bite blocks
• Guide mandible downward and forwardGuide mandible downward and forward
• Favorable propioceptive contacts of inclined planes.Favorable propioceptive contacts of inclined planes.
• Adaptation of the muscles of masticationAdaptation of the muscles of mastication

33. Advantages over other Functional appliancesAdvantages over other Functional appliances
1.1. Functional mechanism similar to natural dentition.Functional mechanism similar to natural dentition.
2.2. Occlusal inclined planes give greater freedom ofOcclusal inclined planes give greater freedom of
movement in anterior and lateral excursions.movement in anterior and lateral excursions.
3.3. Less interference with normal function.Less interference with normal function.
4.4. Improved appearance and function due to absence ofImproved appearance and function due to absence of
lip, cheek and tongue pads.lip, cheek and tongue pads.
5.5. Esthetically acceptable.Esthetically acceptable.
6.6. Can be worn 24 hrs.Can be worn 24 hrs.
7.7. Indepent control over upper and lower arch width.Indepent control over upper and lower arch width.

34. • OcclusalOcclusal bite blocks with inclined planesbite blocks with inclined planes
• Midline screws for expansionMidline screws for expansion
• Retention : Adams clasps Delta claspsRetention : Adams clasps Delta clasps
• Interdental clasps on lower incisorsInterdental clasps on lower incisors
• Labial bows on upper incisors : Continuous / splitLabial bows on upper incisors : Continuous / split
Active / PassiveActive / Passive
• Springs to move individual teethSprings to move individual teeth
• Provision for extraoral tractionProvision for extraoral traction
DesignDesign

38. Herbst ApplianceHerbst Appliance
( Herbst -1909 )( Herbst -1909 )
• First presented his fixed bite jumping device (First presented his fixed bite jumping device ( Scharnier )Scharnier )
–– International Dental Congress-BerlinInternational Dental Congress-Berlin..
• Mandible continuously placed in a protruded position.Mandible continuously placed in a protruded position.
• UsesUses : ( Herbst, Schwarz – 1934 ): ( Herbst, Schwarz – 1934 )
1.1. Cl II MO with Retrognathic mandibles.Cl II MO with Retrognathic mandibles.
2.2. To facilitate healing after mandibular ramus fractures.To facilitate healing after mandibular ramus fractures.
3.3. As artificial joint after surgical removal of condylar head.As artificial joint after surgical removal of condylar head.
4.4. TMJ problems – Clicking, Bruxism.TMJ problems – Clicking, Bruxism.

40. • Not well accepted and reintroduced by Pancherz( 1979)Not well accepted and reintroduced by Pancherz( 1979)
• IndicationsIndications : ( Pancherz ): ( Pancherz )
1.1. Cl II MO with Retrognathic mandibles.Cl II MO with Retrognathic mandibles.
2.2. Postadolescent patientsPostadolescent patients
3.3. Mouth breathersMouth breathers
4.4. Uncooperative patientsUncooperative patients
5.5. Patients who do not respond to removable functionalPatients who do not respond to removable functional
appliances.appliances.

41. • Since 1979 gained importance and led to theSince 1979 gained importance and led to the
development of various fixed functionaldevelopment of various fixed functional
appliances.appliances.

42. Combined Extraoral and FunctionalCombined Extraoral and Functional
AppliancesAppliances
• Class II div 1 with excessive vertical growthClass II div 1 with excessive vertical growth
• Unloading of the condyle by forward posture ofUnloading of the condyle by forward posture of
mandiblemandible
• Retardation of horizontal and vertical maxillaryRetardation of horizontal and vertical maxillary
growth by headgeargrowth by headgear

43. Varoius AppliancesVaroius Appliances
1.1. Spengeman (1967) - Hawley's retainerSpengeman (1967) - Hawley's retainer
2.2. Jacobson splint (1967) -Jacobson splint (1967) -
3.3. ACCO- Margolis (1976) - Hawley's retainerACCO- Margolis (1976) - Hawley's retainer
4.4. Verdon appliance - Modified activatorVerdon appliance - Modified activator
5.5. Stockli / Teuscher - Modified activatorStockli / Teuscher - Modified activator
6.6. Clark - Twin blockClark - Twin block
7.7. Stockfish - KinetorStockfish - Kinetor

44. Magnetic Functional SystemMagnetic Functional System
( Alexander D.Vardimon -1991 )( Alexander D.Vardimon -1991 )
• Rationale for introducing magnets in FA isRationale for introducing magnets in FA is
based on the necessity of decreasing thebased on the necessity of decreasing the
incidence of treatment failure associatedincidence of treatment failure associated
with conventional appliances.with conventional appliances.

45. Advantages of MagnetsAdvantages of Magnets
1.1. High force-to-volume ratioHigh force-to-volume ratio
2.2. Maximal force at short distancesMaximal force at short distances
3.3. 3-Dimensional orientation of magnetic force3-Dimensional orientation of magnetic force
4.4. No interruption of magnetic force by intermittentNo interruption of magnetic force by intermittent
mediamedia
5.5. No friction in attractive force configurationNo friction in attractive force configuration
6.6. No energy loss.No energy loss.

47. Etiology for treatment failureEtiology for treatment failure
1.1. Unfavourable skeletal growth patternUnfavourable skeletal growth pattern
2.2. Inadequate patient complianceInadequate patient compliance
3.3. Incompetent neuromuscular adaptationIncompetent neuromuscular adaptation
4.4. Default differential diagnosisDefault differential diagnosis

48. MODE OF ACTION OF FUNCTIONALMODE OF ACTION OF FUNCTIONAL
APPLIANCES AS EXPLAINED BY THEAPPLIANCES AS EXPLAINED BY THE
SERVOSYSTEMSERVOSYSTEM

49. Two Types of Functional AppliancesTwo Types of Functional Appliances
1. Activator, Postural hyperpropulsor, Frankel
appliance, Twin block, Bionator, Class II
Elastics(?)
2. Herren activator, LSU activator, Harvold-
Woodside activator, Extra oral traction on the
mandible.

50. • FIRST GROUP:
• Position mandible Increased activity
of Forward LPM and RDP
• LPM “helped to contract more” by
Functional appliances.

52. • Chondroblasts lost Increased
multiplication of
prechondroblasts
• Local control over multiplication of
prechondroblasts originates from chondroblastic
layer
- Stutzmann and Petrovic
(1982,1990)

54. Functional appliances
Increased activity of RDP
Increased nutrients and growth factors supplied
and inhibitors removed.
Increased mitoses and earlier hypertrophy of
chondroblasts.

55. Reduced negative feedback
signal reaching
prechondroblasts
Increased growth at the
condyle

56. Cytoplasmic junctions between skeletoblasts reduce.
Transmission of inhibitory factors reduce.
Increased mitotic rate and rate of differentiation into
prechondroblasts.

57. SECOND GROUP:
Position mandible forward , open in beyond rest
position.
No increase in activity of LPM
•Herren (1953)
•Auf der Maur (1978)
Yet there was an increase in growth

58. wo steps:
) While appliance is worn:-
Forward position
Reduction of length of LPM
New sensory engram
) While appliance is not worn:-
New sensory engram
Functioning in anterior position
Increased activity of RDP

59. Action of first group while appliance is worn
Action of second while appliance is not worn
group

60. CLINICAL IMPLICATIONSCLINICAL IMPLICATIONS
1) Principle of optimality of function :-
Less relapse tendency if post orthodontic
treatment muscular activity produces a lower
deviation signal.

61. 2) Removal of functional appliance – when growth
is complete.
3) If removed when growth not complete – Proper
intercuspation.

62. 4) Understanding of when, and for how long a
particular functional appliance should be worn.
First group – Full time
Second group – Part time

63. 5) Proper functioning of LPM and RDP important for
growth – Proper parent counseling.
6) Sensory engram poorly developed in younger
children.
7) Utilization of high hormonal activity at puberty.