Bionator-&-twin-block-20207311350180.pptx

1. BIONATOR & TWIN BLOCK
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2. BIONATOR
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3. BALTER’S BIONATOR(1943)
 The bulkiness of the activator and its
limitation to nighttime wear lead to the
development of Bionator which is a
prototype of Muzy’s appliance.
 Kantorowicz termed the bionator the
skeleton of an activator from which there
is nothing left but the naked embodiment
of Robins thoughts
 Here the palate is free for propioceptive
contact with the tongue and the
buccinator wire loops hold away
potentially deforming muscle action.
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Removable orthodontic appliances-T.M.Graber & B.Neumann
Dentofacial orthopaedics with functional appliances-Graber,Rakosi,Petrovic

4. BALTERS HYPOTHESIS
 Skeleton of the activator
+ Modification of Robin’s
thoughts
 According to Balters
“ The equilibrium between tongue and
cheeks, especially b/w tongue and lips in
height, breath and depth in an oral space of
maximun size and optimal limits, providing
functional space, is essential for the natural
health of the dental arches and their relation
to each other ”
Removable orthodontic appliances-T.M.Graber & B.Neumann
Dentofacial orthopaedics with functional appliances-Graber,Rakosi,Petrovic
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5.  Abnormal position of the tongue lead to
development of malocclusions :
- Class II : Posterior displacement
- Class III : low anterior displacement :
- Narrow arches and crowding : low outward
pressure
- Open bite : hyperactivity and forward
posture Removable orthodontic appliances-T.M.Graber & B.Neumann
Dentofacial orthopaedics with functional appliances-Graber,Rakosi,Petrovic
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6. TYPES OF BIONATOR
 There are three types of Bionator
1. Standard appliance
2. Class III appliance
3. Open bite appliance
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7. Standard Appliance
 This is used for the treatment of class II div1
and class I malocclusions having narrow
dental arches
 The standard appliance consists of a
relatively slender acrylic body fitted to the
lingual aspect of the mandibular arch and
part of the maxillary arch
 The acrylic extends up to the distal of the first
permanent molar
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8.  The maxillary plate covers only the
molars and the premolars with the
anterior region remaining uncovered
 The acrylic extends 2mm below the
gingival margin
 The inter-occlusal space of the buccal
teeth is filled with acrylic extending over
half of the occlusal surface of the teeth to
stabilize the appliance
 The wire components of the bionator are
the palatal arch or coffin spring and the
vestibular wire
Removable orthodontic appliances-T.M.Graber & B.Neumann
Dentofacial orthopaedics with functional appliances-Graber,Rakosi,Petrovic
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9.  The palatal arch is made of 1.2mm diameter
wire.
 It emerges opposite the middle of the first
premolars and follows the contour of the
palate forming a curve that reaches the distal
surface of first permanent molar.
 The palatal arch is kept 1mm away from the
mucosa.
 The vestibular wire is made up of 0.9mm
stainless steel wire.
 It emerges from the acrylic below the contact
point between the upper canines and
premolars. 9
Removable orthodontic appliances-T.M.Graber & B.Neumann
Dentofacial orthopaedics with functional appliances-
Graber,Rakosi,Petrovic

10. 10

11.  It rises vertically and is bend at right angles to g
distally along the middle of the upper premolar
crowns.
 Mesial to the molar, a rounded bend is made so
that the wire runs at the level of the lower papilla
up to the mandibular canine where it is bend to
reach the upper canines.
 It forms a mirror image on the opposite side.
 The vestibular wire is kept away from the surfac
of incisors by the thickness of a sheath of paper
 The lateral portions of the wire are sufficiently
away from the teeth to allow expansion of the
arch
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12. Class III Appliance
 It is also called reverse bionator.
 This is used in mandibular prognathism.
 The acrylic parts are similar to the
standard appliance .
 The palatal arch is placed in the opposite
direction so that the rounded arch is
placed anteriorly .
 The vestibular wire runs over the lower
incisors instead at terminating at the lower
canines .
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13. Class III Appliance
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14. Open Bite Appliance
 This is used in open bite cases.
 The palatal arch and the vestibular wires
are same as the standard appliance.
 The maxillary acrylic portion is modified so
that even the anterior area is covered.
 Its purpose is to prevent the tongue from
thrusting between the teeth as the tongue
is responsible in most cases for the open
bite.
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15. Palatal Bar
 The forward orientation of tongue is
accomplished by stimulating its dorsal
surface with the palatal bar so it has a
posterior curve.
 Open bite bionator also has posterior
directed palatal bar with the aim of moving
the tongue in more posterior position.
 In class three the tongue is stimulated to
remain in retracted position in its proper
functioning space it should contact anterior
portion of palate encouraging forward growth
in this area.
Removable orthodontic appliances-T.M.Graber & B.Neumann
Dentofacial orthopaedics with functional appliances-Graber,Rakosi,Petrovic
15

16. Construction bite
 In most cases an edge to edge bite is
desirable .
 No vertical allowances are made. Balters
reasoned that high construction bite will
impair tongue function and the patient could
actually acquire a tongue thrust habit.
 If the over jet is too much a step wise
advancement is preferred .
 This bite is known as Balters functional bite.
Removable orthodontic appliances-T.M.Graber & B.Neumann
Dentofacial orthopaedics with functional appliances-Graber,Rakosi,Petrovic
16

17. TERMINOLOGY USED IN TRIMMING THE
BIONATOR:
Articular plane
Loading area
Tooth bed
Nose
Ledge
Dentofacial orthopaedics with functional appliances-Graber,Rakosi,Petrovic
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18. ARTICULAR PLANE
Dentofacial orthopaedics with functional appliances-Graber,Rakosi,Petrovic
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19. Tooth Bed
Nose
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Dentofacial orthopaedics with functional appliances-
Graber,Rakosi,Petrovic

20. Ledge
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Dentofacial orthopaedics with functional appliances-Graber,Rakosi,Petrovic

21. ANCHORAGE OF THE
APPLIANCE
• Incisal margins of the lower incisors--cap
• Loading areas—fit in grooves.
• Deciduous molars—anchor teeth.
• Edentulous areas.
• Noses.
• Labial bow—prevents post displact of appli
Dentofacial orthopaedics with functional appliances-Graber,Rakosi,Petrovic
21

22. TRIMMING THE BIONATOR
Balters terminology refers to
• stimulation of eruption - as unloading or
promotion of growth.
• prevention of eruption - as loading or
inhibition of growth.
The difficulty in managing bionator is the alternate
loading and unloading of certain areas.
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23. Standard twin
block
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24. 24

25. OBJECTIVES
 Harmonious development of the dentofacial
structures
 Eliminate unfavorable myofunctional and
occlusal factors
 Establish new functional behavior pattern
 Unlock the malocclusion
 Stimulate growth by applying favorable forces
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26.  In 1977,
Dr. William J. Clarks
 Developed Twin Block
 A significant transition
from one piece
appliance that restricts
the normal function to a
twin appliance that
promotes normal
function.
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27. Goals
 To produce a technique that could
maximise the growth response to
functional mandibular protrusion by
using an appliance that is simple,
comfortable and aesthetically
acceptable to the patient.

28. 28

29.  Occlusal inclined plane
 Fundamental functional mechanism of natural dentition.
 Cuspal inclined plane determines the relationship of teeth
as they erupt into occlusion.
If mandible occludes in distal relationship to maxilla.
Occlusal forces have distal component forces .
Unfavorable for normal forward mandibular development
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30.  PROPRIOCEPTIVE STIMULUS OF GROWTH
 NEW FUNCTIONAL BEHAVIOURAL PATTERN
ESTABLISHED
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31. POSITION OF OCCLUSAL
INCLINED PLANE
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32. MAXILLARY BITE BLOCK
Inclined plane on upper block- Angled from ---Mesial
surface of upper 2nd premolar (or deciduous second molar)
to mesial surface of lower 1st molar.
Mesial to lower 1st molar so not to obstruct
eruption of mandibular molar in deep bite.
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33.  Upper arch wider then lower so cover only palatal
cusp of upper posterior teeth rather then full
occlusal surface covered with acrylic.
Advantage
 Make clasp more flexible
 Allows access to interdental wire for clasp
adjustment. 33

34. MANDIBULAR BITE
BLOCK
 Inclined plane on lower block- angled from distal
surface of lower 2nd premolar or deciduous second
molar 700 to occlusal plane.
 Thinner buccolingually in lower canine region.
Reducing bulk improve speech by allowing tongue
freedom of movement in phonetic.
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35. Buccolingually the lower block covers the occlusal surfaces
of the lower premolars or deciduous molars to occlude with
the inclined plane on the upper Twin Block.
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36. ADVANTAGE OF
TWIN BLOCK APPLIANCE
1. Comfort
2. Aesthetics
3. Function
4. Patient compliance
No visible anterior wire
Mandible free to move normally in
anterior and lateral excursion, without
restricted by bulky appliance
Fixed to teeth temporarily or
permanently to guarantee patient
compliance
Pt can eat comfortable with
appliance in mouth
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37. 5. Facial appearance
6. Speech
7. Arch development
8. Facial asymmetry
Do not restrict movement of Tongue
and Lips
Improve due to absence of buccal
shield, lip pad as was in frankels
appliance
Independent control of upper and
lower width , easily modified for
transverse and sagittal arch
development
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38. 9. Efficiency
10. Integration with fixed appliances
11. Treatment of Temporomandibular dysfunction
More rapid correction then 1 piece appliance because worn full
time a day
Twin block (for skeletal correction) do not have anterior wire so
bracket (for detailing occlusion) placed on anterior teeth, during
support phase easy transition be made to fixed appliance
Used as splint in treatment where due to displacement of condyle
distal to articular disc of patient .
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39. IDEAL CASE
 Class II div 1 with a good arch form.
 Lower arch uncrowded
 Upper arch aligned
 Increased Overjet and a deep bite.
 Full unit distal occlusion.
 on advancement the distal occlusion should get
corrected.
 On clinical examination profile should be
noticeably improved when patient advances the
mandible (VTO positive)
 Patient should be growing actively preferably
should be in pubertal growth spurt. 39

40. COMPONENTS
OF TWIN BLOCK
 Midline screw
 Clasps
 Ball end clasp
Labial bow
 Springs
To expand arch
To link teeth as anchor
units
To move individual teeth to
improve arch form
ARCH
WIRE
COMPONENT
ACRYLIC
COMPONENT
• Base plate
• Occlusal bite blocks with
inclined plane
Prevent proclination of
anteriors
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41. i) Labial
bow
 Overcorrect incisor inclination.
 Retracting upper incisor prematurily limit scope of functional
correction by mandibular advancement.
Labial bow not always required unless necessary to upright
severely proclined incisors, e.g angle’s class II div 1
 Not activated until full functional correction and class 1
buccal segment relation achieved.
Twin Block Functional Therapy Application in Dentofacial Orthopaedics 2nd edition William J.Clark
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42.  In Twin Block treatment a good lip seal is achieved
naturally without additional lip exercises.
 As the appliance is worn for eating and drinking, making
it necessary to form a good anterior seal
 The lips ======= labial bow
 Lip pressure is effective in uprighting upper incisors,
making a labial bow superfluous.
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43. MODIFICATION
Addition of incisal capping over lower incisor
Prevent proclination of lower incisors
Growth studies show lower incisors procline by 5 degree
They upright during support phase.
Decalcification of tips of lower incisors where oral hygiene
poor.
DISADVANTAGE OF INCISAL CAPPING
Twin Block Functional Therapy Application in Dentofacial Orthopaedics 2nd edition William J.Clark
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44. ii) DELTA CLASP:
Designed by William J Clark in (1985),
LOCATION OF DELTA CLASP-
On upper 1st molar and lower 1st premolar for retention and stability
Also on deciduous molars.
Twin Block Functional Therapy Application in Dentofacial Orthopaedics 2nd edition William J.Clark
44

45. iii) BALL END CLASP
FUNCTION--Improve retention from adjacent teeth.
--Provide resistance to anterioposterior tipping.
LOCATION-- mesial to lower canine and in upper premolar or
deciduous molar region to gain interdental retention
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46. ACRYLIC COMPONENT
i) Occlusal Inclined Plane
FUNCTION
 Acts as guiding mechanism causing
mandible to displace downward and
forward.
 Give greater freedom of movement in
anterior and lateral excursion and cause
less interference with normal function.
 Determine relationship of teeth as they
erupt in occlusion.
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47. ii) BASE
PLATE

Heat cure Cold cure
 Speed
 Convenience
 Sacrifice in strength,
accuracy.
 Strength
 Accuracy
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Twin Block Functional Therapy Application in Dentofacial Orthopaedics 2nd edition William J.Clark
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48. INSTRUCTION ABOUT TWIN BLOCK
 Wear the appliance full time.
 Take the appliance out for cleaning your teeth, contact sports
and swimming.
 Patients should wear it at meal times. This requires a little
practice but is worth the effort.
 At first may be a little uncomfortable but gradual adjustment
will come .
 Try to keep the blocks in contact at all times.
Twin Block Functional Therapy Application in Dentofacial Orthopaedics 2nd edition William
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49.  Learn to speak with your teeth together.
 Keep the appliance very clean by brushing.
 Appliance is expensive to make and so patients must
take care of the appliance.
 Store the appliance in a plastic box when not in use and
DO NOT wrap in tissue paper .
 Fluoride mouth rinse
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50. The Twin Block appliance reduces overjet in Class II, Division
1 malocclusion by means of favorable skeletal changes in
bony bases and dentoalveolar compensations.
Mandibular growth changes were significant amongst all
cervical stages. However, they are more pronounced when
appliance is placed during the CS-3 stage, as compared to
CS-2 and CS-4 stages.
Any attempt to change the growth is best achieved at the
peak of pubertal growth; therefore, it is better to wait for CS-3
to achieve maximum skeletal effects as well as to reduce
overall treatment duration.
Dentoalveolar changes were also minimal during treatment in
CS-3 stage, as compared to CS-2 and CS-4 stages.
CONCLUSION
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