1. SEMINAR ORTHODONTICS: TWIN BLOCK & FRANKEL APPLIANCE
GROUP 5:
MASYITAH MUSTAFFA
SAKINAH MOHD SALEH
NURMARZURA ABDUL LATIF
SYAFIQAH NADHIRAH ISKANDAR

2. Introduction Functional appliance:
“removable or fixed orthodontic appliances that aim to utilise, eliminate or guide forces arising from muscle function, tooth eruption and growth in order to alter skeletal an dental relationships”.
Types:
Tissue-borne Frankel appliance
Tooth-borne (active) Twin block
Tooth-borne (passive) Andresen appliance
Myotonic Harvold activator

3. TWIN BLOCK removable functional appliance.
made up of two components, an upper and lower plate, which works together to posture the lower jaw forward.
frees up the “locked-in” lower jaw and encourages it to grow to its fullest potential.
the upper (and sometimes lower) plate may also have an expansion screw to widen the arch.
treatment with a Twin Block appliance typically takes 12 to 18 months.

6. MODE OF ACTION
works on the philosophy of occlusal inclined planes and use of masticatory force throughout the day.
If the mandibular inclined planes are in a distal relation to that of maxilla then the force acting on the mandibular teeth will have a distal force vector leading to a Class II growth tendency.

8. The aim of the inclined planes of the bite blocks in twin block is to modify these inclined planes and cause more favorable growth pattern.
Hence the unfavorable cuspal contacts of the distal occlusion are replaced by favorable proprioceptive contacts on the inclined planes to correct the malocclusion and free the mandible from its locked distal position.

9. Adjustment of the occlusal plane: deep overbite case
the upper block should be slightly trimmed occluso-distally to leave the lower molars 1 mm clear of the occlusion to allow for eruption
This is usually done at the first visit, with subsequent reductions performed, as needed, until the proper vertical relationship is established.
reduced overbite (or open bites) case
very important that NO trimming is done on the blocks.
all posterior teeth must remain in contact with the blocks to PREVENT eruption of the posterior teeth.

11. Appointment Scheduling:
First Appointment: Delivery of the appliance and patient instruction. Adjustment of the occlusal planes. One Week Later: Adjust the bite blocks if the lower molars have erupted into contact. For arch development, have the patient begin expansion screw activation at one turn per week. One months Interval:check adjustment. Watch for proper vertical, lateral and AP development.

12. Class II div I Malocclusion
INDICATIONS
BASIC USE
Class II div I Malocclusion
70% malocclusion Majority have  Constricted maxilla Retrognathic mandible N/short lower face height Large OJ Deep OB

14. INDICATIONS Class II div I Class II div 2 Class I OB
Class I closed bite
Class III
Lateral arch constriction
Anterior/posterior arch length discrepancies
Can also be used in TMJ therapy

15. INDICATIONS Permanent dentition and active grower
Uncrowded dentition with well developed arches
10mm or less overjet with normal to deep overbite
Improved facial esthetics once the mandible is brought forward to class I
Normal growth direction

16. INDICATIONS
Note: if patient is Class II div 2 with limited overjet or Class II div 1 with crowded and irregular incisors, you must align the upper incisors with a fixed or removable appliance before starting a twin bloc. It is recommended to hold the incisors in place for several months before delivering the appliance

17. CONTRAINDICATIONS
Tx aim is to relate mandible to maxilla in 3D Transverse, AP and vertically. Requires Maxilla to be in correct position first

18. CONTRAINDICATIONS Maxilla must be in proper width
Ensure NO skeletal or facial asymmetry
Maxilla incisors must be torqued correctly
Maxillary incisors should not be too vertical or lingually inclined (as in Class II div 2)

19. Standard Twin Blocks – Class II Div I (with good arch arch form)
Components
C-TYPE 1
Standard Twin Blocks – Class II Div I (with good arch arch form)
Adams or Delta Clasps, and Anterior Ball Clasps for good retention
Twin Blocks at a 70º angle, to advance mandible
Upper Midline Screw: so upper arch can accomodate
lower arch in advanced position

20. Standard Twin Blocks – Class II Div I (with crowded lower arch)
Components
C-TYPE 2
Standard Twin Blocks – Class II Div I (with crowded lower arch)
• Adams or Delta Clasps, and Anterior Ball clasps for
good retention
•Twin Blocks, at a 70º angle, to advance mandible
• Upper and lower Midline Screws

21. Stage II – Support Phase
Components
C-TYPE 3
Stage II – Support Phase
Anterior Inclined Plane used to maintain the corrected
AP and incisor relationship until buccal segments settle
into full occlustion.
*Molars must be in contact to begin Stage II

22. Class II Div II Twin Block
Components
C-TYPE 4
Class II Div II Twin Block
• Adams or Delta Clasps
•Twin Blocks, at a 70º angle, to advance mandible
• Upper and lower Midline Screws
• Lingual Springs to move anterior forward
To Open Bite: Reduce upper bite block as ilustrated above

23. Class II Div II Twin Block “Saggital”
Components
C-TYPE 5
Class II Div II Twin Block “Saggital”
• Adams or Delta Clasps, and Ball clasps
• Standard 70º Twin Blocks
• Adjust screws ¼ turn per week to advance anteriors
To Open Bite: Reduce upper bite block as ilustrated above

24. Twin Block to close the Bite
Components
C-TYPE 6
Twin Block to close the Bite
• Adams or Delta Clasps
• Standard 70º Twin Blocks
• Tongue guard to prevent tongue thrust and act as Inclined plane to support the corrected incisor relationship
• Lower Acryclic extended to 6’s with indicated clasps
• Acrylic relieved lingual to anteriors to encourage reduction of open bite

25. FRANKEL APPLIANCE
‘ It is a tissue-borne type removable functional appliance developed by Rolf Frankel that aims to remove muscle forces in labial and buccal areas that restricts the skeletal growth’

27. Also known as functional regulator (FR).
Use during mixed and early permanent dentition stages
Widely used in Class II malocclusion
It produces changes in anteroposterior, transverse, and vertical jaw relationships
Worn full-time basis for months.
Then, part-time basis until the fixed appliance are placed to align permanent teeth.

28. Indications Frankel’s regulator 1 FR-I a FR-I b FR-I c
To treat class I and class II division malocclusion
to treat Angle’s class I malocclusion with deep bite
To treat Angle’s class II division I malocclusion, OJ not exceed 5mm
to treat Angle’s class II division I malocclusion, OJ more than 7 mm
FR-II
to treat Angle’s class II malocclusion division I and class II malocclusion
FR-III
to treat Angle’s class III malocclusion
FR-IV
To treat bimaxillary protrusion and open bite
FR-V
Used with headgear

29. Components Frankel’ regulator Acrylic components Wire components FR I
2 vestibular shields
2 lip pads
Palatal bow
Labial bow
Labial support wire
Lingual bow
Canine loops

30. Components Frankel’ regulator Acrylic components Wire components FR II
Buccal shields
Lip pads
Lower lingual pad
Palatal bow
Labial bow
Canine extensions
Upper lingual wire
Lingual crossover wire
Support wire for lip pads
Lower lingual springs

31. Frankel’ regulator
Acrylic components
Wire components
FR III
2 upper lip pads
Buccal shields
Labial support wire
Labial bow
Protrusion bow
Palatal bow

32. Frankel’ regulator
Acrylic components
Wire components
FR IV
2 lower labial pads
2 vestibular shields
Protrusion bow
Occlusal rests
Palatal wire

33. Frankel’ regulator
Acrylic components
Wire components
FR V
Posterior acrylic bite blocks

34. Mode of action
Mandibular protraction mandibular repositioning is provided by inferior border of vestibular shield, lower labial pad and lingual shield.
Muscle function adaptation: pads and shields massage the blood vessels increase circulation.
Lateral expansion Max;4-6mm. Mand;2-4mm. Due to vestibular shield inhibits cheek muscle from acting against occlusion. Thus allow the tongue to determine the lateral positioning of the teeth.

35. Increase in saggital and transverse intraoral space.
Increase in vertical space where appliance is kept free from posterior teeth.
Shields loosen up tight muscle and improve muscle tone

36. References
Textbook Orthodontics Principles and Practice, Daljit S. Gill & Farhad B.Naini, 2011
Twin_Block_Ortho_4_Eng-web7-2.pdf
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37. Thank you