2. CORRECTION OF CLASS 2 SKELETAL PROBLEMS
Orthopaedic restraint of maxillar y growth(headgear).
Enhancement of mandibular growth in aldolescent (Functional appliance)
Orthognathic surgery in adults.
3. DEFINITION:
Headgear is an extraoral orthopaedic appliance use to restrain the
downward and forward growth of maxilla.
4. COMPONENTS OF HEADGEAR
Force delivering unitFacebow/J hook (they Transmit forces)
Force Generating Unit Springs/Elastics
Anchor Unit Headcap/ Neck Strap (they direct forces above or below occlusal
plane)
6. HIGH PULL/OCCIPITAL HEADGEAR
Headcap is attached to back of head in occipital region or junction or parietal &
occipital.
Exerts Superior and Distal force to maxilla and maxillary dentition
Force on maxillary molars Distal and Intrusive.
Line of force Pass through C.O.R Bodily movement
Pass above C.O.R Distal Root tip
Pass below C.O.ODistal Crown tip
Outer Bow is Short and Bent Upward (superior Vector Force)
INDICATIONS: High mandibular angle cases
Excessive vertical Maxillary Growth
Open Bite.
7. LOW PULL/CERVICAL HEADGEAR
Derives its anchorage from Nape of the Neck.
Exerts Inferior and Distal force to Maxilla.
Force on Maxillary Molars Distal and Extrusive.
Line of Force Pass through C.O.R Bodily movement
Pass Above C.O.R Distal Root tip
Pass below C.O.R Distal Crown tip
Outerbow is Long and Bent Downward (Inferior Force Vector)
INDICATIONS: Low Madibular plane angle.
Decrease Vertical Growth
Deep bite.
8. COMBIPULL/STRAIGHT HEADGEAR
It has both occipital and cervical strap.
Exerts Distal and Slight upward Force on Maxilla and Maxillary teeth.
INDICATIONS: In Normal/average Manibular plane angle.
Vertical Maxillary excess.
9. SELECTION OF HEADGEAR
It Depends upon:
Selection of required movement bodily or tipping movement
Headgear anchorage location High or low angle cases.
Headgear dentition attachment points Tubes of maxillary molars(facebow)
Maxillary splint(on Premolar teeth)
Functional appliance.
10. MAGNITUDE OF FORCE AND DURATION
1)MAGNITUDE:
a)SKELETAL: 350-450 gms/side
b)DENTAL: 100-200 gms/side (*by anchorage)
2)TYPE OF FORCE: Intermittent forces
3)DURATION OF WEAR: 12-16 hours/day
night time wear8pm-1am
(GH release high)
11. LIMITATIONS OF HEADGEAR USE
Pateint compliance
Slower tooth movement with intermittent force
Delayed eruption of max second molars or impactions.
12. ENDOGENOUS FUNCTIONAL APPLIANCE EFFECT:
Mandibular growth in AP direction is necessary part of response to headgear
use.There is some evidence of increased mandibular growth during treatment
of headgear. Headgear doeas appear both maxillary and mandibular effect.
13. JUDGEMENT OF PATIENT(APPLIANCE WEARING OR NOT)
Tell patient to wear appliance in front of you
Slight mobility of first premanent molar
Marks of appliance wear.
Calculus deposits around appliance.
14. USES OF HEADGEAR
ORTHOPAEDIC: 350-450gms/side ; 10-12 hours wear ; 12-18 months
ANCHORAGE: Reinforcement of anchorage during fixed appliance
250-350gms/side ; 10-2 hours/day.
DISTALIZATION OF MAX 1ST MOLAR: To correct molar relationship 300gms/side.
if unilateral class 2asymmetric headgear
SPACE MAINTENANCE & REGAINING: space maintenanceasymmetric headgear
space regainingdur to premature loss of
decidous teeth.
INTRUSION OF MOLARS AND INCISORS: By using High pull headgear and
Maxillary splint.
EXPANSION OR CONTRACTION OF ARCH: By adjusting inner bow
UPRIGHTING OF MOLARS: mesially tipped molars can be upright
15. After removal of headgear downward and forward rotation
of maxilla was observed. Relapse was limited to teeth and
not to nasomaxillary complex, suggesting that the skeletal
effect is permanent. Class 2 correction was maintained
through a more pronounced growth in mandible and not
necessarily from molar correction.
Facebow headgear:1)retraction of teeth2)Restriction of mesial drift associated with growth3)Restriction of meial drift associated with early loss of decidous teeth4)reduction of slippage of posterior teeth in extraction5)increase of vertical anchorage5)restraints upperjaw6)Reduction of teeth eruption7)protraction of teeth
Class 2 division 2 cases
Timing of treatment:prealdsolesecnt: cvm 2 or 3 if maxillar cvm 3 if mandibleearly aldolescent: before transition complete growth leeway space: decidous molars are larger mesiodistally than permanent molars 0.5-1mm space is time poe dete headgear
Rale effect: opposite to endogenous functional appliance effect.