Dr Abdul Jabbar

Facemask and Chin cup

Growth modification appliances for skeletal Class III.

What are facemasks and chin cups?

CLASS III MALOCCLUSION

The relative mesiodistal relation ship of arches are

abnormal with all the lowerteeth occluding mesial to normal ,producing markeddisharmony in the incisor

region and in the facial lines.

Abnormal relationship in which the mesiobuccal cusp of max. first permanent molar occludes distal to the buccal groove of mandibular first molar.

CLASS III MOLAR RELATION SHIP

DENTALFUNCTIONAL

SKELETAL

TYPES OF CLASS III MALOCCLUSION

Short Maxilla

Prognathic Mandible

Composite

Early loss of lower e`s

Dental Class III

FEATURES No apparent saggital discrepancy

ANB angle is with in normal limits

Lingual tipping of max. incisors & labial tipping of mand. incisors

DENTOALVEOLAR MAL-RELATIONSHIP

ETIOLOGICAL FACTORS FUNCTIONAL (PSEUDO)

CLASS III MALOCCLUSION

Ectopic eruption of maxillary central incisors

Premature Contact

Premature loss of C`s

Dental factors

• Anomalies in tongue position • Neuromuscular features

• Naso-respiratory or airway problems

Functional factors

Minor transverse maxillary discrepancy

Skeletal Factor

Mandible appear morphologically normal

Class I or mild Classlll sk. Relationship

Ant. cross bite and negative over jet is present due to a ant Displacement of mandible

Mandible can be pushed back to edge-edge relationship

FEATURES OF PSEUDO CLASS III

1. GROWTH MODIFICATION Pre Adolescents (late childhood ,

juvenile) Adolescents (v. minimal effects)

2. CAMOFLOUGE (MILD) Adolescents Adults

3. Orthognathic SURGERY (moderate –severe)

Post adolescents Adults

SK CLASS III

CAUSES DEFICIENT MAXILLA PROGNATHIC MANDIBLE COMPOSITE

GROWTH MODIFICATION

Orthopedic face mask correct classIII malocclusion in:

Late decidious or early permenant dentition

Changes produced in all three plane of spaces

FACE MASK THERAPY

Correction of CO_CR discrepancy Maxillary sk. Protraction Forward movement of max.dentition Lingual tipping of lower incisors Redirection of mand. Growth in more

vertical direction

TREATMENT EFFECTS PRODUCED BY FACE MASK THERAPY

TREATMENT IN GROWING PATIENTS(pre- adolescents , adolescents)

• Skeletal Class III with Short Maxilla

FR 3 (22-23 hrs)

Effects

• Forward mov.of maxilla• Proclination of upper incisors• Backward rotation or repositioning of mand. • Increase in lower ant. Facial height • lingual tipping of lower incisors

TREATMENT IN GROWING PATIENTS(pre adolescents , adolescents)

• Composite Skeletal Class III -ive Family History

Face Mask or Reverse Headgear

Effects

• Maxillary sk. Protraction• Forward movement of max.dentition• Lingual tipping of lower incisors • Redirection of mand. Growth in more vertical direction

Pre-requisite Maxillary Expansion

Treatment effects of facemask

Incease in overjet (4.4 mm)Mesial mov. &flaring of upper incisors & up righting of lower incisors

& correction of molar position towards class I molar correction(3.1 mm)mesial mov. Of maxilla

Skeletal effects ANB angle (2.4-2.8)& Witts

appraisal(witts value 2.6mm)

Treatment effects

DEFICIENT MAXILLA/COMPOSITE III

Expansion + face mask 8 yrs ideal age for maxillary protraction. more the age of the patient ,less will be the skeletal effects. early ages treatment ensures better skeletal effects.

Treatment & Management

in Pre-adolescence

Criterea for facemask:1. Short face Normal face2. Lower incisors either normally

inclined or proclined.3. Upper incisors must be either

retroclined or normally inclined.4. Growing 8yrs age ideal for facemask

Facial mask Bonded max. expansion splint Heavy elastics

Components of orthopedic facial mask therapy

Orthopedic face correct classIII malocclusion in

Late decidious or early permenant dentition

Changes produced in all three plane of spaces

FACE MASK THERAPY

Facemask therapy often follows maxillary expansion since the latter disrupts the circummaxillary sutural system and facilitates the orthopedic effects of the facemask

children treated at an early age, showed a

significant forward displacement of the maxillary complex and a significant upward and forward direction of condylar growth, leading to smaller increments in total mandibular length

Facial mask

1. Delaire facemask

2. Petit facemask

Types of facemasks

made of two pads that contact the soft tissue in the forehead and chin regions..

The pads are connected by a rod

In the center of the midline framework is adjustable crossbow to which elastics are connected bilaterally

Facial mask

The second component of this orthopedic treatment is the maxillary splint. an acrylic and wire maxillary expansion appliance that is bonded to the posterior dentition.

In mixed dentition cases, the splint usually covers the first and second deciduous molars.

The upper canines may also be included in patients who present with complete deciduous dentitions.

2 .Max.expansion splint

maxillary splint is made of a framework of .045“(1.2mm) round stainless steel wire, to which an expansion screw is attached.

If second molars are present, an occlusal rest is extended to the second molars to prevent overeruption of these teeth during treatment (Two hooks, to which elastics are attached, are soldered to the wire framework.

These hooks usually lie adjacent to the canines or first deciduoud molars.

Max.expansion splint

, Rapid palatal expansion can produce a slight forward movement of Point A and a slightdownward and forward movement of the maxilla.

In the context of facial mask therapy, the effect of such expansion is to disrupt the maxillary sutural system, thus possibly enhancing the effect of the orthopedic facial mask by making sutural adjustments occur more readily.

Max.expansion splint

Another advantage of maxillary expansion is the correction of the posterior crossbite that often accompanies a Class III malocclusion because of deficient transverse maxillary growth and the abnormal anteroposterior relationship of maxilla to mandible.

In addition, a palatal expansion appliance splints the maxillary dentition during protraction and helps transmit force from the teeth to the maxilla, thus limiting unwanted tooth movement.

The patient is usually instructed to turn the midline jackscrew of the appliance once daily, generally before bedtime.

In the majority of Class III individuals in whom use of an orthopedic facial mask is indicated, some maxillary expansion is beneficial. In such a case, the maxillary splint is expanded until the desired transverse change is achieved.

Activation of splint

In instances in which no transverse change is necessary, the maxillary splint is activated once a day for eight days to produce a disruption in the sutural system that facilitates the action of the facial mask

Activation of splint

The facial mask is secured to the face by stretching elastics from the hooks on the maxillary splint to the crossbow of the facial mask

Heavy forces are generated, usually through the use of 5/16", 14oz elastics bilaterally.

Lighter forces may be used during the break-in period, but forces should be increased as the patient adjusts to the appliance.

Heavy elastics

Optimally, the patient is instructed to wear the facial mask on a full-time basis except during meals.

Young patients (5 to 9 years old) can usually follow this regimen, particularly if the patient is told that the full-time wear will last only three to five months.

In older patients, full-time wear may not be possible, in which case the appliance should be worn at all times except when the patient is in school or participating in contact sports

INSTRUCTIONS

The facial mask is usually worn until a positive overjet of 2-4mm is achieved interincisally. At this time, part-time or nighttime wear is recommended for an additional three to-six-month retention

FR-3 Frankel appliance1 can be worn as an active retainer.

FACIAL MASK

Extra oral force application can be accomplished in 2 ways:

1. EO force through condyles2. EO force below the condyles.

Skeletal classIII with large mandible

Chin cup Types of chin cup

What appliance?

Pre adolescents, mild, no family history, low angle

Chin Cup Adolescents ,mild Class III ,low angle. Chin Cup or surgical preparation.Adults Camoflouge of surgery

SKELATAL CLASS III WITH LARGE MANDIBLE

Mandibular growth mechanisms1. functional matrix theory2. displacements primary and s secondary.3. Growth sites and growth centers.4. Drift , relocation, sub periosteal

deposition and resorption, modelling,remodelling.

growth philosophy

TREATMENT IN GROWING PATIENTS

Skeletal Class III with Prognathic Mandible-ive Family History

1. Reverse Twin Block ( appliances without lip pads)

2. Chin Cup 1. Occipital Pull

2. Vertical Pull

150-300 gm per side (INITIALLY)450-700 gm (if force is directed through condyle & slightly less if below the condyle)14 hrs per dayAfter correction of cross bite wear only at night as retention appliance

CHIN CUP TYPE HEAD GEAR

Chin cup types

1.OCCIPITAL- PULL CHIN CUP

2.VERTICAL PULLCHIN CUP

Mild to moderate mand. Prognathism Short lower ant. Facial hgt. Normally positioned or slightly

proclined lower incisors(some backward tipping of lower incisors)

OCCIPITAL- PULL CHIN CUP

Chin cup

If below the condyle-----downward

&backward rotation of mandibleIf no opening of mand. Plane is

required forceshould be directed through condyle to help restrict mand. Growth.

Direction of pull of chin cup

150-300 gms per side (INITIALLY)OVER NEXT 2 MON. 450-700 grams(if force is directed

through condyle & slightly less if below the condyle )(16-24 ounce)

14 hrs per day After correction of cross bite wear

only at night as retention appliance.

FORCE

INDICATIONS Inc. ant. vertical dimention Steep mand. Plane angle

VERTICAL PULLCHIN CUP

If no Inc. in lower ant. Facial ht. is required

EFFECTS PRODUCED

Dec. in Mandibular Plane angle & Gonial angle

Increase in posterior face height.

2.VERTICAL PULLCHIN CUP

A-Unitek B-Summit

Could be I. pre formedII. custom made metallic plastic Talcum powder Soft chin cups Vs hard chin cups

Clinical Management

Mandibular growth is redirected in downward and backward direction.

Increased LAFH LI are retroclined. Decreased chin prominence.

Effects of chin cup therapy

Effects of chin cup therapy