Activator and its modifications /certified fixed orthodontic courses /certified fixed orthodontic courses by Indian dental academy

ACTIVATOR AND ITS MODIFICATIONS

INDIAN DENTAL ACADEMY

Leader in continuing dental education www.indiandentalacademy.com

www.indiandentalacademy.com

ACTIVATOR AND ITS MODIFICATIONS…

Catch them Young

Watch them Grow


History…

Kingsley(1879) – “ jumping the bite ”

Robin 1902- Monobloc.

Viggow Andresen (1908)

Andresen and Haupl (1955)

- Activator.


Mechanism of Action…

MECHANISM OF THE STRETCH (OR) MYOTATIC RELEX:

How does it work? Monosynaptic? Postural rest position? Isometric contractions?www.indiandentalacademy.com

My View…


Harvold and Woodside ,Herren ,Selmer-Olsen

viscoelastic properties of soft tissue

Rationale? www.indiandentalacademy.com

Bite registered for 3mm to 4 mm distal to the most protruded

position is to avoid the possibility of initiating Golgi tendon

organ activity and thus eliminate any undesirable myotatic reflex

Witts supported a combination of isometric muscle contractions

and viscoelastic properties being responsible for the forces

delivered by the activator and used intermediate construction

bite height.

Eschler attributed the muscle contraction to proprioceptive

stretch reflexes and observed the occurrence of both isometric

and isotonic contraction with use of the activator. www.indiandentalacademy.com

Types of forces in activator therapy

Forces employed in activator therapy are categorized as,

The growth potential, including the eruption and migration of

teeth, produces natural forces; these can be guided, promoted

and inhibited by the activator.

Muscle contractions and stretching of the soft tissues initiate

forces when the mandible is relocated from its postural rest

positions by the appliance. Whereas forces may be functional in

origin, the activation is artificial.


Artificially functioning forces can be effective in three planes

Sagittal plane:

Mandible is propelled down and forward.

muscle force is delivered to the condyle and a strain is produced

Slight reciprocal force can be transmitted to the maxilla during this maneuver.

Vertical Plane:

Teeth and alveolar processes are either loaded with or relieved of normal forces.

if construction bite is high, a great strain is produced

if transmitted to the maxilla, these forces can inhibit growth increment and direction and influence the inclination of the maxillary base. www.indiandentalacademy.com

Transverse plane:

Forces can be created with midline corrections.

Various active elements like springs, screws can be built in to the

activator to produce an active biomechanical type of force

application.

The mode of force application, magnitude and direction depend

on the three dimensional dislocation of the mandible, which is

determined by the construction bite.


Activator

The original appliance

consists of a combined upper

and a lower plate at the

occlusal plane only one-wire

elements was used i.e. A

labial arch for upper anterior

teeth.


Construction Bite

♫ Edge-to-edge incisal relationship to stimulate the mandibular growth. The construction bite for the activators was taken with the lower jaw in class I or over corrected class I molar relationships

♫ Vertical opening not beyond rest position of the mandible


EFFECT OF ACTIVATOR TREATMENT

Skeletal ChangesClass II Div I)

The Skeletal effect of the activator depends on growth potential.

Two divergent growth vectors propel the jaw bases in an

anterior direction.

The sphenoccipital synchordrosis moves the cranial base and

nasomaxillary complex up and forward

The condyle translates the mandible in a downward and forward

direction.



In contrast to primary cartilages (epiphyses, sphenoccipital

synchondroses) a condylar growth is regulated to a high degree

by local exogenous factors.

Petrovic - forward posturing of the condyle activates the

superior head of LPM and condylar growth.

The activator can, to a limited degree control the upper growth

vector supplied by the sphenoccipital synchondrosis, which

moves the maxillary base forward.

Total anterior facial height increases with lower facial height

increased by more than twice as much.


ROLE OF RETRODISCAL PAD:

The Retrodiscal pad controls mandibular growth in two ways.

The vascular component controls the condylar cartilage growth

rate and endochondral ossification rate.

An increase in interactive activity of the retrodiscal pad

produces an increase in condylar cartilage growth and

endochondral ossification.


An increase in interactive activity of the retrodiscal pad -accentuation of the ramus posterior concavity and a local increase in bone apposition and the number of negative charges at the ramus posterior concave surface.

Accentuation of the ramus anterior convexity and local increase in bone resorption and number of positive charges at the ramus posterior convex surface.www.indiandentalacademy.com

Dento Alveolar Effect

♫ The improvement in sagittal occlusal relationship was due

about equally to skeletal and dental charges.

♫ Overjet correction- mandibular growth exceeding maxillary

growth and distal movement of the maxillary incisors.

♫ Class II molar correction -mandibular growth exceeding

maxillary growth and mesial movement of the mandibular

molars.


♫ Inhibits maxillary growth, move the maxillary incisors and

molars distally and move the mandibular molars and incisors

mesially.

♫ Lingual tipping of maxillary incisors and labial proclination of

the mandibular incisors related to significant reductions in

overjet. Thus passive upper labial wire of activator intended to

avoid upper incisor tipping and acrylic cap on the incisal third of

the lower incisors can prevent proclination


Soft tissue changes Retraction of upper anterior teeth, followed by a similar

dropping back of the upper lip, improve a protrusive profile.

Stoner’s and associates found that,

Soft tissue improvements were produced by four principal changes.

The gross movement of incisors

A reduction in the curl of the lower lip.

Vertical opening of the chin.

Forward positioning of the chin.

Reduction of overjet has the effect of uncurling both lips, which enables the lips to hold together without undue effort.


Class II Div 2 malocclusions

The upper central incisors are tipped labially by springs at the

incisal margin.

The labial bow exerts lingual pressure at the labial gingival

margins to achieve lingual root movement.(Herren activator

preferred)

Open bite and Cross bite?


Construction biteBite is taken by retruding

the jaw. The extent of vertical opening depends on the retrusion possible.

REVERSE ACTIVATOR


In Functional Protrusion Class III Malocclusion

The mandibular incisor hit prematurely in an end-to-end contact, and the mandible then slides anteriorly to complete the full occlusal relationship.

The vertical dimension of construction bite is opened far enough to clear the incisal guidance, which eliminates the protrusive relationship with mandible in centric relation.

The prognosis for pseudo class III malocclusion is good, especially if therapy is started in early mixed dentition. In early mixed dentition period, skeletal manifestation are not usually severe, since the malocclusion develops progressively.


Appliance

Mandibular labial bow is used to guide the mandible distally, as the teeth occlude.

The maxillary labial bow If needed kept away from labial surfaces to relieve any lip pressure.


The acrylic was relieved on lingual surface of mandibular incisors and maxillary incisors supported with close contact.

Maxillary incisors are tipped labially with small screws, wooden pegs (or) lingual springs (or) by application of gutta percha lingual to incisors.

Concurrently force was eliminated in the upper arch with maxillary lip pads to allow the fullest extent of growth potential


Changes

Articular angle increased because of posterior positioning

mandible

Mandibular plane angle slightly opened.

SNA increased

ANB increased

Maxillary incisor tipped labially

Mandibular incisors tipped lingually.


In a skeletal class III malocclusion with a normal path of closure

from postural rest to habitual occlusion, the treatment with

functional appliance is not always possible.

The true mandibular prognathism is undoubtedly one of the

most difficult conditions to treat orthodontically.


HARVOLD – WOODSIDE ACTIVAOR

Harvold (1974) and Wood side (1973)

Wood side opens the mandible with the construction bite as much as to 10 – 15 mm beyond postural rest vertical dimension.

The forces generated by this extreme bite registration (10-15 mm) represent combination of forces generated by swallowing, biting, activation of the myotatic reflex in the stretched muscles of mastication and the power delivered through the viscoelastic properties of stretched muscles, tendon tissue, Skin and musculature.

This appliance works using potential energy.


Class II Div I with increased

LAFH (environmental factors) Actual adaptation of the maxilla to

the lower dental arch. Partially achieved by retroclination

of the maxillary base. Differential eruption of teeth good vertical control of both

dental arches and only minor

forward tipping of the lower

incisors.


Harvold has also emphasized the concept of the “Functional occlusal place” and the role played by its manipulation in the successful correction of class II malocclusions. This plane represents the functional table of occlusion in the first permanent molar, second molar and first premolar areas.


The level and inclination of the functional occlusal plane is the result of the neuromuscular, growth and developmental forces acting on the dentition.

The correct manipulation of the functional occlusal plane involves the inhibition of maxillary buccal segment eruption, which normally follows a downward and forward curvilinear eruption path.

At the same time mandibular buccal segment are permitted to erupt vertically in harmony with the vertical growth of the lower face.

Because the mandibular molar erupt roughly at right angles to the functional plane, change from class II malocclusion to class I occlusion is facilitated.


Appliance with dislodging springs


Class III malocclusion


HERREN ACTIVATOR The principle-complete

opposition to the kinetic concept of Andersen – Haupl appliance.

By overcompensating the ventral position of the mandible in the construction wax bite.

By seating the appliance firmly against the maxillary dental arch by means of arrowhead clasps similar to those used in active plates.www.indiandentalacademy.com

Mode of action

Graber coined the term “myotonic appliance”.

The mandible is prevented from assuming the natural rest-

position – thus if the rest position prescribed by activator does

not coincide with natural rest position, the retractive musculature

is stretched.

In Class II malocclusion, the construction bite of the Herren

activator dislocates the mandible ventrally, parallel to occlusal

plane by a total of 8mm or more. The improvement of post

normal occlusion was directly related to the amount of

mandibular displacement, in taking the construction wax bite.www.indiandentalacademy.com


When the activator is inserted, the mandible is purposely carried

forward until it is possible to bite completely in to the

positioning splint.

The mandible is kept from being retracted because the activator

takes the load of these forces and transmits them in an occipital

direction, to the maxillary dental arch.

Since “action equals reaction” a force of equal magnitude but

opposite direction acts against the mandibular dental arch.


The force acts continuously only as long as the Herren or L.S.U

activator is in place i.e. 9 – 10 hrs during night.

The activator holds the retractive musculature of the mandible

passively stretched.

More over, the activator inserted between the teeth and tongue

act as a shield that keeps the tongue away from the free way

space, which enables the eruption of the teeth, provided that the

acrylic occlusal stops of posterior teeth are ground away from

the appliance.


According to rat studies reported by Petrovic et al, the action of

Herren type of activator comprises a two-stage effect.

During the time the activator is worn, the protrusive position of

the mandible (caused by construction bite) causes reduced

increase in length of the lateral pterygoid muscle and at the same

time forms a new sensory “engram” for positioning of the

mandible.

This causes the mandible to function in a more forward position

during the period when the activator is not worn.

The forward positioning of the mandible by the contraction of

the lateral pterygoid muscle, when the activator is not being used

causes an accelerated growth rate of condylar cartilage. www.indiandentalacademy.com

Specific features

Twin arrowhead clasp.

Expansion screws.

Lingual springs to correct moderate incisal irregularities.

Extension of the flanges towards the floor of the mouth-mandibular anchorage(lower labial bow if needed)

Horizontal slot in maxillary incisors for comfort.

No pathologic changes in TMJ.

Asymmetrical Class II Div I- Expansion screws with asymmetric cuts in the appliance



Skeletal effect

To correct the class II malocclusion in an expedient, reliable and economic way.

To retard forward growth of the maxilla.

To reposition the mandible through mandibular growth, either in a horizontal or in a vertical direction.

To achieve these performances in the transitional as well as in the early permanent dentition, independent from the pubertal growth peak in body height( by over compensating)

To provide a high rate of stability of the treatment results after several years out of retention.


Herren activator holds the maxillary dental arch preventing the maxillary forward growth, the mandibular dental arch carried forward together with its basal arch.

The treatment results in,

Increase of SNB angle

Decrease of ANB angle

Mandible length increased (distance measured from middle of the external ear opening & gnathion– from cephalometric head films)

Change in position of the mandible, either a more forward or a more downward direction.


Dental Effect

Dentoalveolar compensation (distal movement of upper molars,

mesial movement of the lower molars) appeared to be inversely

related to skeletal adaptation.

The correction of molar relationship occurred to 55% by

skeletal changes.


Class II Div 2 malocclusions

Herren advocated expansion screws,lingual springs for correction of retruded incisors and guiding spurs to relieve minor crowding.


Class III Malocclusion


Retention

• Retention period - (due to over compensation) 15 months after

normal (neutral) dental arch relationships is achieved and overjet

is corrected.

• This normal dental arch relationship is maintained in taking the

construction wax bite for a retention activator. However the

mandible is carried forward by about 2 mm, beyond neutro

occlusion to compensate for the increase in overjet that occurs as

a result of rotation of the mandible around the condylar hinge

axis when a vertical inter occlusal clearance of 4 – 6 mm is

constructed.


Relapse

If, treatment started too an early age, partial relapse occur after

retention. It is recommend to start treatment, when premolars

have erupted.

Corrections of Antero-posterior basal discrepancy, resulting

from this therapy, were shown to be stable even 5 years after the

end of retention.


MODIFICATIONS OF ACTIVATOR


BOW ACTIVATOR The upper and lower halves-

connected-elastic bow. It is thus possible to change

the relationship of the upper and lower halves of the appliance.

With the treatment of class II division 1 malocclusion, beginning can be made with a small forward positioning, increasing this gradually by a periodic adjustment as recommended by Frankel.


Taatz (1971) ,

appliances specially suited for treatment of class II division 1 malocclusion in the deciduous dentition.

Small children will have the appliance in place for longer periods of time because they sleep more hours.

Young patients seem to adapt more easily to bringing the mandible forward gradually than to a sudden forward positioning.

Mixed dentition treatment is probably better from both a growth response and a patient compliance standpoint.


REDUCED ACTIVATOR OR CYBERNATOR

Resembles bionator

customary labial wire of the activator is used, as well as most of other simple appurtenances of this and other myofunctional appliances including the coffin spring.

Construction bite?

Advantages?www.indiandentalacademy.com

Spurs added to prevent the mesial movement of molars during

the shedding of deciduous molars.

Can be combined with fixed appliance therapy.

Headgear tubes can be incorporated for extra oral force.


U BOW ACTIVATOR

• maxillary and mandibular active plates, joined by a U bow in the region of the first permanent molars.

• In addition to acrylic covering of the lingual tissue aspects, gingiva and teeth, plates also extend over the occlusal aspects of all teeth.


The height of the construction bite is that of interocclusal space

or clearance with the mandible in postural rest for the karwetzky

appliance.

Thus space varies with the malocclusions.


U-bow :1 long leg ; 1 short leg .The shorter leg is imbedded in the upper appliance, whereas the longer leg is attached to lower plate.



Advantages

Combinations of different types of sagittal or transverse

screws, labial wires and springs enhance the basic appliance

action.

U-bow activator combined with fixed appliance when there are

severe rotations or there is need for selective extraction and

uprighting of teeth contiguous to extraction site.

Orthognathic surgery in adults like corticotomies and sub

apical resections, u bow activator has the potential for use.


PROPULSOR ACTIVATOR

hybrid appliance. Advantage? No wire configuration are used with propulsor, acrylic

connecting the upper buccal segment to the lower lingual flange also serves as occlusal support to stabilize the appliance


As treatment progresses this acrylic is removed progressively to

allow for unhindered eruption of molars and resultant reduction

of the deep overbites, if exists.

Also if selective eruption is desired to reduce the class II buccal

segment relationship by upward and forward eruption of the

lower teeth while preventing forward eruption of upper teeth by

removing acrylic in the opposing lower molar area leaving them

free.

The compliance is usually good because of the lightweight

&minimum bulk of the appliance.


CUT OUT (or) PALATE FREE ACTIVATOR

Advantage of the Bionator with some of those of the original Andersen – Haupl appliance.

Parts? www.indiandentalacademy.com

Metzelder changes however do have some advantages.

Appliance is easier to make.

It may carry all the appurtenances described for the activator.

These include

The jackscrew for expansion

Petrik finger spring for moving individual teeth. (upper&lower

canine after extraction).

Springs for labial tipping of lower incisors.

Proclining springs for Class II Div 2 cases.



Open Bite Class III


ELASTIC OPEN ACTIVATOR The elastic open activator

resemble the Bionator, with acrylic anteriorly and with more wires.

The Bionator though free movable in the oral cavity, is carefully stabilized on posterior occlusal surfaces or the lower incisors as the occasion demands.

completely lacks such stabilization and thus its vertical mobility in the mouth is unimpeded. www.indiandentalacademy.com

Mode of Action

The appliance will react to most of the tongue

movements and so it must "come to terms" with the

tongue.

In this manner, a great number of impulses are

transmitted to the teeth, serving as the basis for

transformative changes.


Standard EOA bilateral acrylic parts, an

upper and lower labial wire, a palatal arch and guiding wires for upper and lower incisors.

The acrylic parts extend from the canine posteriorly to the point just behind the first or second permanent molar if it is present.

The acrylic is quite thin in order to leave the largest possible space for the tongue. Stabilization of acrylic position is accomplished by means of contact with the lingual surfaces of maxillary and mandibular canines.www.indiandentalacademy.com

Relieve the crowding

To relieve the crowding of maxillary central incisors, half of maxillary labial wire was omitted, with the other half being used to engage the incisor. On this side, the guiding wire was used only for the opposite side.


Space maintainer

For example, the second

deciduous molar has been

lost prematurely. Its space is

maintained by an extension

of contiguous acrylic; with

the flat acrylic surface .a

double wire is placed mesial

to first molar and distal to

first deciduous molars.www.indiandentalacademy.com

Class II division 1 malocclusion

Construction bite

With an overjet as large as 10mm, it is usually possible to get the incisors in to an edge-to-edge bite.

No TMJ problems, even after such extensive forward positioning of the mandible.


• Class II division 2 malocclusion or Deckbiss


Class III mal occlusion

Construction bite

Edge to edge bite of the incisors or most retruded mandibular position.

The maxillary labial wire carries lip pads similar to those of Frankel appliance.


Unilateral cross bite Construction bite Bite with slight over

correction of the midline is advantageous.

The acrylic closely follows the teeth, except in mandibular part that approximates the teeth in cross bite.


Open Bite


Kinetor- Stockfish

Stockfish- Elastic activator- semi double plate appliance with latex tubing between the upper and lower components to stimulate function.

Elastic appliance-isotonic muscle contractions-less force magnitude-less effective.

Longer wearing time-efficient.


WUNDERER MODIFICATION OF ACTIVATOR FOR CLASS III MALOCCLUSION

The appliance is split

horizontally with the upper

and lower portion connected

by a screw that is embedded

in an acrylic extension of the

mandibular portion behind

the maxillary incisors.


As the screw is opened the maxillary portion moves anteriorly

with a reciprocal posterior thrust acting on the mandibular

dentition. Occlusal surfaces of the posterior teeth are covered

with acrylic to enhance retention.

The construction bite for class III case is taken in most retruded

or hinge axis position of the mandible with the incisal edges

2mmor 3mm apart.

In addition to maxillary labial bow a mandibular labial bow used

to guide the mandible distally as they occlude.www.indiandentalacademy.com

ACTIVATOR-HEAD GEAR COMBINATION


PFEIFFER-GROBETY A cervical headgear with a long

outer bow is used.

The inner bow is inserted into

buccal tubes attached to the

maxillary first molars and the outer

bow is adjusted to about 5° below

the inner bow.

This produces a predominantly

distal force through the center of

resistance of the molar teeth and a

lesser vertical extrusive force

component .www.indiandentalacademy.com

The neck strap produces a force of approximately 400 grams, measured unilaterally.

The activator used is based on the design and application described by Harvold and modified for use with a cervical headgear applied to the maxillary first molars.

Brachyfacial and mesofacial types responded most favorably to this combination.

This combination is contraindicated in dolichofacial type, because it results in mandibular clockwise rotation

Duration of wear- 14 continuous hours a day.


Pfeiffer and Grobety supported combination activator —

cervical headgear therapy., for two reasons:

to extrude maxillary molars, and

to apply orthopedic traction to the maxilla and an activator to

induce orthopedic mandibular changes, restrain maxillary

growth, and cause selective eruption of teeth.

Drawbacks?


STOCKLI-TEUCHER APPROACH

The inner face bow is completely embedded in the labial side of the maxillary splint, and the short outer arms are bent upward depending on the desired angle to the occlusal plane.

Torquing springs, jackscrews, lip pads Can also be incorporated.


Vertical control the untrimmed interocclusal acrylic

acts as a bite block. the inclination of the outer face bow

precise control over the direction of force, according to the following principles:

A force passing through the center of resistance produces pure translation in the direction of the force.

A force passing at a distance from the center of resistance generates a moment, with a combined effect of rotation (from the moment) and translation (from the force).www.indiandentalacademy.com

Duration of wear

Active treatment usually takes about 10 months, with the

appliance worn at night and for a few hours during the day (12-

14 hours total per day).


Stockfish & Hickam

Stockfish-Kinetor ( elastic activator ) with high pull headgear

attached to the buccal tubes in molar bands.

Hickam- Extraoral force applied to the hooks soldered to the

labial bow of the activator- control of the downward and

backward rotation of the maxilla and have a restrictive effect on

the horizontal and vertical maxillary basal and dentoalveolar

components.


Bass Appliance Neville (1987)- maxillary

splint, with an anterior expansion screw and an incisor torquing spring .

Lingual pads for mandibular growth enhancement are slotted into the splint, which also carries detachable side and labial screens.

The appliance system offers considerable flexibility in design, much as with an edgewise approach.



Trimming of the activator


Pinciples in Trimming The force is intermittent. This allows dynamic and rhythmic

muscle forces to act in such a manner that the appliance acts by

kinetic energy.

The direction of the desired force is determined by selective

grinding of the acrylic surfaces that contact the teeth.

The magnitude of force is determined by the amount of acrylic

that contact the teeth.

The acrylic surface that transmit the force and contact the teeth

are called guide planes

Evaluation?www.indiandentalacademy.com

VERTICAL CONTROL

INTRUSION OF TEETH:

Incisors: Can be achieved by loading

the incisal edges of teeth, the labial bow should be below the area of greatest convexity or on incisal third.

Molars: Performed by loading only

the cusps. The pits and fossas are cleared to eliminate any possible incline plane effect


Extrusion of teeth Incisors:

Requires loading the acrylic above the area of greatest concavity in the maxilla and below this area in the mandible. Although not effective can be enhanced by placing the labial bow above the area of greatest convexity.

Indicated in Open bite problems(finger sucking)


Molars:

Requires loading the acrylic above the area of greatest convexity in the maxilla and below this area in the mandible.

Indicated in deep bite cases.

Simultaneous extrusion of both the upper and lower buccal segments-no adequate conttrol.


PROTRUSION OF INCISORS

Incisors can be protruded by loading their lingual surface and screening lip strain by passive labial bow.

Entire lingual surface loaded

Incisal third of lingual surface is loaded.


Retrusion of Incisors

Acrylic is trimmed from the back of incisor

Active Labial bow is incorporated


MOVEMENT OF POSTERIORS IN SAGITAL PLANE Distalization: the Guide planes are

loaded in the mesio lingual surfaces.

Indicated in class II cases.


Mesial movement:

Can be achieved by loading the disto - lingual

surfaces.

Indicated for the upper arch in class III cases.


Movement in transverse plane

To achieve transverse

movement the lingual

acrylic surfaces opposite

to the posterior teeth

must be in contact with

teeth.

More effective expansion

can be achieved using

Jack screws. www.indiandentalacademy.com

Activator Trimming in Class II malocclusions

If upper incisors are to be retruded and the labial bow is active-

acrylic capping needed to prevent extrusion.

Lower incisor capping needed to prevent lower incisor

proclination.

Selective trimming of the acrylic that prevents mesial movement

of the upper buccal segments and enhances mesial movement of

the lower buccal segment- Class II correction.


Activator Trimming in Class III malocclusions

The upper incisors are loaded for protrusion and labial bow

passive.

Lip pads used instead of labial bow to stimulate basal maxillary

development.

Lower incisors are retruded-acrylic ground lingually ,labial bow

active.

Upper posterior teeth guided mesially and lower posterior teeth

guided distally- Class III correction.


Vertical dysplasia

Deep bite cases: The incisors are guided for intrusion and molars

for extrusion .The labial bow active and contacts the incisal third.

Open Bite cases: The incisor area trimmed for extrusion and the

molar area is intruded. The labial bow active and contacts the

gingival third.


Limitations of Activator Treatment…www.indiandentalacademy.com

appliance cannot be used by itself to correct crowding.

The appliance is not used in correction of Class I problems of

crowded teeth caused by disharmony between tooth size and jaw

size

Although the activator is effective in correction of overbite, it

does not routinely achieve such correction through the intrusion

of incisor teeth, but rather it permits the eruption teeth in the

buccal segments.

Because the teeth in the buccal segments are permitted to follow

their normal eruption paths and the incisor teeth are not

permitted to erupt; the effect of intrusion is achieved without

actually intruding the incisor teeth.www.indiandentalacademy.com

It is more likely that successful activator treatment coincides with

normal periods of active mandibular growth

Excessive LAFH and extreme vertical growth pattern.

Excessive procumbent lower incisors.

Nasal stenosis or chronic untreated allergy.

Non growing individuals.


Thought for the Day..!www.indiandentalacademy.com

Thank you

For more details please visit www.indiandentalacademy.com


Education

Activator and its modifications /certified fixed orthodontic courses /certified fixed orthodontic courses by Indian dental academy