FRANKEL’S FUNCTION REGULATORPHILOSOPHY & CONSTRUCTION BITE

CONTENTS

1. INTRODUCTION2. CLASSIFICATION3. BASIS OF FRANKLE’S PHILOSOPHY4. FRANKLE’S PHILOSOPHY5. TYPES OF APPLIENCES6. TIMING OF TREATMENT7. ACTIVATOR Vs FRANKLE8. FR-VTO9. CONSTRUCTION BITE

a. DIFFERENT TYPESb. TECHNIQUE

10.STUDIES 11.CONCLUSION

Dr.Rolf Frankle of Zwickau, GDR, introduced the concept of Function correctors, to the field of orthodontics in 1986 through the publications in Trans. Euro Ortho society.

Frankle based his philosophy upon HOTZ hypothesis.

Other names for Frankle’s appliance1. FUNCTION REGULATOR2. VESTIBULAR APPLIANCE3. ORAL GYMNASICS APPLIANCE

It is basically an exercise devise with its base of operation in vestibule.Other similar appliances are

1. Oral screen by Kraus 19562. MUHLEMAN-HOTZ propulsor

Frankle believed that full time wear was essential if any significant modification in orofacial musculature to be expected, different from Activator.

Charles Nord of Europe called it a “Revolution in Orthodontic appliances”.

CLASSIFICATIONI a. Tooth born passive: Activator, bionator, Twin Block b. Tooth born active : Modification of activator with

springs,screws. c. Tissue born passive: Frankle Fr.II Removable Functional appliance.

Fixed Functional appliance.IIIGroup I : These appliances transmit muscle forces directly

to the teeth for the purpose of correction of malocclusion. Eg: Inclined planes.

Group II : These appliances reposition the mandible & the resultant force is transmitted to the teeth & other

structures. Eg: Activator,Bionator.GroupIII : These appliances also reposition the mandible

But their area of operation is vestibule, outside the dental arch. Eg: Frankle’s appliance.

Schwartz classified orthodontic appliances According to degree of biologic efficiency(relationship between force magnitude & tissue response)I. First degree: Force below threshold of stimulation to activate orthodontic tooth movement.

Forces are…1. Short duration.2. Balance by compensatory forces like from cheek, lip and tongue.3. Forces of mastication are not artificially reinforced 4. Too weak to provoke tooth movement.

Frankel comes in this category.

II. Second degree: consider most favorable to achieve continuous tooth movement without root resorption.Forces are weaker than blood pressure 15-20 gm/cm2

They are effective when exerted in same directionPressure effective only over the distance of 0.1mm (half the

thickness of periodontal ligament)

II. Third degree: These forces interrupt the blood circulation of periodontal ligament (20-50).interrupted forces are conducive to resorption and deposition.

II. Fourth degree: Forces of such magnitude that tissues are crushed, Extensive necrosis is seen in them.

Basis of Frankle’s Philosophy Frankle recognizes the relationship between the form and function as the

biologic axiom. Establishment of functionally adequate space conditions in the orofacial

area constitutes an important factor in skeletal growth. Functional performance of muscular portions of capsule is important

It has space controlling potential

Frankle has given importance to the important process of deglutition while formulating his philosophy.Based on the experiments of Elekert Mobious (‘62) Frankle (‘67) and Pictone (‘75), he said

1. During vaccum is credited in oral cavity- due to anterior and posterior seal

2. As mandible returns to rest position after swallowing.

Decrease in interocclusal spaceBuccal forces on dentoalveolar structures.

Unbalanced by tongue

Great constricting effect on arches.

Frankel’s Philosophy1. Altering the function of soft tissue matrix, the form of skeletal

components can be redirected.2. Important muscles in the region

a. Orbicularis orisb. Buccinatorc. Mentalisd. Tongue

3. Abnormal perioral muscle deforming action on growth4. Natural interplay of faces, Albert abnormal must be screened

& modified.5. Vestibular construction an artificial “ough to be matrix

allow muscles to exercise and adapt (not push out from within).

6. Screening of “Constricting buccinator mechanism”

Causes intercanine expansion

Relieves lower anterior crowding.7. Promotes normal muscle function & eliminates

a. Lip trap.b. Hyperactive mentalis.

c. Aberrant buccinator/orbicularis oris.8. Frankel believed in full time wear.9. Roll of tongue.

He thinks it plays significant role in the ultimate outward progression of the teeth & investing tissues.

But also thinks that, its role has been overstressed. Much of its function may be compensatory or adaptive. Vaccum created during swallowing, offset the intrinsic

potential of the tongue.

Role of Anterior Oral Seal In patient with mouth breathing habit due to any previous condition & in hypoactive orbicularis oris, Frankel believed the anterior oral seal training as indispensable.

Mouth Breathing Patients:Air pressure conditions are beyond the physiological range.Incompetent lips are the pathophysiological condition at any rate.

Hypotonic Upper Lip:This may be due to severe Proclination of upper incisor.Mentalis activity is increased in compensation (hyperactive mentalis).Lower lip pads are provided to screen this hyperactivity & oral seal

training is encouraged.

Role of Periosteal Pull:In addition to screening action, vestibular shields and lip pad perform

this important function.These structures extend into the depth of the buccal & labial vestibule.Create tension in the tissueExerts tension on contagious Periosteal tissue.Increase bone activity in the region.Maxillary bone widened.Apical bone widening.

Bodily movement of buccal segment.

Sagital Correction Via Tooth Born Maxillary Anchorage.For appliance is anchored positively to the maxillary Arch. Anchorage is determined through wire between

1. Mesial contact point of both upper molars.2. Distal contact of both Upper canines.

Teeth are separated and wire pass below the contact area of this teeth.

FIGURE

If not anchored in the embrasure1. lower labial tipping may occur2. Injuring to labial gingival tissues in mandible may occur.

Differential Eruption Guidance Occlusal stops are given in Fr I &II in the maxillary molar

region. It prevents there eruption. Mandibular molar are free to erupt upward and forward. 1-2 mm of total 6-7 mm of Sagittal advancement may be

expected in terms of eruption. No wire contacts in the mandibular arch.

Sagittal correctionLingual bow with U loop – Fr IaLingual shield - Fr IbThese extend into floor of mouth to fit against lingual alveolar mucosa, which gives proprioceptive stimulus.

Effect on Maxilla It does have a restraining effect on maxilla and maxillary arch

McNamara indicates this is minimal. Lee Graber unpublished the study of 1993 Labial wire not activated.

In summery:- mode of action of Fr1. Increase in transeverse & Sagittal intraoral space.2. Increase in vertical space.3. Mandibular protraction.4. Muscle function adaption

Oral exercises recommended by Frankel1. Anterior oral seal2. Swallowing, speaking with appliance in place.

Frankel’s Philosophy1. Vestibular area of operation.2. Screening of abnormal muscle function.3. Full time wear.4. Role of tongue5. Role of anterior oral seal6. Role of Periosteal pull.7. Sagittal correction via tooth born maxillary anchorage8. Differential eruption guidance.

9. Sagittal correction – Lingual shields & U loops10.Effect on maxilla11.Role of muscles exercises

Timing of FRANKEL APPLIANCE Treatment.

1. Best time is late mixed dentition and transitional dentition greatest adaptational changes (but status of dentition)2. For Fr II After eruption of upper & lower anteriors 7 ½ - 8 years or 8 ½ - 9 yrs. If patient reports late wait for eruption of canine & premolars.3. For Fr III Early mixed dentition or deciduous dentition. (after eruption of all first molars.)4. For Fr IV Mixed dentition & continuing till permanent dentition.

Important points:- Patient development psychological & physiological- Dentition status firm teeth needed to anchor.

McNamara indicated 1 year prior to exfoliation of deciduous molars.

Frankel Activator

1. Acrylic parts outside 1. Its inside the archthe arch 2. Becomes Effective by 2. Being in contact withstanding away from arch. dentoalveolar arch.3. Operative by withholding 3. Operative by exerting pressure pressure.4. Eliminate the muscular 4. Harnesses the forces muscular forces.

Frankel believes that activator is not a true functional appliance because1. bone cells do not distinguish between source of pressure.(muscle or

appliance)2. any appliance exerting pressure on dentoalveolar structure is outside the

true definition of FUNCTIONAL STIMULI

The Fr- VTOThe clinical diagnostic test to determine whether functional appliance will be beneficial.A series of profile photographs are taken

I Photograph: patient in postural rest position.II Photograph: patient in habitual occlusion with lips relaxedIII Photograph: patient asked to protrude the mandible in correct Sagittal relationship. Overjet is reduced.

3 PHOTOGRAPHS.

Instant print can be used to motivate the patient.DIAGRAMS OFEFFECT OF BUCCAL SHIELDSEFFECTD OF LIP PADSCONCOMITANT EFFECT OF LIPPADS & BUCCAL SHIELDS Types of Function Regulators I . Fr 1

1. Fr Ia : Used for treatment of class I deep bite & class II division 1 with overjet <5 mm

2. Fr Ib : Used for class II division 1 with overjet<7mm & molars upto end-on relation

3. Fr Ib : Used in class II division 1 with overjet<10 mm.II. Fr 2 : Used in treatment of class II division 1&2III Fr 3 : Used for class III cases.IV. Fr 4 : Used for openbite cases & some class II division I cases & bimaxillary protrusion cases.

Classically Fr is given in non extraction cases but can be given in extraction cases also.

V. Fr appliances in cleft palate cases.VI. Fr appliances in Adults(McNamara)

Construction BiteDifferent opinion exert regarding the amount of horizontal and vertical opening.

1. For minor Sagittal problems: (2-4mm)Take bite in end-on relation of incisors.Frankel recommends mandibular advancement

up to 2.5 to 3mmVertical opening large enough to let cross over

wires pass throughAt up to 6 mm advancement, vertical opening is that at incisal edge to edge position.

2. If more than 6 mm of Sagittal advancement needed then 3 mm advancement is easily tolerated (step wise advancement). Vertical opening is still not beyond end-on bite.

3. For Frankel III appliance Clinically retruding the mandible as much as possible condyle occupying most posterior position in the fossa.Vertical opening limited to allow crossbite correction

Bite RegistrationFor Fr Ia,b,c & Fr II1. Ask the patient to protrude the mandible in desired position and hold it there for 3-5 mins

2. Repeat maneuver several times.3. Keep Midline correct.4. Practice construction bite may be used.5. For final practice bite, warm water is used to soften beeswax or horseshoe wafer.

Thickness – 2-4 mm more than desired bite thickness6. Patient asked to bite to desired position – Guided by the operator.7. Bite removal- chilled – placed on mould to check fit – excess removal with hot knife.8. Replaced in mouth- checked.

For Fr III1. Taken in retruded position of mandible.2. Clinician gently taps on the patient’s mandible with flexed knuckles

while patient opens bite 1 cm.3. Continue tapping gently and then ask patient to close slowly—guide the

mandible posteriorly.4. Place the thumb against symphysis & forefinger under chin to guide.5. Let patient hold mandible there for 1-2 minutes (proprioceptive learning

process).6. It is supposed to be an easier position to hold because of reproducible

terminal position wax can be softer.

Bite opening is kept minimum to allow lip seal.Deep bite cases need greater bite opening.

Frankel IV Vertical opening is kept minimal with a wafer of acrylic interposed between upper & lower buccal segment.

Technique of bite Registration

Steps:1. Separation2. Impression making

3. Bite Registration.

Separation Space to be created 1. Distal to upper deciduous canine. 2. Mesial to upper first molar.Special heavy separators should be placed 5-7 days before impression make.In case of inadequate space plan disking of deciduous upper canine & molars at the time of delivery of appliance.

Impression making.1. Critical step & more demanding – will reduce cast trimming2. Impression include whole alveolar process to the depth of sulci.3. Care to be taken – not to distort soft tissues & muscle attachments.4. Rebuilding of metal trays with utility wax.5. Preformed Styrofoam (disposable)inadequate6. Custom trays should be fabricated on stock metal tray.7. Thermal sensitive acrylic trays can be moulded.

FIGURE.

Clinical relevance of step by step mandibular advancement in treatment of mandibular retrusion using Fr appliance.

AIM: To evaluate skeletal & dental changes occurring during the treatment with Fr and to compare the results achieved in patients in whom the initial construction bite was taken step by step Vs edge to edge advancement.Sample: Group B 60 Children with Fr (step by step)

Group A 60 children with Fr (edge to edge) Ung 50 children with no treatment

Skeletal class II malocclusion <ANB 5.9º -6º

Early mixed dentition Treatment time – 14 months.

Pre & post treatment lateral cephalogram were taken.Occipital reference system for superimpositionMid Sagittal structures of occipital bone were taken as reference.Ventricaudal border of basal part & internal ridge of occipital bone.

2 FIGURE

Measurements

Positional changes of maxillary landmark.Positional changes in mandibular area.Angular changes.Dimensional changes of mandible

Results1. Patient A moved anteriorly 1 mm in untreated and Group b in group A 0.36mmPosition of Maxillary molarFr A -0.1mmFr B 0.6mmUNG 1.2mm

2. Movement of pogonionGrp A 1.6mmGrpB 2.5mmUNG 1.6mm

Vertically both Grp A & Grp B 3.4 - 3.2mm UNG 1.1mm

Position of Condyle in Glenoid FossaIn Grp B maintainedIn Grp A anteriorly positioned

3. Angular changes :IMPA, MPA, Gonial Angle Gonial Angle: 1.11 (GPA) (0.52º) GPB (-0.46º)UNG

GPA IMPA - 5.4º increased.GPB IMPA – 2.2º Increased.UNGIMPA – 2.0º Increased.MPA – GPA-1º GPB0.3º UNG- -0.5º

4. Dimentional ChangesGPA & GPB distance between Co/Ar to Pog inc. significantly

No significant inc. in corpus lengthening. Ramus length GPA – 0.6mm

GPB – 1.4mm

Discussion:1. Restricting effect on maxilla can be eliminated or reduced in step by

step advancement.2. GPA – Maxillary molar distally moved.

GPB – only restricted.3. Greater dentoalveolar changes in edge to edge bite.4. Condyle fossae position maintained.

Function Regulator Therapy for Cleft PatientsKerr et al – AJODO 1981

A Clp children exhibiting maxillary segment collapse and crossbites were treated with Fr for 6-18 months.Age 7-10 years with surgically repaired clefts of palate.Records: Intraoral & Extraoral photographs, lateral & Frontal Ceph. , dental casts, HRXg, Speech evaluation.Implants were placed prior to initial recordsInfrazygomatous implants Mandibular molar region.

Results:Interimplant distance was measured on PA Ceph. Between Lower first molars 0.79mm (Greatest mean change)Interzygomatic implant 1.79mm(Greatest)

-0.5 mm (least)Dental measurements

Maxillary canine Change (0.88± 1.08mm)Speech affected in 1st week of wear but came back on long term wear.

Conclusion: Minimal transeverse skeletal, dental changes in maxilla or

crossbite relationship Not useful incase where treatment objective is primary expansion

of collapsed maxillary segments. Can be used as a retention appliance after primary expansion of

maxilla. No significant effect on spech on long term.

The effects of Fr 4 therapy on the treatment of angle class I skeletal anterior openbite malocclusion Erbay et al AJODO 1995

AIM: To study the effects cephalometrically, in the Sagittal & vertical planes of Fr 4 appliance and lip seal training for the treatment of angles class I skeletal anterior open bite malocclusion.

Material And Methods: 40 turkish children with angles class I skeletal open bite (13 girls & 17 boys) characteristics: Mixed dentition stage(7.8-9.3 yrs)

Angles class I molar relation Anterior open bite of atleast 1 mmSteep MPA(SN-GoMe>37º)

2 groups were made.1 Control Group 2. Treated Group

Treatment duration :- 2 years

In treated Group – 18 hrs of appliance wear with lip seal training.

Lateral cephalogram analysis done by single investigation 14 linear, 13 angular, 2 ratio were measured Important findings:

A cephalometric, tomographic and dental cast evaluation of Frankel therapy.

Hamilton et al AJODO 1987

Aim : To study skeletal, dental and condylar positional changes induced by Fr2 therapy.

25 cases with cephalographs, dental casts and CTscan (Pre & post treatment) were taken.10 boys & 15 girls.

Mean ANB 5.6º & full dental classIIMPA - 25º or less mean -19.6ºAngle IMPA 94º-95ºTreatment time: about 2 years.Changes were compared with normal subjects aaaaat University of Michigan.

Results:1. AP Skeletal correction - Slight decrease in ANB upto 1º than normal - Normal mandibular growth of 2 mm/yrs was noted.2. Mandibular Rotation.A small increase in MPA upto 1º was noted.3. Facial height.

Cephalometric DataAP skeletal measurement:

- little significant effect on AP Growth pattern - slight decrease in ANB- Normal mandibular growth noted 2mm/yr.

Mandibular Rotation:Small increase in MPA(0.4º)

Facial height:No significant increase in facial height.

Incisor Position: Significantly Greater than normal retraction (angular) -4º and -1.0

mm (bodily)

No significant upper incisor extension was noted. Lower incisors proclined 1.5 mm & 2.2ºMolar Position:

Slight intrusion of maxillary alveolar height (-0.6mm) was noted.Dental cast data:

Intercanine width Dist. Between lower canines is1.6 mm inc(significant & more than 1.3m more than control)

Dist. Between Upper canines is not statistically significantly inc as compared to control.

Conclusion:1. Frankel believed in Moss therapy and a true “functional stimuli”

concept.2. His theory of appliance is quite different from activator. Bionator may

resemble in some modes of action.3. Indicated in mixed dention for maximum adaptational change.4. Classically used for nonextraction cases.5. Believes in full time wear.6. Step wise advancement of mandible7. Concentrates on expanding oral functioning space to let the mandible

translate down & forward.