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Early myofunctionalapproach to skeletalClass II

Introduction

Therapy aimed at skeletal Class II subjects is carried out at theOdontology Clinic of Milan University in accordance withstudies conducted by Petrovic and Stutzmann (12, 13), with aninitial orthopaedic phase focussing on condylar growth. Such atherapeutic phase is made to coincide with the peak ofpre-pubertal growth, which we have identified by evaluatingskeletal age by X-raying the wrist and hand, following themethod according to Gianní (5). This is performed for the pur-pose of obtaining the greatest possible growth period, coupledto an acceptable duration of therapy.

This ideal age to start treatment corresponds, in our studies, tonine years of age plus or minus one year. Younger children alsocome to be observed, mainly through the screening visit thatthey undergo at about six years of age (the onset of change ofdentition). During this phase, although treatment is mainlydirected towards identifying cross-over bite and resultingasymmetries (interceptive orthodontics), a large number ofskeletal Class II children are noticed whose orthopaedictherapy is postponed until they reach nine years of age. A large

original work

C. QuadrelliM. GheorgiuC. MarchettiV. Ghiglione

University of Studies of Milan

Clinic of Odontology and Stomatology

Institutes of Clinical Professional

Specialization

Director: Professor F. Santoro

Division of Clinical Orthognatodontics

And Electromyography

Head of Department: Professor V. Ghiglione

Key Words:

Skeletal Class II

Early treatment

Soft tissues dysfunctions

Abstract - Early myofunctional approach to skeletal Class II

We analysed the effects of the Pre-Orthodontic Position Trainer in skeletal development,

muscle function, tongue function, breathing and bruxism in skeletal Class II patients. This

one-year therapy prepares for usual orthopaedic Class II treatment in patients with soft tis-

sue dysfunction or bruxism and should be adopted before peak pre-pubertal growth; the

ideal age is 4 - 9 years.

The results of the treatment were analysed by means of clinical, radiological, electromyo-

graphical, kinesiographical, stabilimetric and rhinomanometric evaluations and the meas-

urement of arch diameter using plaster models. The cases described in this pilot study

demonstrate the efficiency of this early myofunctional therapy in patients in skeletal Class II.

MONDO ORTODONTICO 2/2002 109

number of skeletal Class II dismorphosis alsodisplays disorders or parafunctions of the softtissues of the stomatognatic apparatus.

These cases have been classified into tworeasonably homogenous groups:

• the first, Group A, is characterised by:skeletal Class II, dentoalveolar open bite, lin-gual malposition and atypical deglutition;

• the second, Group B, is characterised by:skeletal Class II, dentoalveolar deep bite andbruxism.

Both groups are composed of patients withnon-obligatory oral respiration.

It was decided to subject these two groups toear ly pre-or thopaedic t reatment a imed atresolving dysfunctions through gentle, butactive, inducement of the protruding mandibu-lar position (14, 15). Our aim was that ofevaluating with ex adiuvantibus criteria theclinical efficacy of this early intervention, towhich this pilot report refers.

In future, these patients will be compared, forevaluation purposes, after classic orthopaedicClass II treatment, with patients havingreceived only Class II orthopaedic treatment atthe age of nine, plus or minus one year. Thepurpose of this practice is to also evaluatestatistically and not only from a clinico-empir-ical point of view, the efficacy of this earlytherapeutic approach.

At the same time, the purpose of this prelimi-nary report is to highlight possible relation-ships between skeletal Class II, dysfunctionsof the soft tissues, parafunctions, oral respira-tion and the general posture of the subject.

Electromyography, Stabilimetry,Rhinomanometry

A qualifying characteristic of the approach toorthodontic patients is that of defining a diag-

nosis and treatment plan, with particularreference to function, while consideringdentition not only within the mouth, but alsoin relation to other organs and systems, inadherence to Gianní’s indications (5), so tofollow a holistic approach to the patient. Forthis reason, we consider appropriate the useof electromyography, stabilimetry and rhino-manometry, particularly during the patient’sgrowth period when the correct relationshipbetween the various systems acquires signifi-cant importance in the control of growth ofthe stomatic structures (10).

The balanced development of the transversediameter of the upper jaw, for example, ispositively influenced by correct nasal respira-tion (16), hence the necessity of evaluatingthis function through rhinomanometry.

A properly designed therapeutic plan shouldthus take into account the possible need toreprogram respiration from oral to nasal.

Muscles inserted into the maxillary bone mustfunction correctly for normal development ofthis bone. The active movement of themandible by the external pterygoid muscles isdetermined by activating condylar growth (12).

Elect romyography a l lows detec t ion ofpossible muscular malfunctions and puttingcorrective treatment into place. Furthermore,electro-myography allows to determinewhether a brace to correct the mandibularposition stimulates the external pterygoidmuscles and whether it will be useful inencouraging condylar growth.

Stabilimetry allows the detection of overallpostural improvements whenever an interven-tion is made to regularise the balanced growthof the maxillaries.

It is also quite probable that the correction oforal respiration could contribute, by normalis-

C. Quadrelli, M. Gheorgiu, C. Marchetti, V. Ghiglione

110 2/2002 MONDO ORTODONTICO

ing the function of the relevant muscles, toimprove the general posture and not only thegrowth of the maxillaries.

Taking the above into consideration, wethought it opportune to intervene in skeletalClass II anomalies before the age of peakgrowth, until now considered the most suitablefor solely activating condylar growth.

Pre-Orthodontic Position Trainer

It was decided to initiate Class II orthopaedictherapy not only at an earlier age, but also aim-ing to correct functional problems concerningsoft tissues, such as lingual malposition, thecentripetal thrust of lips and cheeks, as well asoral respiration and bruxism. To this aim, ourattention was drawn to the Pre-OrthodonticPosition Trainer (fig. 1), a functional deviceusable in children from the age of four to tenyears and recommended for correcting:

– the interposition of lips between dental arches;

– atypical swallowing;

– the centripetal thrust of cheeks upon thedental arches;

– to discourage oral respiration;

– to avoid bruxism;

– to favour the action of the externalpterygoids and thus encourage the active pushof the mandible.

Therefore, the trainer encourages transversalbone growth (7, 11) by acting as a “shield” forthe cheeks; it brings about muscular relaxationand protection of teeth and articulations frombruxism, by virtue of the “bite effect”. Itdetermines the correction of skeletal Class IIthanks to active mandibular forcing and bydistancing the lower lips from the dental alve-olar arch it prevents malpositioning of the

tongue and lower lip during swallowing, thussolving the associated dental open bite. It alsopromotes nasal respiration.

Material and Methods

Clinical CasesSix children have been treated, four boys andtwo girls, ranging in age from four years andnine months to nine years and one month. Threechildren, affected with skeletal Class II, dentalalveolar open bite, lingual malposition, atypicalswallowing, non-obligatory oral respiration,were classified as Group A. Three children,displaying skeletal Class II, First Division, deepdental alveolar bite, bruxism and non-obligato-ry oral respiration, were classified as Group B.

Diagnostic Criteria

The following were used as diagnostic criteria:

1) Standard objective examination, as at thescreening visit adopted for the sixth year of age

2) Orthopantomography, latero-lateral telera-diography of the cranium and radiography ofthe wrist and hand to determine skeletal age,according to Gianní (6).3) Electromyography (fig. 2). Recourse to asurface electromyography (3) permits thescrutiny of muscular function through therecording of electrical potentials generated bythe simultaneous contraction of a number ofmuscle cells, defined as the potential of themotor unit. Every change in nerve or musclefibres induces a change of that potential of themotor uni t . Studies of experimental andclinical electromyography have demonstrateda linear relationship between the tension of amuscle in isometric contraction and thevoltage produced. This voltage is proportional


Class II Skeletal



to the tension of the muscle and also to thenumber of motor units called into play. It thusfollows that the voltage measurement derivedfrom one muscle represents a reliable indexrelating to the efficiency of that muscle or,more precisely, of the number of motor unitscalled upon by that muscle to obtain a con-traction. As muscle fatigue reduces the con-tractile efficiency of the motor units, the

fatigued muscle must recruit additional motorunits to perform the same amount of work, thusproducing additional current. Also, muscles inspasm (pathological isometric contraction)recruit an increased number of motor unitsbecause the fibres in spasm are not availablefor a physiological isotonic contraction.The electromyography employed consists of aneight-channel preamplifier, with filters to iso-late the patient from possible current disper-sions through the power supply. The channelsare connected to corresponding cutaneous elec-trodes thus enabling the simultaneous recordingof the electrical activity of four or eightmuscles (masseter, anterior and posteriortemporals and digastrics). Furthermore, a maincomputer with microprocessor is capable ofconverting the data relative to the electricalactivities of each muscle explored from ana-logue to numeric. A printer provides a hardcopy of the data in both graphic and numericform. Electrical potentials are gathered by

Fig. 1a, b - Pre-Orthodontic Position Trainer: 1) guide for tooth alignment; 2) protection against malposition of lips and

cheeks; 3) guide for the proprioceptive localization of the tongue; 4) protection against lingual malposition; 5) lip

bumper; 6) double groove into which the teeth can be placed while lips are closed to prevent oral respiration. Also

gives protection in cases of bruxism.

Fig. 2a, b - Surface electromyography.

1a 1b

2a 2b


Class II Skeletal

means of adhesive electrodes using an electro-conductive gel. The methodology described isderived from that structured by Jankelson (9,10).

4) Kinesiography with the kinesiograph inter-faced to the electromyograph (4,9) (fig. 3).The specialised software used is capable ofevaluating both the muscular condition andthe kinematics of the patient’s mandible. It isspecifically used to investigate the patient’smandible and at the same time to evaluate theideal trajectory of myocentric occlusion (idealphysiological occlusion that occurs in theabsence of muscular spasm). The kinesiographcan measure movements in aperture, closure,laterality, protrusion and retrusion of themandible, in the three spatial planes. It canalso allow the study of velocity by exploringthe principle of magnetic fields. To this aim, asmall magnet is secured with special adhesiveat the level of the central inferior incisors andmade to act within a preset magnetic field.Magnetic field variations, caused by the mag-net following the movement of the mandible,are recorded by sensing equipment securedaround the patient’s face. The millimetregraduated screen of an oscilloscope displays a

trace corresponding to the movement of themagnet in the preset magnetic field, allowingthe localization of the incisive mandibularpoint. Through a kinesiographic examination,it is possible to assess dysfunctions, record theideal neuromuscular occlusion and thediscrepancy between the latter and the normalcentric occlusion, always in adherence withJankelson’s indications (9, 10).

5) Rhinomanometry (2, 6, 8) basal and afterexertion to distinguish obstructions of ananatomic nature from those of inflammatorynature (fig. 4).

6) Stabilimeter readings (1) with open eyes,with closed eyes and during deglutition onstabilimeter support (fig. 5).

7) Measurement of intercanine cusps (cusp tocusp) and intermolar cusps (from mesiobuccalcusp to the cusp of the first molars) of theupper arch (7, 11).

Therapeutic Methodology

The Pre-Orthodontic Position Trainer was theappliance used.

For Group A the soft “blue” type, for Group Bthe hard “red” type, but not used in succession,

3 4 5

Fig. 3 - Kinesiograph

Fig. 4 - Rhinomanometer

Fig. 5 - Stabliometric Platform



as dental alignment was not sought as recom-mended by the manufacturers. Dental align-ment does not concern us during thistherapeutic phase. Therapy was carried out fora year, with the appliance worn all night andafternoon for an overall total of sixteen hoursper day. An additional series of simplemyotherapy exercises repeated ten times, withthe Pre-Orthodontic Position Trainer fitted,were carried out in the morning, afternoon andevening. The exercises consisted of:

1) positioning of the tip of the tongue on thelingual support of the appliance, closing lipsand swallowing while holding the appliance inplace;

2) with the tongue still in the positiondescribed above, closing the lips and breathingthrough the nose;

Results

Diagnosis

The following observations can be extrapolat-ed at diagnostic level:

1) Scan 9 in electromyography displays thatGroup A shows, at rest, higher potentials intemporals than in the masseters and reducedelectrical activity in the masseters in absolutevalues, thus hypotrophic. Scan 11 shows,during functional activity (alternate clenchingand relaxation of the mandible in habitualocclusion, followed by the same actions oncotton rolls), a low electrical output but withsufficient permanence in time. Electricaloutput is greater on the rolls, a sign of alteredvertical dimension. Group B has typically, andhere more markedly, an inversion of electricalvalues with a predominance of the temporalsover the masseters, that however have normalelectrical output at nominal values, thus

normotrophic, and an equal force on both thecotton roll and in habitual occlusion, a sign offree interocclusal space not being correct.

2) The kinesiographic exam highlights averticality defect, evident in Group B, withloss of free interocclusal space.

3) Rhinomanometry shows a scarcely signifi-cant behaviour, with normal patency or modestreduction of patency of the nasal fossae in allcases, but marked in one. However, improve-ment occurred during the stress test showing,in this case, the absence of actual anatomicobstructions, but only problems of an inflam-matory nature. Also with reference to casehistories, previous inflammatory episodes ofthe upper respiratory tract are found,particularly in children between the years ofthree and seven, coincident with school age.

4) The stabilimeter exam does not reveal spe-cific pathological alterations of the overallposture, except in one case, where changesseemed attributable to the position of themandible. However, in all cases, a certainnon-specific difficulty to maintain verticalforces on the projection of the centroid arenoticed and a wide and irregular bundle ofoscillations is displayed, meaning the centreof the mass is somewhat lateralized.

TherapyAt therapeutic level in both groups, normal-ization of the dental skeletal Class, withimprovements of the skeletal class, withaverage reduction of the ANB angle of 1.5º. InGroup A closure of the dental open bite isachieved, while Group B shows a slightimprovement of the overbite. The dento-skele-tal improvement appears more noticeable inGroup A cases with open bite due to lingualmalposition. The electromyography empha-sizes, for Group A, a normalization of valuesin Scan 9, with an increase of potentials


Class II Skeletal

generated by the masseters and an improve-ment of contraction force during habitualocclusion as compared to the contraction onthe cotton roll of Scan 11.Scan 20 shows normalization of the functionof the suprahyoid muscles used in physiologi-cal deglutition, with symmetric potentialswithin the norm of absolute values. Group Bshows a reduction of potentials generated bythe temporals and a normalization of therelationship between temporals and masseters.The physiological prevalence of the latter isthus proof of results obtained on bruxism.The kinesiographic exam of Group B displaysnormalization of interocclusal free space. Rhinomanometrics do not show noticeableimprovements. Stabilimeter readings showimprovement in maintaining the baricentreposition on the vertical plane for both groups.Measuremt of diameters of intercanine andupper intermolar shows an increase in the latter.

Discussion

The clinical and instrumental evaluation of thetwo groups of patients confirms that therapyof Class II patients having soft tissue dysfunc-tions or parafunctions show improvement afterusing the Pre-Orthodontic Position Trainerfor one year. The following is achieved:1) Normalization of the muscular function,evident and complete in both Group A and B,together with resolution of atypical deglutitionand control of bruxism;2) Improvement of the dental structure.Evident and significant in Group A withclosure of open dental bite. Less marked inGroup B with reduced aperture of bite andimprovement in tooth crowding;3) A modest result at skeletal level, medianreduction of the ANB angle of 1.5º, compara-ble in Groups A and B;

4) Unchanged patency in the nasal fossae, butimproved aptitude towards nasal respirationwith respect to non-obligatory oral breathing;5) Influence upon the overall body posture:improved capability to maintain the projectionof centre of mass on the vertical;6) Intercanine and intermolar diameters:increased only in the intermolars with modestimprovement of crowding of frontal teeth,when of a significant degree.

Conclusions

This study is a preliminary report the purposeof which is to clinically evaluate the therapeu-tic efficacy of the Pre-Orthodontic PositionTrainer. The subjects analysed here, after fur-ther Class II orthopaedic therapy with rapidexpansion of the palate and mandibularimpulsion, will serve as cases for comparisonwith controls treated only with Class IIorthopaedics and not preceded by the Pre-Orthodontic Position Trainer phase. Theclinical results illustrated above lead us tobelieve that it would be correct to bringforward by a year the therapy specificallyaimed at eliminating those dysfunctional andparafunctional factors of the soft tissues thatcan interfere with the mandibular growth andpromote correct deglutition, correct nasalrespiration and elimination of pathologicalmuscular contractures. The device is welltolerated by small patients, does not requirecollaboration different from that necessary fora common brace and requires fewer speechtherapy sessions. As a result, the trainerdelivers patients ready to start Class IItherapy, free from muscular dys func t ions o rpa ra func t ions , a l r eady accustomed to aprolonged and active posture of the mandible.Furthermore, this intervention would seem



appropriate in preventing abnormal posturalattitudes of the face typical of skeletal Class II.

Clinical Cases

Case number 1 (Group A)

Male patient MM of seven years and eightmonths, of skeletal Class II (fig. 6a), ANB angleof 11.2º (fig. 6b), infantile deglutition, lingualmalposition, open dental bite with a OVB of -0.7 mm and moderate dental crowding.

The electromyography shows (Fig 6d) areduction of the contractile force of the mas-seters, displaying a hypotrophic nature, and animproved recruitment of fibres during contrac-tion on the cotton roll with respect to that inhabitual occlusion.

Rhynomanometrics show normal patency of thenasal fossae (fig. 6e), though in the presence oforal respiration, is interpreted as an abnormalhabit following repeated episodes of inflamma-tion of the upper respiratory track in the past.

Stabilimeter output (fig. 6f) measurements arewithin the normal range although difficulty isshown in keeping the projection of the centre ofthe mass on the vertical.

Therapy lasted from December 1999 toFebruary 2001 and was carried out with thePre-Orthodontic Position Trainer (colour blue,soft) (fig. 1) worn for about sixteen hours a dayand in association with myotherapy exercises.

Final examinations show a more harmoniousprofile (fig. 6a), reduction of ANB to 9.8º(fig. 6b), gain of the OVB up to 0.6 mm,closure of the dental open bite and improve-ment of the molar and canine class (fig. 6c).

Electromyography displays in Scan 9 normal-ization of the absolute values of the potentialsgenerated by the masseters, which also appearnormotrophic, with physiological dominance of

the masseters over the temporals. Scan 11reveals normalization of the capability ofrecruitment of fibres in contraction duringhabitual occlusion, force that now prevails overthat of contraction over the cotton roll (fig. 6d).The suprahyoids, and particularly the digastrics,appear symmetrical with normal potentials inabsolute value in Scan 20. This corresponds toattaining a normal physiologic deglutition.The rhinomanometric examination appears tobe substantially unchanged except for a veryslight improvement in the patency of the nasalfossae (fig. 6e). Stabilimetry reveals that thecentre of the pressor force of the feet can besuperimposed on the centroid of vertical forces(fig. 6f). Measurements on the plaster modelsshow an increase only of the upper intermolardiameter of 1.5 mm, with that of the upperintercanine unvaried.

Case number 2 (Group B)

Female patient GG, of nine years and onemonth, of skeletal Class II (fig. 7a), ANBangle of 6º (fig. 7b), deep dental bite withOVB equivalent to 6 mm, marked crowdingborne by the incisors (Fig 7c) and bruxism.The electromyography shows in Scan 9predominance of hypertonic temporals overthe masseters, also hypertonic, a situationcompatible with deep bite and bruxism, whileScan 11 shows that biting on the cotton rollgenerates an increased electrical outputgreater than the norm and equal to theelectrical output during closure in habitualocclusion. This denotes incorrect freeinterocclusal space, with a possible loss offree interocclusal space. Predominance of thetemporals remains (fig. 7e). Rhinomanometryshows obvious obstruction of flow with reducedpatency of both nasal fossae (fig. 7f).Stabilimetry shows irregularity in the ball ofthe foot with difficulties in maintaining the


Class II Skeletal

Fig. 6a-f - Patient MM. a) profile before and after therapy;

b) cephalometric diagram before and after therapy; c)

overject and dental overbite before and after therapy; d)

electromyography before therapy, Scan 9 and Scan 11;

and after therapy, Scan 9, 11; e) rhynomanometry before

and after therapy; f) stabilimeter measurements before

and after therapy.

6a

6b

6c

6d

6d

Fig. 6a-f - Patient MM. a) profile before and after thera-

py; b) cephalometric diagram before and after therapy;

c) overject and dental overbite before and after therapy;

d) electromyography before therapy, Scan 9 and Scan

11; and after therapy, Scan 9, 11; e) rhynomanometry

before and after therapy; f) stabilimeter measurements

before and after therapy.



6d

6e

6f


Class II Skeletal

Fig. 7a-f - Patient GG. a) profile before and after thera-


c) overject and overbite before and after therapy; d)

electromyography before and after therapy; e) rhyno-

manometry before and after therapy; f) stabilimeter

measurements before and after therapy.

7c

7d

7b

7a

Fig. 7a-f - Patient GG. a) profile before and after thera-


c) overject and overbite before and after therapy; d)

electromyography before and after therapy; e) rhyno-

manometry before and after therapy; f) stabilimeter

measurements before and after therapy.

7d



7e

7f

projection of the centroid of the mass on thevertical (fig. 7e) even though the results arewithin the norm.Therapy lasted from September 1999 to March2001 using the Pre-Orthodontic PositionTrainer (colour red, hard, for bruxism) worn forsixteen hours a day, together with specificmyotherapy exercises.Final examination shows: improvement ofskeletal Class II with more regular profile(fig. 7a), and reduction of angle ANB to 5º(fig. 7b).Improvement of the occlusal relationship atcanine and molar level, but modest effect oncrowding and reduction of the OVB to 5 mm(fig. 7c).Electromyography (fig. 7d) shows in Scan 9 thenormalization of the temporal/masseter rela-tionship, with physiologic prevalence of themasseters. This suggests that control over brux-ism has been obtained. Scan 11 displays a dropin closure force upon the cotton roll as com-pared to that needed for habitual occlusion,indicating a probable recovery of physiologicinterocclusal free space.Rhinomanometry does not show improvements(fig. 7e).Stabilimetry demonstrates perfect centering ofthe projection of the centroid vertical forcesupon the vertical plane, in perfect coincidencewith the centre of pressure of the feet (fig. 7f).Measures on plaster models do not show anincrease of either the intercanine or the intermo-lar diameter and no improvement of dentalcrowding is apparent.

SummaryThe effects of the Pre-Orthodontic PositionTrainer on the stomatognatic system in Class IIwith soft tissue dysfunctions or parafunctions area n a l y s e d . T h e t h e r a p y, l a s t i n g o n e y e a r,

precedes and prepares for normal Class IIorthopaedic therapy and is carried out at anearlier age coincident with the pre-pubertalgrowth peak. Ideal age is between four and nineyears of age.

The results of the treatment are analysed bymeans of clinical, radiological, electromyo-graphical, kinesiographical, stabilimetrical,rhyno-manometric evaluations and measurementsof arch diameters using plaster models. The pilotcases, described and commented on, show theefficacy of carrying out a myofunctional thera-peutic approach on skeletal Class II subjects atan early age.

Key Words

Skeletal Class II

Early treatment

Dysfunctions of soft tissues and parafunctions

Bibliography

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12. Petrovic A, Stutzmann J. (Le musclepterygoidien externe et la croissance ducondyle mandibulaire. Recherchesexperimentales chez le jeune rat.)The external pterygoid and developmentof the mandibular condylar. Experimentalresearch among young rats. Orthod Franc1972; 43: 271-8.

13. Petrovic A, Stutzmann J. (Stimolazionedi crescita della mandibola umana indottaortopedicamente. Nuovi approcci alladecisione clinica) Orthopaedically inducedgrowth stimulation of the human mandible.New approaches to the clinical decision.XIV Congresso Sido Internazionale Venezia,22-25 ottobre 1987.

14. Quadrelli c, Ghiglione V, Marchetti C.(Relazione tra postura, disfunzioni dei tessutimolli dell’apparato stomatognatico, respi-razione e occlusione nel trattamento precocedelle II Classi scheletriche.) Relationshipsbetween posture, dysfunctions of the softtissues of the stomatognatic apparatus,respiration and occlusion in early treatmentof skeletal Class II. Congress “Occlusion andPosture; new Trends and New Problems”.Milan June 2001.

15. Quadrelli C, Ghiglione V, Gheorghiu Met alia. (Relazione tra postura, disfunzionedei tessuti molli dell’apparato stomatognati-co, respirazione e occlusione nel trattamentoprecoce nelle II Classi scheletriche.)Relationships between posture, dysfunctionof soft tissues of the stomatognatic apparatus,respiration and occlusion in the earlytreatment of skeletal Class II. XVI NationalCongress Sido, Genoa 26-27 October 2001.

16. Ung N, Koenig J, Shapiro PA et alia. Aquantitative assessment of respiratory patternsand their effects on dentofacial development.Am J Orthod Dentofac Orthop 1991; 98.

Received in editorial office October 2001Carlo QuadrelliVia Bixio 421013 Gallarate (VA)tel. 0331 777261 - 305422fax. 0331 777261e.mail: [email protected]

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