the herbst appliance: research- based updated clinical...

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BBased on the “bite jumping” idea introduced byKingsley in 1877, Emil Herbst developed his

appliance in the early 1900s and presented it for thefirst time at the International Dental Congress inBerlin in 1909. Twenty-five years later, in 1934,Herbst wrote about his experiences with the appli-ance in 3 articles. After that time, very little was pub-lished about the subject until Pancherz reintroducedthe treatment method in 1979.

Inititally, Pancherz used the Herbst bite jumpingmechanism as a scientific tool in clinical-experimen-tal orthodontic-orthopedic research. Through theyears, however, it became obvious that the appli-ance is most useful in the therapy of severe Class IImalocclusions. In comparison to conventional func-tional appliances (eg, activator, bionator, Fränkel),the Herbst appliance has several clinical advan-tages: The appliance is (1) fixed to the teeth, (2)works continuously 24 hours a day, (3) does notinterfere with speech, and (4) requires no patientcompliance to attain the desired treatment effects.

In 1979, Pancherz used a banded design of theHerbst appliance with a simple anchorage system. Inthe maxillary dental arch, the anchorage units oneach side comprised the first premolar and the firstpermanent molar connected to each other by a lin-gual sectional arch wire. In the mandibular dentalarch, the first premolars were interconnected by alingual arch wire touching the lingual surfaces of theanterior teeth. The telescoping tube was attached tothe maxillary molar band and the plunger to themandibular premolar band (Figs 1a and 1b).

In 1982, the anchorage system of the bandedHerbst appliance was changed. In the maxilla, thecanines and the incisors were incorporated into theanchorage unit by placing brackets on the teeth andconnecting them to the premolar bands with a labialsectional arch wire. In the mandible, the lingual archwire was extended to the first permanent molars,which also were banded (Figs 1c and 1d).

In the modern Herbst appliance, which has beenused on a regular basis since 1995, most teeth inthe maxilla and mandible are incorporated into theappliance for maximum anchorage. The bands havebeen replaced by cast splints of cobalt-chromiumalloy covering the teeth in the lateral segments. Addi-tionally, the maxillary and mandibular anterior teethare incorporated into the anchorage unit by connect-ing them to the splints with labial sectional archwires. The axes for the telescoping tube and plungerare soldered to the splints in the region of the maxil-lary first permanent molars and the mandibular firstpremolars, respectively (Figs 1e and 1f). The splintsare fixed to the teeth with a glass-ionomer cement.

The Herbst Appliance: RThe Herbst Appliance: Researesearch-ch-Based UpdatBased Updated Clinical Ped Clinical Possibilitiesossibilities

Hans Pancherz, DDS, Odont Dr1/Sabine Ruf, DDS, Dr med dent2

Aim: To focus on the efficacy of the Herbst appliance in the treatment of Class II malocclu-sions that otherwise would have been difficult without tooth extractions or orthognathicsurgery measures. Methods: Evidence-based study and review of our recent clinical,cephalometric roentgenographic, and magnetic resonance imaging research. This researchreveals that growth modification with the Herbst appliance is successful in older Class IIpatients, who are generally considered unresponsive to therapy with removable functionalappliances. Conclusions: We suggest a change in the current concept of Class II treatment,with growth adaptation through use of the Herbst appliance in children, adolescents, post-adolescents, and young adults. World J Orthod 2000;1:17–31.

1 Professor, Department of Orthodontics, University of Giessen,Giessen, Germany

2 Associate Professor, Department of Orthodontics, University ofGiessen, Giessen, Germany

REPRINT REQUESTS/CORRESPONDENCE

Prof Dr Hans Pancherz, Department of Orthodontics, University of Giessen, Schlangenzahl 14, D-35392 Giessen, Germany. Tel: +49 641 9946120. Fax: +49 641 9946119. E-mail: [email protected]




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Pancherz/Ruf WORLD JOURNAL OF ORTHODONTICS

In comparison to the banded Herbst appliance, thecast splint appliance has many advantages: It has aprecise fit on the teeth, is strong and hygienic, andsaves chair time because it is easy to insert andcauses few clinical problems (no broken bands).

Due to the higher laboratory costs of the cobalt-chromium splints, acrylic splints have been advo-cated by some clinicians. However, acrylic splints

break more easily and are less hygienic. To over-come the hygiene problem, many orthodontists usethe acrylic splint Herbst appliance as a removablebite jumping device. However, the major advantageof the Herbst method, as a fixed functional appli-ance, working 24 hours a day, independent ofpatient cooperation, is lost with this adaptation.

a b

c d

e f

Fig 1 The banded Herbst appliance with simple (a) maxillary and (b) mandibular anchorage. Thebanded Herbst appliance with extended (c) maxillary and (d) mandibular anchorage. The cast splintHerbst appliance with all (e) maxillary and (f) mandibular teeth incorporated into anchorage.




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VOLUME 1, NUMBER 1, 2000 Pancherz/Ruf

TREATREATMENT POSSIBILITIESTMENT POSSIBILITIES

In current dentofacial orthopedics, Herbst appliancetherapy, followed by a conventional multibracketappliance treatment phase, is a most efficient 2-step approach in the management of severe Class IImalocclusions. In the first step, Class II correction isaccomplished with the Herbst appliance (6 to 8months of therapy). Final tooth alignment, in the sec-ond step, is performed with conventional multi-bracket appliances (8 to 12 months of treatment).

When the appliance is placed at the start of Herbsttreatment, the mandible is usually advanced to an

incisal edge-to-edge position and the condyles arepositioned on the top of the articular eminence. Dur-ing the course of therapy, however, the condyles returnto their original fossa position. This is accomplished byadaptive dental and skeletal changes: posterior move-ment of the maxillary dentition and anterior movementof the mandibular dentition,1 stimulation of sagittalcondylar growth in a more favorable direction,2,3 andremodeling of the glenoid fossa.3 Throughout treat-ment, a normal disc-to-condyle relationship is main-tained (Fig 2). At the end of treatment, the disc haseither returned to its original pretreatment position orhas attained a slightly retrusive position.4

Fig 2 Female Class II, Division 1subject, 16 years of age, treatedwith the cast splint Herbst appli-ance. Parasagittal MRIs of the rightTMJ exhibiting a physiologic disc-to-condyle relationship during dif-ferent phases of therapy. (a)Before treatment. (b) Start of treat-ment when the Herbst appliancewas placed. (c) After 12 weeks oftreatment. (d) After 7 months oftreatment when the appliance wasremoved. (e) One year posttreat-ment. Tracings of the articularstructures (condyle, disc, fossa) aregiven for better orientation.

a

d

cb

e




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Fig 3 Female Class II, Division 1 subject, 13 years of age, treated with a cast splint Herbst/multibracket appliance systemin combination with a rapid maxillary expander. (a) Before treatment. (b) Start of treatment when the cast splints (withoutthe telescope mechanism) were placed. (c) After 2 weeks of rapid maxillary expansion (when the telescope mechanismwas placed). Note the diastema and the open bite. (d) After 6 months of Herbst treatment, before the appliance wasremoved. (e) During the second phase of treatment with a multibracket appliance. (f) After 18 months of Herbst/multi-bracket appliance treatment. (g) Retention with a maxillary Hawley plate and a mandibular canine-to-canine retainer. (h)

Lateral head films from before treatment (left), after the Herbst treatment phase (middle), and after the multibracket treat-ment phase (right).

a

b

c

d

e

f

g




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The Herbst/multibracket appliance approachmakes it possible to treat severe Class II malocclu-sions, which otherwise would have been very diffi-cult, if not impossible, to handle without extractionor orthognathic surgery. Our clinical-experimentalresearch throughout the years has shown that theHerbst appliance is most useful in the Class II sub-jects and situations described below.

Class II, Division 1 malocclusions

This malocclusion is the main indication for Herbsttherapy. In cases with a narrow maxilla, it is advanta-geous to combine the maxillary splints with a rapidmaxillary expander (Fig 3) or a quad-helix.

In analyzing the treatment effects in consecu-tively treated subjects, it has been demonstratedthat Class II correction is the result of both skeletaland dental changes.5 Skeletal changes are morepronounced in early adolescent subjects, and dentalchanges are more pronounced in late adolescent oryoung adult patients6–9 (Fig 4).

In most Class II, Division 1 cases, an undesirableside effect of the Herbst appliance is the proclina-tion of the mandibular incisors. This effect is theresult of anchorage loss, due to the forces exertedby the telescope mechanism on the anterior teeth.The incisor proclination is difficult to control10 inde-pendently of the anchorage system used. However,no increased incidence of mandibular anteriorcrowding could be found several years posttreat-ment10,11 despite a spontaneous uprighting of theteeth after Herbst therapy.

Class II, Division 2 malocclusions

The Herbst appliance is also very effective in ClassII, Division 2 cases12 (Fig 5). In this type of malocclu-

sion, the mandibular incisors (as well as the maxil-lary incisors) have a retroclined position. Therefore,the mandibular anchorage loss (proclination of themandibular anterior teeth) during Herbst treatmentcan be used advantageously to reduce the interin-cisal angle and to create a stable anterior occlusion.This would be a prerequisite for the prevention of adeep bite relapse (Fig 5).

Furthermore, the changes in incisor tooth angula-tions during Herbst therapy will improve the verticallower lip to maxillary incisor relationship (Fig 5). A highlip line (the lower lip covering the maxillary incisors) is acommon finding in Class II, Division 2 malocclusionsand is considered to be both an etiologic and a relapsefactor for a deep bite. Therefore, the improvement in lipposition will favor the stability of the corrected overbite

High-angle malocclusions

Class II malocclusions with a hyperdivergent jaw baserelationship are generally considered to have an unfa-vorable growth pattern, making their treatment diffi-cult. As the Herbst appliance has been shown toincrease condylar growth in the therapeuticallydesired sagittal direction13 (Fig 6) without resulting ina posterior (backward) rotation of the mandible,14

high-angle Class II subjects are good candidates forsuccessful Herbst therapy (Figs 7 and 8).

Maxillary anterior crowding

Besides the orthopedic effect on the mandible, theHerbst appliance has a pronounced high-pull head-gear effect on the maxillary molars.15 During therapy,the molars are distalized and significantly intruded.The headgear effect is most useful in gaining ante-rior space and relieving crowding in the maxillarycanine and incisor areas (see web appendix Fig A-1).

h

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Fig 4 Maxillary and mandibular skeletal and dental changes contributing to overjet (left) and sagittal molar (right) correc-tion in (a) 25 early adolescent, (b) 21 late adolescent, and (c) 14 young adult subjects treated with the banded and the castsplint Herbst appliances for a period of 6 to 9 months.6,8 Negative (–) values indicate changes counteracting overjet andmolar correction.

Early adolescent treatment(n = 25)

Overjet correction9.8 mm100%

Dental6.0 mm

61%

Skeletal3.8 mm

39%

Maxilla-0.5 mm

-5%

Maxilla3.3 mm

34%

Mandible4.3 mm

44%

Mandible2.7 mm

27%

Late adolescent treatment(n = 21)

Molar correction6.1 mm100%

Dental3.8 mm

62%

Skeletal2.3 mm

38%

Maxilla-0.1 mm

-1%

Maxilla2.0 mm

33%

Mandible2.4 mm

39%

Mandible1.8 mm

29%

Early adolescent treatment(n = 25)


Dental5.5 mm

59%

Skeletal3.8 mm

41%

Maxilla-0.5 mm

-5%

Maxilla3.0 mm

32%

Mandible4.3 mm

46%

Mandible2.5 mm

27%

Late adolescent treatment(n = 21)


Dental6.1 mm

73%

Skeletal2.3 mm

27%

Maxilla-0.1 mm

-1%

Maxilla2.6 mm

31%

Mandible2.4 mm

28%

Mandible3.5 mm

42%

Young adult treatment(n = 14)


Dental7.4 mm

78%

Skeletal2.1 mm

22%

Maxilla-0.2 mm

-2%

Maxilla3.6 mm

38%

Mandible2.3 mm

24%

Mandible3.8 mm

40%

Young adult treatment(n = 14)


Dental6.5 mm

76%

Skeletal2.1 mm

24%

Maxilla-0.2 mm

-2%

Maxilla2.7 mm

32%

Mandible2.3 mm

26%

Mandible3.8 mm

44%

a

b

c

Fig 5 (Facing page) Male Class II, Division 2 subject, 14.5 years of age, treated with a cast splint Herbst/multibracketappliance system. (a) Before treatment. Note the high lip line (the lower lip covering the maxillary incisors). (b) Proclinationof the maxillary incisors. (c) During Herbst treatment. Note 2 mandibular advancement shims added to the plunger forreactivation of the telescope mechanism. (d) After 7 months of Herbst treatment, when the appliance was removed. Notethe Class I dental arch overcorrection, the lateral open bite, and the improvement of the lower lip to maxillary incisor rela-tionship. (e) During the multibracket phase of treatment. (f) After 2.4 years of Herbst/multibracket appliance treatment.Note the stability of the lower lip to maxillary incisor relationship.




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a

b

c

d

f

e




24


"High angle" treatment(n = 16)


Dental4.8 mm

63%

Skeletal2.8 mm

37%

Maxilla-0.2 mm

-2%

Maxilla1.8 mm

24%

Mandible3.0 mm

39%

Mandible3.0 mm

39%

"Low angle" treatment(n = 15)


Dental4.3 mm

75%

Skeletal1.4 mm

25%

Maxilla-0.5 mm

-9%

Maxilla2.4 mm

42%

Mandible1.9 mm

34%

Mandible1.9 mm

33%

"High angle" treatment(n = 16)


Dental3.6 mm

56%

Skeletal2.8 mm

44%

Maxilla-0.2 mm

-3%

Maxilla1.5 mm

23%

Mandible3.0 mm

47%

Mandible2.1 mm

33%

"Low angle" treatment(n = 15)


Dental4.1 mm

75%

Skeletal1.4 mm

25%

Maxilla-0.5 mm

-9%

Maxilla1.9 mm

35%

Mandible1.9 mm

34%

Mandible2.2 mm

40%

a

b

Fig 6 Maxillary and mandibular skeletal and dental changes contributing to overjet (left) and sagittal molar (right) correc-tion in (a) 16 high-angle and (b) 15 low-angle Class II, Division 1 malocclusions treated with the banded Herbst appliancefor a period of 6 to 8 months.12 Negative (–) values indicate changes counteracting overjet and molar correction.

Fig 7 (Facing page) Male high-angle Class II, Division 1 subject, 15 years of age, treated with a banded Herbst appliancein combination with a quad helix for maxillary expansion (not shown). (a) Before treatment. (b) During Herbst treatment.Note mandibular advancement shims added to the plunger. (c) After 6 months of Herbst treatment when the appliancewas removed. Note the Class I overcorrection and the open bite. (d) At 6 months posttreatment. Note the spontaneousclosure of the open bite. No multibracket or retention appliances were used after Herbst treatment.

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a

b

c

d

26





Fig 8 Male high-angle Class II, Division 1 subject, 14 years of age, treated with a banded Herbst/multibracket appliancesystem in combination with extraction of the 4 first premolars. (a) Before treatment. (b) Start of Herbst treatment whenthe appliance was placed. (c) After 6.5 months of Herbst treatment when the appliance was removed. (d) After 12 monthsof multibracket appliance treatment and extraction of the 4 first premolars. (e) At 12 months posttreatment.

a

b

c

d

e

Retrognathic facial profile

The excessive facial profile convexity characteristic ofClass II malocclusions is generally reduced by Herbsttherapy.16 This effect is obvious both in subjectstreated during growth and those treated at the end ofgrowth (“late” treatment, described below). The mostfavorable soft tissue profile changes are seen inClass II malocclusions with a retrognathic chin,retruded lower lip, and protruded upper lip (Fig 9).

Postpubertal/Young adult patients

Herbst therapy has been shown to be very succcess-ful not only in adolescent patients, but also in posta-dolescent and young adult patients.7–9 Althoughmandibular growth is almost completed in theseolder patients, our recent magnetic resonance imag-ing (MRI) studies have shown8 that some condylargrowth can be reactivated in subjects at the end ofgrowth (Fig 10).

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Fig 9 Male Class II, Division 1 sub-ject, 13 years of age, treated withthe Herbst appliance for 6 months.The boy has the prerequisites forfavorable profile treatment changes:retrognathic chin, retrusive lower andprotrusive upper lips. (Left) Beforetreatment. (Right) After treatment.

Fig 10 Female Class II, Division 1 subject, 19 years of age, treated with the cast splint Herbst/multibracket appliance sys-tem. Parasagittal MRIs of the right TMJ are shown. (a) Before treatment. (b) After 9 weeks of treatment. Note theremodeling of the condyle and ramus. (c) After 8 months of Herbst treatment, when the appliance was removed. Notethat the signs of remodeling have subsided.

a cb

Furthermore, in comparison to an “early” treat-ment approach (early adolescence/mixed dentition),“late” treatment (late adolescence/permanent den-tition) can more easily accomplish a stable post-treatment cuspal interdigitation, preventing arelapse.17,18 Additionally, the retention time can bereduced since the residual growth period (with apossible unfavorable growth pattern) is relativelyshort (Fig 11).

In our opinion, after extensive clinical experi-ences, early Class II treatment should be per-formed with removable functional appliances (notthe Herbst appliance) because these appliancesare more effective and easier to handle in youngchildren. Herbst treatment, on the other hand,should be confined to patients who are in thepubertal-postpubertal growth period and have theirpermanent dentition; at these late somatic anddental developmental stages, removable appli-ances are less efficient and patient compliance ismore difficult.

Alternative to orthognathic surgery

As mentioned above, our recent clinical, cephalo-metric roentgenographic, and MRI research hasshown that the Herbst appliance is very efficient inClass II subjects at the end of their growth (radiusunion).8,9 Thus, we consider the method to be analternative to orthognathic surgery in many adultClass II subjects (Figs 12 and 13). Our conviction issubstantiated by the findings from an ongoing studythat compares young Class II adults treated witheither the Herbst appliance or with mandibularsagittal split osteotomy. Comparable changes insagittal maxillary/mandibular jaw base relationshipand skeletal profile convexity were seen in the 2

groups at the end of treatment (after final toothalignment with multibracket appliances) (Fig 14).Furthermore, in comparison to surgery, Herbst treat-ment implies lower costs and lower risks for thepatient without increasing total treatment time.

TMJ patients

Our short- and long-term TMJ research using tomog-raphy19 and MRI4,20 has shown no adverse effectsof Herbst treatment on the different hard and softtissue joint structures. However, many cases havedemonstrated that Herbst therapy results in a retru-sion of the articular disc.4 This effect can be used inthe therapy of Class II malocclusions with milderforms of anterior disc displacement to attain areduction of the disc malposition (Fig 15).

NEW CONCEPT OF NEW CONCEPT OF CLASS II THERAPYCLASS II THERAPY

With respect to age and growth development, thedominant current concept of Class II treatment is:

• Growth adaptation in children and adolescents• Camouflage orthodontics in postadolescents• Surgical correction in adults

However, when considering the fact that skeleto-facial growth continues many years after cessationof body height growth and that the adult TMJ iscapable of remodeling,8,9,21,22 it seems logical torevise the above treatment concept. Thus, withrespect to age and growth development, the follow-ing modified new concept for Class II therapy isproposed:

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100

80

60

40

20

0

%

Early n = 31 Late n = 24

Overjet Molarrelation

Overjet Molarrelation

Relapse

Stable

Fig 11 Diagram exhibiting the long-term results of Herbsttreatment with respect to stability and relapse in overjetand sagittal molar relationship. Evaluation of patients 5 to10 years posttreatment. Thirty-one subjects were treated“early” (early adolescence/ mixed dentition) and 24 sub-jects were treated “late” (late adolescence/permanentdentition).17

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a

b

c

Fig 12 Adult female Class II, Division 1 subject, 18 years of age, treated with the cast splint Herbst/multibracket appli-ance system. (a) Before treatment. (b) Start of Herbst treatment when the appliance was placed. (c) After completion ofHerbst/multibracket appliance treatment. Note the improvement in the hard and soft tissue profile. Total treatment timewas 24 months.

a

b

c

Fig 13 Adult female Class II, Division 1 subject, 34 years of age, treated with the cast Herbst/multibracket appliance sys-tem. (a) Before treatment. (b) During the Herbst phase of treatment. (c) After completion of Herbst/multibracket appliancetreatment. Note the improvement in the hard and soft tissue profile seen in the cephalogram. Total treatment time was 15months.

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c

0

+5

+4

+3

+2

+1

-1

-2

-3

-4

-5

Herbst n = 12

Surgery n = 16

Deg

rees

Wits

Young adults / Class II:1

Skeletal profile anglemm

Fig 14 Sagittal inter-jaw base relationship (Witsappraisal) and skeletal profile convexity (N-A-Pg). Changesin young adults treated with either the cast splint Herbstappliance (n = 12) or with mandibular sagittal split osteo-tomy (n = 16).

Fig 15 Male Class II, Division 1 subject, 12 years of age, with an anterior discdisplacement with reduction. Treatment with the cast splint Herbst appliance.Analyses of parasagittal TMJ-MRIs. (a) Before treatment. Note the anterior discdisplacement. (b) Start of treatment when the Herbst appliance was placed.Note the disc reduction accomplished when the condyle was placed on thearticular eminence. (c) After 12 weeks of treatment. Note the return of thecondyle to its original fossa position and the physiologic disc-to-condyle relation-ship. (d) After 7 months of Herbst treatment when the appliance was removed.Note the stability of the normal disc-to-condyle relationship.18

a b

d




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• Growth adaptation in children, adolescents,postadolescents, and young adults

• Camouflage orthodontics in older adults• Surgical correction in older adults

Growth adaptation

Growth adaptation should be performed with remov-able functional appliances in children and adoles-cents with mixed dentition. However, in adolescentswho have their permanent dentition, in postadoles-cents, and in young adults, the Herbst appliance isusually indicated. The approximate age for youngadulthood would be 18 to 24 years in females and20 to 25 years in males. An upper age limit for suc-cessful Herbst treatment is, however, difficult todefine (Fig 15).

Camouflage orthodontics

Camouflage orthodontics mainly comprises toothsacrifice in the maxillary dental arch to create spacefor retraction of the anterior teeth. By this approach,however, the skeletal Class II problem (mandibularretrusion) remains.

Surgical correction

Surgical correction implies that the mandible isadvanced to a Class I skeletal jaw relationship usingeither sagittal split osteotomy or mandibular distrac-t ion osteogenesis. Occasionally, mandibularadvancement is combined with maxillary setbacksurgery (Le Fort I). The philosphical question isbased on potential iatrogenic sequelae for a primar-ily cosmetic problem: “What price surgery?”

REFERENCESREFERENCES

1. Pancherz H, Hansen K. Occlusal changes during and afterHerbst treatment: A cephalometric investigation. Eur JOrthod 1986;8:215–228.

2. Pancherz H, Littmann C. Morphologie und lage des unter-kiefers bei der Herbst-behandlung. Eine kephalometrischeanalyse der veränderungen bis zum wachstumsabschluss.Inf Orthod Kieferorthop 1989;21:493–513.

3. Ruf S, Pancherz H. Temporomandibular joint growth adapta-tion in Herbst treatment: A prospective magnetic resonanceimaging and cephalometric roentgenographic study. Eur JOrthod 1998;20:375–388.

4. Pancherz H, Ruf S, Thomalske-Faubert C. Mandibular articu-lar disc position changes during Herbst treatment: A prospec-tive longitudinal MRI study. Am J Orthod Dentofacial Orthop1999;116:207–214.

5. Pancherz H. The mechanism of Class II correction in Herbstappliance treatment. A cephalometric investigation. Am JOrthod 1982;82:104–113

6. Pancherz H, Hägg U. Dentofacial orthopedics in relation tosomatic maturation. An analysis of 70 consecutive casestreated with the Herbst appliance. Am J Orthod1985;88:273–287.

7. Konik M, Pancherz H, Hansen K. The mechanism of Class IIcorrection in late Herbst treatment. Am J Orthod DentofacialOrthop 1997;112:87–91.

8. Ruf S, Pancherz H. Temporomandibular joint remodeling inadolescents and young adults during Herbst treatment: Aprospective longitudinal magnetic resonance imaging andcephalometric radiographic investigation. Am J Orthod Dento-facial Orthop 1999;115:607–618.

9. Ruf S, Pancherz H. Dentoskeletal effects and facial profilechanges in young adults treated with the Herbst appliance.Angle Orthod 1999;69:239–246.

10. Pancherz H, Hansen K. Mandibular anchorage in Herbsttreatment. Eur J Orthod 1988;10:149–164.

11. Hansen K, Koutsonas T, Pancherz H. Long-term effects ofHerbst treatment on the mandibular incisor segment: Acephalometric and biometric investigation. Am J OrthodDentofacial Orthop 1997;112:92–103.

12. Obijou C, Pancherz H. Herbst appliance treatment of Class II,Division 2 malocclusions. Am J Orthod Dentofacial Orthop1997;112:287–291.

13. Ruf S, Pancherz H. The mechanism of Class II correction dur-ing Herbst therapy in relation to the vertical jaw base rela-tionship: A cephalometric roentgenographic study. AngleOrthod 1997;67:271–276.

14. Ruf S, Pancherz H. The effect of the Herbst appliance on themandibular plane angle. A cephalometric roentgenographicstudy. Am J Orthod Dentofacial Orthop 1996;110:225–230.

15. Pancherz H, Anehus-Pancherz M. The head-gear effect of theHerbst appliance. A cephalometric long-term study. Am JOrthod Dentofacial Orthop 1993;103:510–520.

16. Pancherz H, Anehus-Pancherz M. Facial profile changes dur-ing and after Herbst appliance treatment. Eur J Orthod1994;16:275–286.

17. Pancherz H. The nature of Class II relapse after Herbst appli-ance treatment. A cephalometric long-term investigation. AmJ Orthod Dentofacial Orthop 1991;100:220–233.

18. Pancherz H. Früh- oder spätbehandlung mit der Herbst-Appa-ratur—stabilität oder rezidiv? Inf Orthod Kieferorthop 1994;26:437–445.

19. Hansen K, Pancherz H, Petersson A. Long-term effects of theHerbst appliance on the craniomandibular system with spe-cial reference to the TMJ. Eur J Orthod 1990;12:244–253.

20. Ruf S, Pancherz H. Long-term TMJ effects of Herbst treat-ment: A clinical and MRI study. Am J Orthod DentofacialOrthop 1998;114:475–483.

21. Woodside DG, Altuna G, Harvold E, Herbert M, Metaxas A.Primate experiments in malocclusion and bone induction.Am J Orthod 1983;83:460–468.

22. McNamara JA Jr, Hinton RJ, Hoffman DL. Histological analy-sis of temporomandibular joint adaptation to protrusive func-tion in young adult rhesus monkey (Macaca mulatta). Am JOrthod 1982;82:288–298.




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Fig A-1 Female Class II, Division 1 subject, 15 years of age, with almost complete space closure, after traumatic loss ofthe left permanent maxillary central incisor at the age of 10 years. Treatment with the cast splint Herbst/multibracket appli-ance system in combination with a rapid maxillary expander. (a) Before treatment. (b) Start of treatment with the Herbstappliance and the maxillary expander were placed. (c) During Herbst treatment. Note the transverse maxillary expansionand the spaces that developed distally to the maxillary canines as a result of the headgear effect of the Herbst appliancemoving the lateral teeth posteriorly. (d) After 12 months of Herbst treatment, when the appliance was removed. Note theovercorrected Class I dental arch relationships and the space opening for the left central incisor. (e) During the multi-bracket phase of therapy. Note the maxillary plate replacing the missing central incisor. (f) After 6 months of multibracketappliance treatment. Note the complete space opening for the central incisor, and the correction of the midline and theClass I dental arch relationships. After completion of growth, an incisor implant in planned.

a

b

c

d

e

f

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the herbst appliance: research- based updated clinical...

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