European Journal of Orthodontics 30 (2008) 120–127
Advance Access publication 23 January 2008
© The Author 2008. Published by Oxford University Press on behalf of the European Orthodontic Society.
All rights reserved. For permissions, please email: email@example.com.
The effi cacy of the Herbst appliance in normalizing the
sagittal dental arch relationship in patients with a Class II
division I malocclusion is well documented. The correction
is partly achieved by anterior mandibular tooth movement
and incisor proclination, as well as by posterior movement
of the maxillary teeth. The use of the Herbst appliance also
results in increased mandibular condylar growth ( Pancherz,
1979 , 1982 ; Paulsen, 1997 ; Paulsen et al. , 1998 ; Manfredi
et al. , 2001 ) and glenoid fossa remodelling ( Woodside et al. ,
1987 ; Ruf and Pancherz, 1999 ; Voudouris et al. , 2003a , b ).
The Herbst appliance was fi rst introduced in 1905 ( Herbst,
1934 ). Schwarz (1934) presented a number of improvements
of the dental anchor age system. After a period of virtual
oblivion, the Herbst appliance was re-introduced by Pancherz
(1979) . Since then, several modifi cations of the original
design have appeared. Examples of this are the bonded
Herbst appliance with upper and lower acrylic splints ( Howe,
1982 ), the cast splint Herbst appliance in combination with
headgear ( Wieslander, 1984 ), the Herbst appliance with a
mandibular acrylic splint and stainless steel crowns on the
maxillary fi rst molars ( Valant and Sinclair, 1989 ), and cast
splints equipped with a Herbst mechanism with ball and
socket hinges (Herbst IV®).
The integrated Herbst appliance — treatment effects in a group
of adolescent males with Class II malocclusions compared with
growth changes in an untreated control group
Paul Hägglund *, *** , Staffan Segerdal **, *** and Carl-Magnus Forsberg ****
* Department of Orthodontics, University of Umeå , ** Clinic of Orthodontics, Sundsvall , *** Department of Research
and Development Västernorrland County Council and **** Karolinska Institutet, Huddinge, Sweden
SUMMARY In this study, the effect of the integrated Herbst appliance (IHA) was examined in 30 Swedish
males (mean age 14.2 ± 0.96 years) with a Class II malocclusion. An evaluation of hand – wrist radiographs
showed that the patients were in the maturation stages MP3-F, MP3-FG, or MP3-G at the start of
treatment. The average treatment time with the Herbst mechanics was 0.7 years. Dentoskeletal and soft
tissue parameters were analysed on lateral radiographic head fi lms taken at the start and end of the IHA
treatment. The pre- and post- H erbst values of a number of skeletal and dental variables in the treatment
group were compared with the corresponding values in a group of untreated age-matched males with
Class II malocclusions. Differences in the cephalometric measurements pre- and post-Herbst treatment
were determined using paired t -tests.
In general, the control group exhibited only minor or no changes during the period of observation,
whereas treatment with the IHA resulted in statistically signifi cant and favourable changes of the
recorded variables. In the IHA patients, ANB angle was reduced on average by 2.1 degrees. However, a
skeletal post-normality (ANB = 3.9 degrees) remained even though a Class I dental relationship had been
obtained. In comparison with treatment effects achieved with other designs of Herbst appliances, some
minor differences in the changes of the variables SNA and ML/NSL were noted in the present study.
These differences could probably be attributed to the particular treatment protocol which was applied in
the IHA treatments.
The design of the Herbst appliance used in the present
study has been previously described in detail ( Haegglund
and Segerdal, 1997 ). The development of this appliance
was started in 1986 when the authors focused on fi nding a
simple way of integrating the Herbst mechanism with a
standard upper and lower fi xed appliance. With such an
arrangement, the complete fabrication of the Herbst
appliance could be performed in the clinic without
involvement of a dental technician. Furthermore, possible
problems with the appliance during treatment could be
immediately and easily solved in the clinic, making
involvement of a dental laboratory unnecessary.
The aim of the present investigation was to study the
treatment effects of this modifi ed Herbst appliance on a
number of dentofacial variables and compare the skeletal,
dental, and soft tissue profi le changes with the corresponding
morphological changes of an untreated group of subjects
with a post-normal occlusion.
Materials and methods
The records of 174 patients who had undergone treatment
with the integrated Herbst appliance (IHA) at the Clinic of
Orthodontics in Sundsvall, Sweden, were analysed as a part
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THE INTEGRATED HERBST APPLIANCE —TREATMENT EFFECTS
of a treatment quality project. The following radiographic
records were available for each patient:
1. Standardized lateral cephalometric radiographs at the
start and termination of Herbst treatment.
2. Hand-wrist radiographs taken at the time of insertion of
the Herbst appliance.
From these patients, a consecutive group of Caucasian
boys who fulfi lled the criteria listed below was selected for
the present investigation.
1. No extractions of the permanent teeth either before or
during Herbst treatment.
2. The skeletal maturation phase at the start of Herbst
treatment should be MP3-F, MP3-FG, or MP3-G (from
onset of the pubertal growth spurt to peak) as evaluated
on the hand-wrist radiographs ( Hägg and Taranger, 1980 ,
1982 ). Two investigators (PH and SS) evaluated the
radiographs. Any disparities in the assessment of skeletal
maturation were discussed until consensus was reached.
3. ANB angle ≥ 4 degrees and overjet ≥ 6 mm after levelling
of the teeth with fi xed appliance.
Thirty-one boys fulfi lled these criteria. However, one boy
exhibited a considerable delay in skeletal maturation as a
consequence of which his chronological age at the start of
treatment was comparatively high. Since the control records
did not cover such high age levels, this subject was excluded
from the study.
The dental maturity of the patients corresponded to the
dental stages DS4/M1 ( n = 2) or DS4/M2 ( n = 28).
All patients had at least an end-to-end Class II molar
relationship before treatment. In three of the 30 patients, the
malocclusions were diagnosed as Class II division 2. During
the alignment phase, i.e. before insertion of the IHA, these
dentitions were changed to a Class II occlusion with
normally inclined or slightly proclined upper incisors.
Ten of the patients had previously undergone activator
treatment with poor results due to lack of compliance.
The Herbst treatments had been carried out by three
orthodontists using basically the same technique. At the
start of treatment, the mean age of the subjects was 14.2 ±
0.96 years (range 12.5 – 16.2 years). At this stage, three
patients were in maturation phase MP3-F, three in MP3-FG,
and 24 in MP3-G. The average treatment time with the IHA
was 8 months and 13 days (0.70 years, range 0.5 – 0.9 years).
Consequently, the mean post- H erbst age was 14.9 ± 0.95
years (range 13.2 – 16.8 years).
Before insertion of the IHA, the dental arches were
levelled with upper and lower fi xed appliances, which
included bands with headgear tubes on the upper fi rst molars
and bands with a rectangular and a round tube (0.036 – 0.045
inch) on the lower fi rst molars. The inclination of the upper
and lower anterior teeth was also adjusted, and the incisors
were intruded when necessary. After this initial treatment
procedure, which took on average 9.3 months, heavy
rectangular stainless steel arch wires in the upper and lower
jaw and the Herbst appliance could be inserted ( Haegglund
and Segerdal, 1997 , Figure 1 ). Apart from some minor
improvements of the connection between the Herbst
components and the fi xed appliance, no changes to the
appliances were carried out during the period of
The control subjects, who were of Austrian origin, were
selected from the cross-sectional roentgen cephalometric
material of orthodontically untreated children and
adolescents presented by Droschl (1984) . The diagnosis of
a Class II malocclusion was applied when there was a Class
II relationship exceeding one-quarter premolar width,
increased overjet, and incisor protrusion. In the age interval,
which corresponds to the pre- H erbst age range of the
treatment group (12.5 – 16.2 years), this material comprised
64 males with post-normal occlusion. Seventeen of these
subjects had to be excluded due to the fact that they exhibited
an ANB angle and/or an overjet smaller than 4 degrees and
6 mm, respectively. After this reduction, the control group
for pre- H erbst comparisons comprised 47 subjects. The
control group for the post- H erbst comparisons was selected
in a similar way, and 33 control subjects were available in
the age range 13.2 – 16.8 years.
According to the Greulich and Pyle (1959) method, the
skeletal age of the controls was estimated to be retarded, 4.6
months on average, in relation to chronological age.
However, when this assessment was performed on the same
material using the method of Tanner and Whitehouse
( Wenzel et al. , 1984 ), a closer agreement between skeletal
and chronological age was found. These results suggest that
the majority of the control subjects could be expected to be
in the maturation stages MP3-F, MP3-FG, or MP3-G ( Hägg
and Taranger, 1980 , 1982 ; Hägg and Pancherz, 1988 ).
Figure 1 The integrated Herbst appliance. The Herbst pistons are
connected to an auxiliary arch wire (0.9 – 1.0 mm). This arch wire is inserted
in round tubes on the lower fi rst molar bands and anteriorly attached to the
main arch wire with elastomeric modules. The Herbst tubes are attached to
the headgear tubes on the upper fi rst molar bands with hooks made of
0.9 – 1.0 mm hard stainless steel wire.
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P. HÄGGLUND ET AL.
All radiographic registrations of the patients were made
with the same X -ray equipment and by the same operator.
The head fi lms were exposed with the patients standing
with the teeth in centric occlusion (intercuspal position:
ICP). The enlargement factor was 9.1 per cent. Corrections
for linear magnifi cation were not made.
A matte acetate tracing fi lm was placed on the lateral
head fi lm and relevant reference points ( Figure 2 ) and lines
( Figure 3 ) were marked with a pencil (0.3 mm 2H). All
tracings were digitized with a Scriptel RTD digitizer
(Scriptel Corporation, Toronto, Canada), and measurements
of the angular and linear variables listed in Table 1 were
performed with an accuracy of 0.1 mm or 0.1 degree using
the Dentofacial Planner computer program (Dentofacial
Planner Software Inc., Toronto, Canada).
The evaluation of treatment changes was carried out by
comparing the pre- and post-treatment tracings. This
procedure was based on superimposition of the tracings on
stable cranial base structures according to the technique
described by Björk and Skieller (1983) .
The corresponding individual measurements in the
control material were obtained directly from the author
( Droschl, 1984 ). The magnifi cation factor of the
cephalometric data of the control material was not
known. However, in order to be able to compare linear
measurements in patients and controls, it was necessary to
establish the magnifi cation factor in the control group. A
conceivable way of obtaining an acceptable estimation of
the magnifi cation factor would be to calculate it on the
basis of the length of the cranial base. Craniometric studies
of Caucasian, African, and Asian skulls of different ethnic
origins and shapes have shown that the variability of
Figure 2 Reference points used in the cephalometric analysis. The
defi nitions of the reference points are those given by Droschl (1984) .
Figure 3 Reference lines used in the cephalometric analysis. Defi nitions
of ML, NL, NSL, OL, RL, and Ils lines are those given by Björk (1960) .
The Apg and E-lines have been defi ned according to Ricketts (1957)
Table 1 The intercept values of the variables recorded in the
patients and controls at 14.2 years of age (pre-Herbst). The level of
statistical signifi cance of differences between the groups was
calculated with t -test.
n = 30
n = 47
* P < 0.05, ** P < 0.01, *** P < 0.001.
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THE INTEGRATED HERBST APPLIANCE —TREATMENT EFFECTS
cranial base length is small ( Martin and Saller, 1959 , Kuroe
et al. , 2004 ). Roentgen cephalometric studies of the length
of the anterior cranial base of individuals with different
ethnic backgrounds have also shown that the mean values
and standard deviations are comparable in the different
groups ( Solow and Sarnäs, 1982 ; Kerr and Ford, 1986 ,
Dibbets and Nolte 2002 ). To the best of our knowledge, a
comparison of anterior cranial base length between
Swedish and Austrian subjects has not been carried out.
However, there is no reason to believe that such a
comparison would produce a result which differs from
those of previous studies in this fi eld. When not corrected
for radiographic enlargement, the anterior cranial base
length at the start of Herbst treatment was on average 75.3
mm in the patient group. The corresponding measurement
in the control group was on average 75.0 mm. Post-Herbst
these distances were 76.9 and 76.5 mm, respectively,
in the treated and control groups. On the basis of these
observations, it was considered reasonable to assume that
the magnifi cation factors which apply to the two groups
were nearly identical.
Two-thirds of the patient cephalograms had been analysed
by one author (PH) and one-third by another author (SS)
Before the start of the tracing procedure, a calibration was
performed between the examiners as regards the identifi cation
of the landmarks. The concordance in landmark identifi cation
was tested by double determinations of the relevant angular
and linear measurements of 10 randomly chosen head fi lms.
The interindividual method errors ( s i ) were then calculated
according to Dahlberg’s (1940) formula:
where ‘ d ’ is the difference between the fi rst and second
measurements and ‘ n ’ is the number of double determinations.
The method errors of the angular measurements were found
to vary between 0.2 (ANB) and 0.9 (RL/ML) degrees, with
the exception of the variable Ils/NSL which exhibited an
error of 1.7 degrees. The method error of the linear
measurements varied between 0.5 and 0.6 mm.
The infl uence of the method error on the cephalometrically
determined treatment changes was evaluated using the pre-
and post- H erbst head fi lms of 20 randomly selected patients.
Tracings and measurements of both the pre- and the post-
H erbst fi lms of each patient were performed on two
occasions with an interval of at least 3 months. The post-
H erbst tracings obtained on the fi rst occasion were
superimposed on their respective pre- H erbst tracings and
the sizes of the changes (changes A) which had occurred
during treatment could be determined. Subsequently, the
corresponding changes (changes B) were determined on the
basis of the second set of pre- and post- H erbst tracings.
Finally, the differences between changes A and B were
entered into Dahlberg’s (1940) formula (see above) and a
combined method error, which included errors in the
location of landmarks as well as superimposition and
measurement errors, could be calculated for each variable.
The method error for linear variables varied between 0.5
(ii-Apg, ii-npg, is-npg, overbite, Li-E-line) and 0.8 mm (s-
gn). The corresponding values for angular measurements
were 0.5 (SNB, ANB, snpg) and 1.4 degrees (Ils/NL).
In the control material, the method error according to
Dahlberg’s (1940) formula (based on double determinations
carried out on 12 cephalograms) varied between 0.3 (is-
npg) and 1.2 (overbite) mm for linear measurements and
between 0.7 (snpg) and 1.5 (ML/NL) degrees for angular
measurements ( Droschl, 1984 ).
Within the treatment and control groups, a regression line
of the pre-Herbst cephalometric measurements on age was
calculated for each variable: y = a + b × age + c × group.
The observations for each variable were plotted in
diagrams in order to check that the linear regression
actually gave a reasonable fi t. Through geometric
translation of the y -axis, the intercepts ( a ) and the standard
errors of the intercepts were calculated ( Draper and Smith,
1966 ) at the age of 14.2 years, which was the mean age at
the start of treatment. Comparisons of the estimated
intercepts ( a ) for patients and controls were then performed
with the independent t -test. Corresponding regression
lines were formed for the post-Herbst cephalometric
measurements, and comparisons were then made of the
calculated intercepts for patients and controls at 14.9
years, which was the mean age at the end of the treatment
with the Herbst mechanics.
Differences between the
cephalometric measurements in the patient group were
tested for signifi cance with a paired t -test.
pre- and post-Herbst
The cephalometric variables in the Herbst and control
groups before treatment are compared in Table 1 . With the
exception of RL/ML, which was 3.5 degrees larger in the
control group ( P < 0.05), there were no signifi cant differences
between the skeletal variables of the patient and control
groups. However, the linear variables which describe the
position of the incisors differed, on average, between 1.3
and 1.9 mm between the groups. These differences could
partly be explained by the fact that alignment of teeth, and
in some cases also intrusion of the incisors, had been carried
out in the patients before insertion of the IHA.
Table 2 shows the changes which occurred in the patients
during treatment with the IHA. With the exception of the
variables NL/NSL, RL/ML, and Li-E-line, all linear and
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P. HÄGGLUND ET AL.
angular measurements exhibited statistically signifi cant and
After an average treatment time of 8 months 13 days
(0.70 years) with the IHA, the ANB angle in the patient
group was signifi cantly smaller than that of the control
group ( P < 0.001; Table 3 ). In the vertical plane, the patients
exhibited a signifi cantly greater posterior face height (s-go)
than the controls ( P < 0.05) post- H erbst. As regards dental
measurements, there were six signifi cant differences
between the patients and controls. The distance between the
incisal edge of the upper incisors and the npg line was
reduced in the treatment group and was signifi cantly smaller
than in the controls ( P < 0.01). The incisal edge of the lower
incisors had been anteriorly displaced as a result of IHA
treatment and, in relation to the Apg line, this distance was
signifi cantly larger ( P < 0.05) in the patients as compared
with the controls.
The signifi cant changes in incisor positions in the patients
were also refl ected in the overjet value, which was normal
after treatment. In the control group, this value was 7.9 mm
and signifi cantly larger than in the treatment group ( P < 0.001).
The overbite had been reduced to 1.9 mm in the patients, while
no such change had occurred in the controls, and the mean
values in the two groups were signifi cantly different ( P <
Finally, normalization of the overjet in the patient group
resulted in an improved upper lip position in relation to
the E-line, and this variable value was signifi cantly smaller
in the patient group as compared with the controls
( P < 0.05).
The effects of 0.70 years of treatment with the IHA on
dental and skeletal variables in a group of male patients
with a post-normal malocclusion were evaluated in this
investigation. The study was performed on cephalograms
taken of clinical material which was well defi ned as regards
gender, skeletal maturation, diagnosis, and method of
treatment. It would have been desirable to have access to
control material of similar quality. However, for ethical
reasons it is no longer possible to perform longitudinal
roentgenologic registrations of untreated patients with
post-normal occlusion. As a compromise, therefore, it was
considered acceptable to use cross-sectional material
comprising age-matched untreated males with post-normal
occlusion ( Droschl, 1984 ) as a control group.
Information regarding the roentgenographic enlargement
was lacking for the control material. However, a comparison
of the average anterior cranial base length in the patient and
control groups showed that these values were nearly
identical. Studies have shown that cranial base length
exhibits very little variation between groups of different
ethnic origins ( Martin and Saller, 1959 ; Dibbets and Nolte,
2002 ; Kuroe et al. , 2004 ), and on this basis it is reasonable
to presuppose that the roentgenographic magnifi cation
factor was the same in the two materials.
Table 2 Mean changes ( d ¯ ) and standard deviations (SD) of the
cephalometric values after 0.7 years of treatment with the
integrated Herbst appliance in 30 boys.
* P < 0.05, *** P < 0.001.
Table 3 The intercept values of the variables recorded in the
patients and controls at 14.9 years of age (post-Herbst). The level
of statistical signifi cance of differences between the groups was
calculated with the t-test.
n = 30
n = 33
Levels of signifi cance: * P < 0.05, ** P < 0.01, *** P < 0.001.
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THE INTEGRATED HERBST APPLIANCE —TREATMENT EFFECTS
As regards incisor relationship, the subjects in the patient
group exhibited somewhat greater deviations from normal
cepahlometric standards than the controls. An exception
from this common pattern was the overbite, which was
more pronounced in the controls. The reason for this was
that in patients with overerupted incisors and/or a ‘ gummy
smile ’ , active intrusion of the upper incisors was carried out
before insertion of the IHA. Naturally, these tooth
movements caused a reduction in the size of the overbite.
The correction of the post-normal occlusion, overjet, and
overbite was achieved by a combination of skeletal and
dental treatment effects. SNB increased on average by 1.1
degrees, from 75.3 to 76.4 degrees. This increase could be
attributed entirely to the effect of the Herbst treatment, as
no such change was found in the control group. There was a
similar relationship between the changes of the snpg angles
in the two groups, i.e., a signifi cant increase was recorded in
the patients, whereas the controls did not show any change.
In other studies of the effects of Herbst treatment, the
reported changes in SNB vary between 0.2 and 1.9 degrees
( Pancherz, 1982 ; Valant and Sinclair , 1989 ; McNamara
et al. , 1990 ; Wong et al. , 1997 ; Manfredi et al. , 2001 ;
Schaefer et al. , 2004 ). In those investigations, the subjects
were both males and females and the patients have usually
been younger than those in the present study. Furthermore,
treatment times from 6 to 13 months have been used, and
the designs of the Herbst appliances have varied. It may not
be relevant, therefore, to make a direct comparison between
the present SNB changes and those of previous studies. It
can be stated, however, that the degree of anterior
displacement of the mandible which was achieved with the
IHA bears a resemblance to the corresponding effects
produced by Herbst appliances of other designs.
A further measurement which indicated that favourable
anterior repositioning of the mandible had taken place was the
distance s-gn, which increased by 3.8 mm in the treated group.
In the control group the corresponding change was 2.3 mm.
SNA was found to have been signifi cantly reduced. When
compared with corresponding data presented by other authors
( Pancherz, 1982 , Valant and Sinclair , 1989 ; Wong et al. ,
1997 ; Manfredi et al. , 2001 ), the reduction of SNA was twice
as great in the present study. This could very well be due to
differences in the design and effi cacy of the appliances used.
When treatment is carried out with the IHA, all teeth are
bonded and aligned, and a heavy rectangular wire is inserted
and bent distal of the molar tubes in the upper and lower
dental arches before correction of the post-normality with the
Herbst mechanism is commenced. The posteriorly directed
functional force transferred by the IHA to the upper teeth is
thus distributed over the whole dental arch. This force could
also be assumed to produce a lingual root torquing effect on
the incisors and, as a result of this, a possible remodelling of
the alveolar bone in the subspinale area and a concomitant
posterior displacement of point A. Consequently, the relatively
large reduction of SNA recorded for the patients in the present
study was probably the result of the combined effects of
restriction maxillary anterior growth and bone remodelling.
The fact that one of the force components, which was
generated by the IHA, gave a certain degree of torquing on
the upper incisors may also explain why the considerable
average reduction of overjet by 7.1 mm in the patients only
caused a moderate retroclination of these teeth.
Although Class I occlusions with normal overjet and
overbite were achieved through treatment with the IHA, it
is obvious that the treatment did not entirely correct the
skeletal post-normality. The mean values of the variables
SNB and snpg indicated that a retrognathic mandible still
existed, and the average post-treatment ANB angle was 3.9
degrees. This value exceeds the norm for orthodontically
untreated Swedish males of the relevant age and with a
Class I occlusion by approximately 1.5 degrees ( Thilander
et al. , 2005 ). In spite of this skeletal problem, normal
occlusions could be achieved through dental compensations
related to the upper incisors which were somewhat
retroclined and the lower incisors which were slightly more
anteriorly positioned than normal after treatment.
During adolescence, the mandible normally exhibits an
anterior growth rotation which is refl ected in a continuous
small decrease of ML/NSL ( Riolo et al. , 1974 ; Bhatia and
Leighton, 1993 ; Thilander et al. , 2005 ). This pattern of
development was also found in the untreated control group
in which this angle decreased from 30.7 to 30.5 degrees
during the period of the investigation. Most studies of the
effects of Herbst treatment have reported the occurrence of
a small posterior rotation of the mandible, i.e., the ML/NSL
angle has increased ( Pancherz, 1982 ; Wieslander, 1984 ;
Valant and Sinclair, 1989; Wong et al. , 1997 ; Du et al. ,
2002 ; Schaefer et al. , 2004 ). In contrast to this, a signifi cant
mean decrease of 0.4 degrees of ML/NSL was recorded in
the present study, a change which is comparable with that of
the normal pattern of mandibular growth rotation. Du et al.
(2002) reported a similar reduction of the mandibular plane
angle in patients who had been treated with a ‘ splinted ’
Herbst appliance in combination with high-pull headgear
and with a step-by-step advancement of the mandible.
One factor which may indirectly reduce the risk of posterior
rotation of the mandible during treatment with the IHA is the
intrusion of the incisors with fi xed appliances which is carried
out before insertion of the Herbst mechanics. This adjustment
of the curve of Spee makes it possible to jump the mandible
forward to an edge-to-edge incisor relationship with only a
small concomitant posterior rotation of the mandible and
opening of the bite in the lateral segments. Moreover, the
vertical vector of the functional force which is transferred by
the IHA to the teeth may have an intrusive effect on the
posterior segments of the maxillary dentition. This effect is
benefi cial and may also counteract the tendency of posterior
mandibular rotation which has been reported in previous
studies ( Pancherz, 1982 ; Wieslander, 1984 ; Valant et al. , 1989;
Wong et al. , 1997 ; Du et al. , 2002 ; Schaefer et al. , 2004 ).
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P. HÄGGLUND ET AL.
Anterior (n-me) and posterior (s-go) face heights
increased on average by 2.7 and 2.6 mm, respectively, in the
patient group. In the control group, n-me increased from
122.5 to 124.6 mm (2.1 mm) and s-go from 82.6 to 84.4 mm
(1.8 mm). These changes in vertical facial dimensions are
within normal limits in boys at this stage of dentofacial
With respect to dental changes, the IHA treatment resulted
in increased values of the variables ii-Apg and ii-npg and a
reduction of is-npg, that is, anterior repositioning of the lower
incisors and posterior repositioning of the upper incisors had
occurred. The overjet and overbite decreased signifi cantly by
7.1 mm and 2.2 mm, respectively, and after treatment both
these measurements were normal. In the control group, no
such favourable dental changes were recorded. On the contrary,
both overjet and overbite showed a tendency to increase during
the period of the investigation. In other studies of the effects of
Herbst treatment, the average overjet reductions have varied
between 5.1 and 10.4 mm ( Pancherz, 1982 ; Wong et al. , 1997 ;
Du et al. , 2002 ; Schaefer et al. , 2004 ).
Correction of the incisor relationship in the patient group
signifi cantly improved the position of the upper lip in
relation to the E-line, whereas the lower lip position showed
only a small and not signifi cant average change. In the
control group, no signifi cant changes of these variables were
recorded. The mean values for upper and lower lip position
in relation to the E-line in Swedish 15-year-old males with
normal occlusion are − 3 mm and − 2 mm, respectively
( Forsberg and Odenrick, 1979 ). Consequently, correction of
the post-normal malocclusion had lead to a nearly normal
upper lip position ( − 2.3 mm), whereas the lower lip still
exhibited moderate protrusion after treatment ( − 0.5 mm).
The treatment with the IHA described in this study was
followed by a fi nishing stage which took on average 5.9
months. Thus, the total mean treatment time including the
alignment, Herbst, and fi nishing stages was 23.9 months.
Bearing in mind the severity of the malocclusions, this
treatment time seems reasonable. Furthermore, the fact that
neither the fabrication nor the possible repair of the IHA
requires any involvement by a dental technician facilitates
the clinical work and reduces the risk for unnecessarily long
interruptions in treatment due to broken appliances.
Eight months of treatment with the IHA was carried out in a
group of boys in the MP3 stage of maturation. A Class I
dental arch relationship was achieved in all subjects. A
moderate skeletal post-normality still existed after treatment,
although the therapy resulted in a signifi cant increase of
SNB and a signifi cant decrease of SNA.
IHA therapy seemed to produce a somewhat greater
reduction in SNA than treatment with Herbst appliances of
other designs. Furthermore, the posterior mandibular
rotation, which is a common fi nding in connection with
Herbst appliance treatment, was not seen in the patients
treated with the IHA.
Address for correspondence
Kommendörsgatan 8 L
SE-114 48 Stockholm
The authors would like to express their gratitude to Professor
Helmut Droschl, Universitätsklinik Graz, Austria, for giving
us access to the cephalometric data from his study. We
would also like to thank Mr Bo Nilsson at the Unit of Cancer
Epidemiology, Karolinska Hospital, Stockholm, for helpful
advice and guidance in the statistical processing of the
Bhatia S N , Leighton B C 1993 A manual of facial growth: a computer
analysis of longitudinal cephalometric growth data. Oxford University
Press , Oxford
Björk A 1960 The relation of the jaws to the cranium. In: Lundström A
(ed.) Introduction to orthodontics . McGraw-Hill Book Company, Inc ,
New York , pp 109 – 110
Björk A , Skieller V 1983 Normal and abnormal growth of the mandible. A
synthesis of longitudinal cephalometric implant studies over a period of
25 years . European Journal of Orthodontics 5 : 1 – 46
Dahlberg G 1940 Statistical methods for medical and biological students.
Interscience Publications , New York , pp. 122 – 132 .
Dibbets J M H , Nolte K 2002 Comparison of linear cephalometric
dimensions in Americans of European descent (Ann Arbor, Cleveland,
Philadelphia) and Americans of African descent (Nashville) . Angle
Orthodontist 72 : 324 – 330
Draper N R , Smith H 1966 Applied regression analysis. John Wiley and
Sons Inc. , New York
Droschl H 1984 Die Fernröntgenwerte unbehandelter Kinder zwischen
dem 6. und 15. Lebensjahr. Quintessenz Verlags-GmbH , Berlin
Du X , Hägg U , Rabie A B M 2002 Effects of headgear Herbst and
mandibular step-by-step advancement versus conventional Herbst
appliance and maximal jumping of the mandible . European Journal of
Orthodontics 24 : 167 – 174
Forsberg C-M , Odenrick L 1979 Changes in the relationship between the
lips and the aesthetic line from eight years of age to adulthood . European
Journal of Orthodontics 1 : 265 – 270
Greulich W W , Pyle S I 1959 Radiographic atlas of skeletal development
of the hand and wrist, 2nd edn. Stanford University Press , Stanford
Haegglund P , Segerdal S 1997 The Swedish-style integrated Herbst
appliance . Journal of Clinical Orthodontics 31 : 378 – 390
Hägg U , Taranger J 1980 Skeletal stages of the hand and wrists as indicators
of the pubertal growth spurt . Acta Odontolgica Scandinavica 38 : 187 – 200
Hägg U , Taranger J 1982 Maturation indicators and the pubertal growth
spurt . American Journal of Orthodontics 82 : 299 – 309
Hägg U , Pancherz H 1988 Dentofacial orthopaedics in relation to
chronological age, growth period and skeletal development. An analysis
of 72 male patients with Class II division 1 malocclusion treated with
the Herbst appliance . European Journal of Orthodontics 10 : 169 – 176
by guest on June 2, 2013
THE INTEGRATED HERBST APPLIANCE —TREATMENT EFFECTS
Herbst E 1934 Dreissigjährige Erfahrungen mit dem Retentions-Scharnier .
Zahnärztliche Rundschau 43 : 1515 – 1524, 1563 – 1568, 1611 – 1616
Howe R P 1982 The bonded Herbst appliance . Journal of Clinical
Orthodontics 16 : 663 – 667
Kerr W J S , Ford J 1986 A comparison of facial form in three western
European male groups . European Journal of Orthodontics 8 : 106 – 111
Kuroe K , Rosas A , Molleson T 2004 Variation in the cranial base orientation
and facial skeleton in dry skulls sampled from three major populations .
European Journal of Orthodontics 26 : 201 – 207
Manfredi C , Cimino R , Trani A , Pancherz H 2001 Skeletal changes of
Herbst appliance therapy investigated with more conventional
cephalometrics and European norms . Angle Orthodontist 71 : 170 – 176
Martin R , Saller K 1959 Lehrbuch der Antropologie, Band II. Gustav
Fischer Verlag , Stuttgart , pp. 1283 – 1284
McNamara Jr J A , Howe R P , Dischinger T G 1990 Comparison of the
Herbst and Fränkel appliances in treatment of Class II malocclusion .
American Journal of Orthodontics and Dentofacial Orthopedics 98 :
134 – 144
Pancherz H 1979 Treatment of Class II malocclusions by jumping the bite
with the Herbst appliance. A cephalometric investigation . American
Journal of Orthodontics 76 : 423 – 442
Pancherz H 1982 The mechanism of Class II correction in Herbst appliance
treatment. A cephalometric investigation . American Journal of
Orthodontics 82 : 104 – 113
Paulsen H U 1997 Morphological changes of the TMJ condyles of 100
patients treated with the Herbst appliance in the period of puberty to
adulthood: a long-term radiographic study . European Journal of
Orthodontics 19 : 657 – 668
Paulsen H U , Rabøl A , Sørensen S S 1998 Bone scintigraphy of human
tempomandibular joints during Herbst treatment: a case report . European
Journal of Orthodontics 20 : 369 – 374
Ricketts R 1957 Planning treatment on the basis of the facial pattern and as
an estimate of its growth . Angle Orthodontist 27 : 14 – 37
Riolo M L , Moyers R E , McNamara Jr J A , Hunter W S 1974 An atlas of
craniofacial growth . Monograph No. 2, Craniofacial Growth Series.
Center for Human Growth and Development, University of Michigan ,
Ruf S , Pancherz H 1999 Temporomandibular joint remodeling in
adolescents and young adults during Herbst treatment: a prospective
longitudinal magnetic resonance imaging and cephalometric radiographic
investigation . American Journal of Orthodontics and Dentofacial
Orthopedics 115 : 607 – 618
Schaefer A T , McNamara Jr J A , Franchi L , Baccetti T 2004 A
cephalometric comparison of treatment with the Twin-block and
stainless steel crown Herbst appliances followed by fi xed appliance
therapy . American Journal of Orthodontics and Dentofacial Orthopedics
126 : 7 – 15
Schwarz A M 1934 Erfahrungen mit dem Herbstchen Scharnier zur
Behandlung des Distalbisses . Zahnärztliche Rundschau 43 : 47 – 99
Solow B , Sarnäs K V 1982 A comparison of the adult Swedish and Danish
craniofacial morphology . Swedish Dental Journal (Supplement 1) :
229 – 237
Thilander B , Persson M , Adolfsson U 2005 Roentgen-cephalometric
standards for a Swedish population. A longitudinal study between the
ages of 5 and 31 years . European Journal of Orthodontics 27 : 370 – 389
Valant J R , Sinclair P M 1989 Treatment effects of the Herbst appliance .
American Journal of Orthodontics and Dentofacial Orthopedics 95 :
138 – 147
Voudouris J C , Woodside D G , Altuna G , Kuftinec M M , Angelopoulos
G , Bourque P J 2003a Condyle-fossa modifi cations and muscle
interactions during Herbst treatment, part 1. New technological
methods . American Journal of Orthodontics and Dentofacial
Orthopedics 123 : 604 – 613
Voudouris J C , et al. 2003b Condyle-fossa modifi cations and muscle inter-
actions during Herbst treatment, part 2. Results and conclusions .
American Journal of Orthodontics and Dentofacial Orthopedics 124 :
13 – 29
Wenzel A , Droschl H , Melsen B 1984 Skeletal maturity in Austrian
children assessed by the G-P and the TW-2 methods . Annals of Human
Biology 11 : 173 – 177
Wieslander L 1984 Intensive treatment of severe Class II malocclusions
with a headgear-Herbst appliance treatment in the early mixed dentition .
American Journal of Orthodontics 86 : 1 – 13
Wong G W K , So L L Y , Hägg U 1997 A comparative study of sagittal
correction with the Herbst appliance in two different ethnic groups .
European Journal of Orthodontics 19 : 195 – 204
Woodside D G , Metaxas A , Altuna G 1987 The infl uence of functional
appliance therapy on glenoid fossa remodeling . American Journal of
Orthodontics and Dentofacial Orthopedics 92 : 181 – 198
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