Open Journal of Stomatology, 2011, 1, 36-44 OJST
doi:10.4236/ojst.2011.12007 Published Online June 2011 (http://www.SciRP.org/journal/OJST/).
Published Online June 2011 in SciRes. http://www.scirp.org/journal/OJST
Extractive orthopaedic treatment to compensate for skeletal
Class III in preadolescents
Chiusolo Carmine, Gennaro Caiazzo, Luca Lombardo, Maria Paola Guarneri, Giuseppe Siciliani
Postgraduate School of Orthodontics of Ferrara, Ferrara, Italy.
Received 11 March 2011; revised 13 April 2011, accepted 30 April 2011.
ABSTRACT
Objective: To evaluate the efficacy of extractive or-
thopaedic orthodontic treatment in mixed late denti-
tion in two female patients presenting Class III mal-
occlusion and hyperdivergent facial types due to
maxillary retrusion. Materials and Methods: The or-
thopaedic phase, carried out using posteroanterior
extraoral traction combined with rapid palatal ex-
panders, was followed by extraction of four premo-
lars and application of bidimensional technique fixed
appliances (Boston University). Results: We achieved
functional and aesthetic improvement via normalisa-
tion of the transversal dimensions and a sagittal in-
crease in the maxilla while maintaining vertical sta-
bility. The extractions permitted resolution of the
crowding problem and normalisation of the overbite
and overjet, and Class I molar and canine occlusion
was achieved. Conclusions: Timely intervention and
exploitation of extractive space to compensate for
skeletal alterations using only orthopaedic orthodon-
tic treatment can allow achievement of excellent re-
sults.
Keywords: Extractive; Orthopaedic; Treatment
1. INTRODUCTION
Class III malocclusion may involve the dental compo-
nent alone or it may be aggravated by a poor relationship
between the maxillary and mandibular bases. In the for-
mer case, the lower molar is positioned half a cuspid
towards the midline with respect to the upper molar,
without skeletal alteration, whereas the latter type also
involves a poor relationship between maxilla and man-
dible on the sagittal plane caused by maxillary retrusion
and/or mandibular protrusion [1]. Patients presenting a
sagittally reduced maxilla also frequently show skeletal
contraction of this jaw on the transversal plane [2]. The
majority of Class III patients present both dentoalveolar
and skeletal components [3-5].
Various factors are implicated in the aetiology of
Class III, namely heredity (e.g. race), environmental
factors (e.g. functional anterior deviation of the mandi-
ble or mouth breathing, which can be a positive stimulus
for mandibular growth), and several pathologies (e.g.
pituitary tumours responsible for acromegaly) [6].
The incidence of this type of malocclusion in Cauca-
sian populations varies between 1 and 5 %, in Asian
populations it reaches an upper range which fluctuates
between 9% to 19%, and in Latin populations it is
roughly 5% [7 , 8] .
Early treatment of Class III malocclusion reduces the
necessity of a second phase of treatment in permanent
dentition [1]. Howev er, successful orthodontic treatment
of Class III preadolescents depends not only on adequate
timing but also on individual growth. In fact, the deci-
sion to treat patients with moderate to severe skeletal
Class III early on, or to wait until the end of growth, is a
difficult one, especially as it cannot be predicted wh eth er
growth will permit successful development of the de-
sired skeletal modifications following orthopaedic or-
thodontic treatment [9].
Several studies have reported that Class III skeletal
discrepancies worsen with age [10,11]. Thus the diffi-
culty in treating preadolescent patients successfully in-
creases with time. Nonetheless, the majority of patients
presenting severe skeletal Class III are candidates for
orthognathodontic surgery, the only means of obtaining
functional occlusion and aesthetic profile [12].
In early diagnosis of Class III malocclusion with max-
illary deficiency in late deciduous dentition or early
mixed dentition, the combination of a rapid palatal ex-
pander with posteroanterior traction is a useful treatment
option [13]. This traction is of ten used in synergy with a
maxillary expander in preadolescent patients as this de-
vice is presumed to act by opening the circumaxillary
sutures and thus facilitate the orthopaedic effect of facial
traction [14-16]. However, if the skeletal discrepancy is
caused by excessive mandibular growth, this device seems
to be of scarce therapeutic action as the impossibility of

C. Carmine et al. / Open Journal of Stomatology 1 (2011) 36-44 37
inhibiting of mandibular growth has been proven [17],
and orthognathic surgery is the sole valid option for re-
positioning the mandible once growth is complete.
According to McNamara, the optimum period for ini-
tiating this orthopaedic treatment in Class III cases is in
early mixed dentition [18]. Hickham on the other hand
suggests that this treatment be commenced before the
patient reaches eight years of age [19]. Proffit recom-
mends that anterior retraction be started before the pa-
tient is 9 nine years old in order to produce major skele-
tal changes and minor dental movements [1]. Merwin et
al. stated that this treatment should be begun before the
patient reaches 8 years of age, or b etw een 8 an d 1 2 years
in mixed dentition, in order to obtain more skeletal than
dental modifications, ach ieving similar results in the two
groups analysed [20]. Baccetti and McNamara verified
craniofacial skeletal changes resulting from this ortho-
paedic treatment in both early and late mixed dentition,
finding more significant results in the former group. In a
review by Baccetti et al., the percentage of success was
found to be 76% higher when the orthopaedic treatment
plan, including extraoral traction and rapid palatal ex-
pansion, was used to treat Class III malocclusions in
preadolescent pati ent s [2 1] .
In this context we proposed to analyse the dentoske-
letal changes revealed in two patients with Class III mal-
occlusion due to maxillary retrusion and mandibular
protrusion, treated in late mixed dentition. As both pa-
tients presented moderate, and not severe, Class III-type
growth, the abovementioned orthopaedic treatment (rapid
expansion and traction) was applied, followed by the ex-
traction of four premolars, to compensate for the sagittal
skeletal discrepancies. In fact, orthodontic camouflage is
a valid alternative to surgery in patients who do no t pre-
sent severe Class III malocclusion [6].
2. CASE REPORT 1
2.1. Diagnosis
Extraoral clinical examination of the female 13-year-old
patient from the front showed long face, deviation of the
cutaneous pogonion to the right, and mandibular asym-
metry. From the side, a concave profile with evident
collapse of the upper lip from hypopremaxilla could be
seen (Figure 1).
Intraoral examination revealed poor oral hygiene and
slight signs of periodontal damage at element 41 due to
occlusal trauma. The upper arch, in permanent dentition,
was greatly contracted and a space deficit was evident in
the region 15-13-23. The mandibular arch was in late
mixed dentition and crowdi ng was evident in the anterior
section. The sagittal occlu sal relationships deno ted Class
III malocclusion of the molars and canines, a “head-to-
head” interincisive relationship, and cross bite at 12 - 22.
Vertically, anterior open bite was evident and transver-
sally the lower median line was deviated to the left due
to mandibul ar slipping (Figure 2).
Functional examination revealed a dual bite from man-
dibular slipping to the right aggravated by pre-contacts
in the frontal region. The patient reported mixed breath-
ing with frequent episodes of nasal obstruction. Pano-
ramic X-ray evidenced agenesis of element 45 and the
presence of third molar buds. No dentoperiodontal pa-
thology was evident (Figure 3). Cephalometry showed
malocclusion with pathological skeletal characteristics:
the vertical relationships indicated severe skeletal hy-
perdivergence, sagittally the maxilla was retruded, the
inclination of the upper and lower incisors reflected
dental compensation for the skeletal malocclusion, and
the position of the lips was inverted with respect to the
aesthetic line (Figures 4 and 5).
2.2. Treatment Objectives
Analysing the problems evidenced in diagnosis we pro-
posed transversal expansion of the upper jaw to elimi-
nate the pre-contacts deflecting the mandible and to im-
prove respiratory function, orthopaedic advancement of
the upper jaw, resolution of the crowding in both arches,
normalisation of the overjet and overbite, and improve-
ment of the frontal and lateral aesthetic.
2.3. Treatment Progress
The contraction and retrusion of the upper jaw were
treated using a rapid palatal expander and Delaire’s pos-
Figure 1. Extraoral photographs before treatment.
Figure 2. Intraoral photographs before treatment.

C. Carmine et al. / Open Journal of Stomatology 1 (2011) 36-44 38
Figure 3. Panoramic X-ray before treatment.
Figure 4. L-L Teleradiography before treatment.
Figure 5. Cephalometric trace before treatment.
teroanterior traction, respectiv ely. Subsequently the den-
tal elements 14-24-34-85 were extracted and both arches
were fitted with bidimensional technique fixed appli-
ances (Boston University). Alignment was obtained us-
ing 0.016 an d 0.018 × 0.025 pre-formed nickel-titanium
wires, then extraction spaces were closed with 0.016 ×
0.022 steel wires together with class I intramaxillary
elastics and class III intermaxillary elastics. 0.018 ×
0.022 ideal steel wires and vertical intermaxillary elas-
tics were used for finishing. Finally, a Hawley retainer
was employed for the upper arch and a 0.019 twist re-
tainer was used from elements 33 to 43 in the lower.
2.4. Treatment Results
Frontal facial examination of the patient after treatment
showed an improvement in aesthetic balance and sym-
metry of the mandibular position, which, however, re-
tained its characteristics of irregularity of form, and the
patient’s smile was aesthetically pleasing. Lateral ex-
amination revealed a great improvement in profile aes-
thetics, with evident reduction in the nasolabial angle
and re-equilibration of the relationship between upper
and lower jaw (Figure 6). Examination of dentition ex-
posed a Class I molar and canine relationship, normal
overjet and overbite, and normal transversal relation-
ships. Oral hygiene had improved and the periodontal
situation at element 41 at the beginning of treatment was
better (Figure 7). Functional examination highlighted a
good incisive and canine guide, and the opening move-
ments, laterality and protrusion had normalised. Ortho-
pantomography evidenced slight inclination of the root
of element 15; the space required for third molar erup-
tion appeared to be present (Figure 8). Cephalometric
values showed sagittal improvement and vertical stabil-
ity. Dental relationships were found to be in the norm
(Figures 8, 9 and 10).
Figure 6. Extraoral photographs after treatment.
Valori cefalometrici
Maxilla to Cranial Base
SNA(˚) 76.4 82.0 3.5 –1.6*
Mandible to Cranial Base
SNB (˚) 75.1 80.9 3.4 –1.7*SN
GoGn (º) 48.4 32.9 5.2 3.0***
FMA (MP-FH) (˚) 37.0 26.0 4.5 2.4**
Maxillo-Mandibular
ANB (˚) 1.3 1.6 1.5 –0.2
Maxillary Dentition
U1 - NA (mm) 7.4 4.3 2.7 1.1*
U1 - SN (˚) 104.8 101.6 5.5 0.6
Mandibular Dentition
L1 - NB (mm) 7.8 4.0 1.8 2.1**
L1 - MP (˚) 80.2 95.0 7.0 –2.1**
Soft T i ssue
Lower Lip to E-Plane (mm)0.7 –2.0 2.0 1.4*
Upper Lip to E-Plane (m m)–7.7 1.0 2.0 –4.7****

C. Carmine et al. / Open Journal of Stomatology 1 (2011) 36-44 39
Figure 7. Intraor al photog raphs after treatment.
Figure 8. Panoramic X-ray after treatment.
Figure 9. Cephalometric trace after treatment.
Figure 10. Superimpos ition of pre- and post-treatment cephalometric traces at the cranial
base, passing through points S an d N. Superimpositions of the upper jaw were calculated
on the bispinal plane, and superimpositions of the mandible on the gonion-menton plane.
Valori cefalometrici
Maxilla to Cranial Base
SNA(˚) 77.8 82.0 3.5 –1.2*
Mandible to Cranial Base
SNB (˚) 75.5 80.9 3.4 –1.6*SN
GoGn (˚) 44.9 32.9 5.2 2.3***
FMA (MP-FH) (˚) 36.8 25.1 4.5 2.6**
Maxillo-Mandibular
ANB (˚) 2.3 1.6 1.5 0.5
Maxillary Dentition
U1 - NA (mm) 5.6 4.3 2.7 0.5
U1 - SN (˚) 105.5 102.4 5.5 0.6
Mandibular Dentition
L1 - NB (mm) 6.9 4.0 1.8 1.6*
L1 - MP (˚) 79.8 95.0 7.0 –2.2**
Soft T i ssue
Lower Lip to E-Plane (mm)–2.4 –2.0 2.0 –0.2
Upper Lip to E-Plane (m m)–7.0 –3.5 2.0 –1.7*

C. Carmine et al. / Open Journal of Stomatology 1 (2011) 36-44 40
3. CASE REPORT 2
3.1. Diagnosis
The female 13-year-old patient showed a deviation of
the menton to the right, a concave profile with short and
retruded upper lip, and poorly accentuated zygomatic
bone upon clinical examination (Figure 11). The con-
tracted upper arch was in permanent dentitio n and a spa-
tial deficit was evident in the regions of elements 12-13-
15-22-23. The mandibular arch was in late mixed denti-
tion and crowding was noted in the anterior region.
Analysis of the occlusion sagittally showed a Class II
molar and canine relationship and cross bite throughout
the anterior section, while open bite in the median sec-
tion was noted upon vertical analysis and deviation of
the lower median line to the right due to mandibular
slipping was seen on the transversal plane (Figure 12).
Functional examination revealed dual bite from man-
dibular slipping to the right due to pre-contacts. The
patient reported mixed breathing with frequent episodes
of nasal obstruction. Panoramic X -ray showed third mo-
lar buds. No evidence of dentoperiodontal pa t hol o gy was
noted (Figure 13). Malocclusion with characteristics of
skeletal pathology was observed by cephalometry; the
vertical relationships showed severe skeletal hyperdi-
vergence, wh ile from the sagittal perspective the maxilla
was revealed to be retruded, the inclination of the upper
and lower incisors reflected dental compensation for the
skeletal malocclusion and an inverted position of the lips
with respect to the aesthetic line (Figure 14).
Figure 11. Extraoral photographs before treatment.
Figure 12. Intraoral photographs before treatment.
Figure 13. Panoramic X-ray before treatment.
Figure 14. L-L teler adiogra phy before treatmenent.
3.2. Treatment Objectives
We proposed to treat the problems evidenced in the di-
agnosis using transversal expansion of the upper jaw,
with elimination of the pre-contacts deflecting the man-
dible and improvement of respiratory function, ortho-
paedic advancement of the upper jaw, resolution of up-
per and lower crowing, normalisation of overjet and
overbite, and improvement of the frontal and lateral aes-
thetic of the face.

C. Carmine et al. / Open Journal of Stomatology 1 (2011) 36-44 41
Figure 15. Cephalometric trace before treatment.
3.3. Treatment Progress
A rapid palatal expander and Delaire’s posteroanterior
traction were used to treat the contraction and retrusion
of the upper jaw, respectively. The patient then under-
went extraction of dental elements 14-24-34-44 and bidi-
mensional technique fixed appliances (Boston Univer-
sity) were applied to both arches. 0.016 and 0.018 ×
0.025 pre-formed nickel-titanium archwires were em-
ployed in alignment, and 0.016 × 0.022 steel wires with
class I intramaxillary elastics and class III intermaxillary
elastics were used to close the extraction spaces. Ideal
0.018 × 0.022 steel wires and vertical intermaxillary ela-
stics were used for finishing, and retention was achieved
by a Hawley retainer in the upper arch an d a 0.019 twist
retainer from elements 33 to 43 in the lower.
3.4. Treatment Results
Facial examination from the front upon termination of
treatment showed better aesthetic balance and mandibu-
lar symmetry, and the patient had an aesthetically pleas-
ing smile. Lateral examination showed a much improved
profile aesthetic, an evident reduction in the nasolabial
angle and a re-equilibration of the relationship between
upper and lower lip (Figure 16). Dental examination
showed Class I molar and canine relationship, and nor-
mal overjet, overbite and transversal relationships (Fig-
ure 17). Functional examination showed a good incisive
and canine guide, and normal opening movements, late-
rality and protrusion. Orthopantomographical analysis
revealed a slight mesioinclination of the root of element
15 and the presence of space for third molar eruption
(Figure 18). Cephalometric values demonstrated sagittal
improvement and vertical stability. Dental relationships
were normal (Figures 19 and 20).
4. DISCUSSION
The two cases analysed and treated both presented the
Figure 16. Extraoral photographs after treatment.
Figure 17. Intraoral photographs after treatment.
Valori cefalometrici
Maxilla to Cranial Base
SNA(˚) 71.7 82.0 3.5 –2.9**
Mandible to Cranial Base
SNB (˚) 74.0 80.9 3.4 –2.0**SN
GoGn (˚) 41.3 32.9 5.2 1.6
FMA (MP-FH) (˚) 31.0 26.0 4.5 1.1**
Maxillo-Mandibular
ANB (˚) –2.3 1.6 1.5 –2.6**
Maxillary Dentition
U1 - NA (mm) 6.5 4.3 2.7 0.8
U1 - SN (˚) 94.9 101.4 5.5 –1.2*
Mandibular Dentition
L1 - NB (mm) 4.9 4.0 1.8 0.5
L1 - MP (˚) 81.7 95.0 7.0 –1.9*
Soft T i ssue
Lower Lip to E-Plane (mm)–2.4 –2.0 2.0 –0.2
Upper Lip to E-Plane (mm)–7.8 3.2 2.0 5.5*****

C. Carmine et al. / Open Journal of Stomatology 1 (2011) 36-44 42
Figure 18. Panoramic X-ray after treatment.
Figure 19. L-L teleradiography after
treatmen.
Figure 20. Cephalometric trace.
Figure 21. Superimposition of pre- and post-treatment cephalometric traces
at the cranial base, passing through points S and N. Superimpositions of the
upper jaw were calculated on the bispinal plane, and superimpositions of the
mandible on the gonion-menton plane.
Valori cefalometrici
Maxilla to Cranial Base
SNA(˚) 73.3 82.0 3.5 –2.5**
Mandible to Cranial Base
SNB (˚) 73.6 80.9 3.4 –2.2**SN
GoGn (˚) 41.9 32.9 5.2 1.7*
FMA (MP-FH) (˚) 30.5 26.0 4.5 1.0*
Maxillo-Mandibular
ANB (˚) –0.3 1.6 1.5 –1.2*
Maxillary Dentition
U1 - NA (mm) 6.3 4.3 2.7 0.8
U1 - SN (˚) 96.2 101.4 5.5 –0.9
Mandibular Dentition
L1 - NB (mm) 3.8 4.0 1.8 –0.1
L1 - MP (˚) 81.9 95.0 7.0 –1.9*
Soft T i ssue
Lower Lip to E-Plane (mm)–6.8 –2.0 2.0 –2.4**
Upper Lip to E-Plane (mm)–10.4 3.2 2.0 –6.8****

C. Carmine et al. / Open Journal of Stomatology 1 (2011) 36-44 43
characteristics of third class malocclusion with a den-
toskeletal component characterised by maxillary retru-
sion and mandibular protrusion. These characteristics
were noted upon clinical examination and subsequently
confirmed by cephalometric analysis. Considering the
type of malocclusion and the age of the patient, we de-
cided to intervene immediately with the abovementioned
orthopaedic treatment, using a rapid expander to correct
the transversal dimension of the maxilla and postero-
anterior extraoral traction to correct the sagittal discrep-
ancy. From the literature it can be evinced that the best
period to commence this treatment is early mixed denti-
tion and Merwin et al. demonstrated that the skeletal
effects of this orthopaedic treatment are evident up to 12
years of age [20].
Following on from these studies we applied these de-
vices to patients who had just turned 13 in an attempt to
open up their mandibular sutures. The treatment met
with success and evident skeletal changes were seen:
post-treatment cephalometry revealed an increase in the
SNA angle of about 1.5˚ in both cases treated, while the
SNB did not change appreciably. This result was due to
the growth induced in the upper jaw which compensated
for the mandibular excess. Extraction compensated for
the sagittal skeletal discrepancy, normalising the overjet
and overbite relationship. Furthermore the extractions
allowed us to resolve the crowding in both arches. Su-
perimposition of the pre- and post-treatment traces
showed the effect of the extractions, which permitted
retrusion of the incisors and advancement of the molar,
consenting achievement of the first class dental molar
and canine relationship. From the superimpositions and
cephalometric values it can be observed that the incisors
underwent a bodily m ovem ent without si gnificant changes
in their buccal-lingual inclination. The transversal ex-
pansion of the maxilla also permitted improvement of
the patient as well as function, eliminating the obstacles
deflecting the mandible. Correction of the anterior sector
permitted resolution of the signs of periodontal damage
seen prior to treatment in the first case.
The satisfactory occlusion and the appreciable aes-
thetic results obtained were due to the young age of the
patients treated, the choice of extraction for dentoalveo-
lar compensation and to good collaboration in the appli-
cation of traction and inter and intramaxillary elastics.
5. CONCLUSIONS
Our study proposed to evaluate the efficacy of orthopae-
dic treatment carried out with a rapid palatal expander
and Delaire’s posteroanterior extraoral traction in two
growing patients presenting Class III malocclusion char-
acterised by maxillary retrusion. At the end of treatment
it was possible to appreciate the efficacy of these devices
in normalising the sagittal and transversal discrepancies
of the maxillary and mandibular bases an d balancing the
profile, thus obtaining a satisfactory aesthetic. Having
exploited the patients’ young age (acting with the correct
timing) and used the extractive space to compensate for
skeletal alterations, we achieved excellent results with-
out surgery, which would probably have been necessary
to achieve comp arable results in an older patient.
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