Two-stage treatment of skeletal Class III
malocclusion during the early permanent
Jiuhui Jiang,aJiuxiang Lin,band Changrong Jic
A patient with skeletal Class III malocclusion was treated in 2 phases during the early permanent dentition.
In phase 1, maxillary protraction was combined with rapid palatal expansion; in phase 2, fixed appliances
were placed. The results were good posttreatment, and, 1 year later, a favorable growth tendency could be
observed. This report shows that treatment for a patient with skeletal Class III malocclusion can be started
in the early permanent dentition, with very good final results. (Am J Orthod Dentofacial Orthop 2005;128:
protruded mandible. Many clinicians successfully treat
these patients with maxillary protraction and palatal
expansion.1-5 Generally, treatment starts during the
early mixed or late deciduous dentition,6 and it is
recommended that early treatment (phase 1) be started
as early as possible for a more favorable result.5,7 But
the long-term stability of phase 1 treatment for Class III
patients is still unclear, and relapse can occur. It seems
that the earlier we start phase 1 treatment, the more
problematic it becomes to maintain long-term stability.
We decided to begin treatment for this patient in the
early permanent dentition stage, hoping to reduce
o s t patients with developing Class III maloc-
clusion display anterioposterior (A-P) maxil-
lary deficiency with a normal to slightly
DIAGNOSIS AND ETIOLOGY
The patient was a girl, aged 11 years 3 months,
whose chief complaints were crowding and anterior
crossbite (Figs 1-5). Her medical history was unre-
markable. Her father had edge-to-edge anterior occlu-
sion. The patient had a concave profile with maxillary
deficiency. Her mandible could not move into edge-to-
edge anterior occlusion. Her permanent dentition had
erupted up to the mandibular second molars, and she
had a persistent mandibular left second deciduous
molar. There was 5 mm of crowding in the maxillary
arch but almost none in the mandible. Her incisor
relationship was Class III with overjet of ?2 mm and
complete overbite of 4 mm. The maxillary midline was
coincident with the face, but the mandibular midline
was deviated 1 mm to the right. The molar relationships
were full Class III on both sides.
The panoramic film showed all 4 third molars
unerupted. The lateral cephalometric radiograph and
tracing showed a skeletal Class III relationship with
maxillary retrusion and a little mandibular protrusion
The following objectives were identified: improve
the soft tissue profile, correct the A-P skeletal discrep-
ancy and the anterior crossbite, establish Class I canine
and molar relationships, correct the midline, align the
teeth, and coordinate the arch forms.
A chincap appliance could be used during phase 1
treatment, but Sugawara et al8 showed that Class III
patients treated early with chincaps alone have latent
catch-up of mandibular displacement in a forward and
downward direction. In addition, this modification
treatment might not be suitable for Class III malocclu-
sion patients with maxillary retrusion.
A second option was to wait until growth had
ceased and then use dental camouflage treatment or
orthognathic surgery. However, some patients and their
parents reject orthognathic treatment, and, after growth
aLecturer, Department of Orthodontics, School of Stomatology, Peking Uni-
versity, Beijing, China.
bProfessor, Department of Orthodontics, School of Stomatology, Peking
University, Beijing, China.
cProfessor, Department of Orthodontics, School of Stomatology, Capital
University of Medical Sciences, Beijing, China.
Reprint requests to: Dr Jiuhui Jiang, Department of Orthodontics, Peking
University, School of Stomatology, 23 Zhongguancunnandajie, Haidian Dis-
trict, Beijing, 100081, China; e-mail, firstname.lastname@example.org.
Submitted, August 2003; revised and accepted, March 2004.
Copyright © 2005 by the American Association of Orthodontists.
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American Journal of Orthodontics and Dentofacial Orthopedics
Volume 128, Number 4
Jiang, Lin, and Ji 527