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ABSTRACT : The following case report is of a 19 year-old female patient who presented with Angle's
Class III malocclusion and anterior crossbite on a Skeletal class III base with a hypodivergent growth
pattern. There was gingival recession with respect to her lower right central incisor which was severe for
her age and in part, caused by the crossbite malocclusion. No CO-CR discrepancy was noted. The objective
of the orthodontic treatment was correction of the Class III malocclusion, correction of the anterior
crossbite, restoration of the periodontal health of compromised central incisor and improvement of facial
esthetics. Treatment consisted of fixed orthodontic mechanotherapy using preadjusted edgewise
appliance. Results showed a marked improvement in the occlusal harmony and facial esthetics.
1 2Dr.Mohammad Tariq , Dr.Sarah Asif 1Professor& Chairman, Department of Orthodontics and Dentofacial Orthopedics,
Ziauddin Ahmad Dental College, Aligarh Muslim University, Aligarh2Senior Resident, Department of Orthodontics and Dentofacial Orthopedics,
Ziauddin Ahmad Dental College, Aligarh Muslim University, Aligarh
INTRODUCTION :
Moyer's defined anterior tooth crossbite as a dental
malocclusion resulting from the abnormal axial inclination of
maxillary anterior teeth.[1] Correction of crossbite is
recommended when it is seen for the first time because it
eliminates functional shifts and wear on the erupted
permanent teeth, and possibly dentoalveolar asymmetry
which eventually increases arch circumference providing
sufficient space for the permanent teeth to erupt. An early
correction of developing or a frankly developed crossbite also
makes future treatment more comprehensible by eliminating
at least that problem from the list.[2,3,9]
Though lack of an adequate space for the maxillary incisors to
erupt is considered to be one of the most common cause of
anterior crossbite, it is also seen to develop due to a labially
positioned supernumerary tooth causing lingual deflection of
the permanent tooth or any trauma causing displacement of
the developing permanent tooth germ or an arch-length
deficiency causing a lingual deflection of permanent anterior
teeth during eruption or any habit of biting upper lip or in case
of repaired cleft lip.[4,5,9]
Anterior crossbites require an immediate and effective
treatment to prevent anterior teeth mobility and fracture and
also to obviate any future periodontal and temporomandibular
joint disturbances.[6-8]
Depending upon the etiology of the anterior crossbite;
skeletal or dental, and the stage of dentition; mixed or
permanent, a variety of treatment approaches can be used to
prevent, intercept or correct it. A meticulous diagnosis must
be performed by the orthodontist before beginning with the
treatment mechanics.[9]
Treatment modalities for correction of anterior crossbite
include tongue blade therapy, inclined plane, removable
appliance with finger spring, maxillary 2x4 appliance,
bonded resin-composite slopes, fixed orthodontic
mechanotherapy or orthognathic surgical procedures.9-10
CORRECTION OF ANTERIOR CROSSBITE IN
A FEMALE ADULT PATIENT- A CASE REPORT
Journal of Dental Sciences
University
University Journal of Dental Sciences, An Official Publication of Aligarh Muslim University, Aligarh. India 70
University J Dent Scie 2018; Vol. 4, Issue 3
CaseReport
Key words:
Anterior Crossbite,
Class III Skeletal Base,
CO-CR discrepancy.
Conflict of interest: Nil
No conflicts of interest : Nil
This case report describes the effective correction of anterior
crossbite in an adult using fixed orthodontic mechanotherapy.
CASE REPORT ;
A 19 years old female patient presented with chief complaint
of forwardly and irregularly placed upper front teeth and a non
pleasing smile. Upon the initial extraoral clinical
examination, she exhibited a symmetrical mesoprosopic face
with concave profile and prominent chin. Smile analysis
revealed a non-consonant smile arc with a low smile line and
Morley's ratio of 70%. (Figure 1)
The intraoral examination revealed a bilateral Angle's Class
III molar and canine relationship and anterior crossbite with
respect to 11,12 & 41,42,43. The facial as well as the dental
midlines were coincident. The maxillary arch was symmetric
and U shaped with palatally placed 11 &12 and rotated 13
&23. The mandibular arch was symmetric and U-shaped with
spacing between 31 &41.The mandibular right central incisor
was associated with grade II mobility and gingival recession.
The functional findings revealed no signs or symptoms of
temporomandibular disorder. Upon further examination there
was absence of any occlusal interferences or an anterior shift
from centric relation (CR) to centric occlusion (CO) during
mandibular closure.
Cephalometric findings revealed a Skeletal class III relation
(SNA=78°, SNB=79°, ANB=-1°, Wits= 0 mm). The patient
had a hypodivergent growth pattern (FMA=19° and Gonial
angle=119 °). The dentoalveolar findings suggested normally
positioned maxillary incisors and retroclined mandibular
incisors (Max 1-Na=6.5mm, Max 1-NA=30°, Mand 1-APog=
1mm, IMPA=88° and Interincisal angle= 135°). Soft tissue
cephalometric analysis revealed retrusive upper and lower lip
w.r.t S and E line. (Figure 2& 5)
Model analysis revealed a total discrepancy of 4mm in the
maxillary arch and 1 mm in the lower arch.
TREATMENT GOALS :
The goals were to obtain a good facial balance with
optimum static and functional occlusion. The treatment
objectives were:
· Correction of Anterior Crossbite
Leveling and alignment of arches
Correction of Overjet and Overbite
Achieving Class 1 Molar and canine relation B/L
Correction of gingival recession & mobility w.r.t 41
Retention
TREATMENT PLAN :
The treatment plan proposed was non extraction fixed
orthodontic mechanotherapy.
TREATMENT SEQUENCE :
The patient underwent fixed orthodontic mechanotherapy
with MBT preadjusted edgewise appliance (0.022x 0.028
inch slot). A removable lower acrylic posterior bite plate was
used to disocclusion so that the palatally positioned incisors
could be moved forward. In the intial step of leveling and
alignment only upper bonding and banding was done. An
initial 0.016-inch round nickel titanium arch wire was placed
for the alignment of the upper arch. At the end of 16 weeks,
alignment of the upper anteriors was complete and the upper
incisors which were in crossbite had been moved out
successfully. Also at this stage, lower arch bonding and
banding was done and the use of posterior bite plate was
discontinued.
Upon completion of the alignment and progression to 0.019 x
0.025 inch stainless steel wires in both maxillary and
mandibular arch, class III force was applied using elastics.
Settling elastics were used for three weeks following which
the patient was debonded and removable upper and lower
retainers were given.
RESULTS :
The final outcome showed attainment of all functional and
·····
University Journal of Dental Sciences, An Official Publication of Aligarh Muslim University, Aligarh. India 71
University J Dent Scie 2018; Vol. 4, Issue 3
esthetic goals. The radiographic evaluation confirmed the
correction of the inclination of upper and lower incisors. An
ideal amount of overjet and overbite were established and
crossbite corrected. Also, after successful completion of the
fixed orthodontic treatment, there was marked improvement
in the periodontal condition of the lower right central incisor.
The mobility was reduced to grade 0 and a significant amount
of bone formation was noted on the periapical radiograph
around the lower central incisor. (Figure 3&4)
DISCUSSION:
Balanced facial esthetics with a harmonious soft tissue profile
and a stable occlusion along with functional considerations
are considered to be one of the most important objectives of
orthodontic therapy. An anterior crossbite detected in the
mixed dentition is usually an alarming situation for the
orthodontist since it may adversely restrict the forward
maxillary alveolar growth and further complicate the
crowding of the maxillary anterior teeth in patients with arch
length deficiency problems. For these reasons, anterior
crossbites are said to be corrected as soon as they are
discovered.[10-11]
While attempting the correction of anterior crossbite certain
variables are to be considered.
Firstly, the presence or absence of an anterior shift from
centric relation to centric occlusion during mandibular
closure should be diagnosed. Patients with an anterior shift
are categorized as pseudo Class III and usually have a Class I
molar relationship in CR. When no anterior shift is detected,
the probability increases that a true Class III malocclusion is
present, and also that the anterior crossbite has an underlying
skeletal discrepancy. Secondly, anterior arch length must be
assessed while attempting to align the maxillary incisor in
palatal crossbite. If inadequate arch length is available, first
attempt must be made to create sufficient space. During fixed
appliance orthodontic mechanotherapy, open coil springs are
often utilized for space regaining in order to move the teeth
out of crossbite. However in cases of severe crowding,
extractions are documented. Thirdly, correction of the torque
of the roots of the maxillary incisor roots which were in
crossbite, is almost always required, since the teeth in
crossbite have their roots positioned lingually and the long
axis of these teeth is in a greater labial inclination than normal
which is more likely to relapse following treatment. Hence,
for the correction and better control of torque, brackets with
built-in torque are used in an inverted fashion and bonded on
the labial surface of the crown.
Lastly, the alignment of mandibular anterior teeth should
always be delayed until the maxillary anterior teeth have been
moved out of crossbite. [9-11]
CONCLUSION :
Thorough diagnosis and careful treatment planning along
with appropriate execution of the orthodontic mechanics is
the surest way to achieve successful and predictable results
with minimal side effects. A remarkable improvement in the
University Journal of Dental Sciences, An Official Publication of Aligarh Muslim University, Aligarh. India 72
University J Dent Scie 2018; Vol. 4, Issue 3
dental and soft tissue profile as well as the self-esteem of the
patient was seen.
REFERENCES
1. Moyers, R.E. Handbook of Orthodontics, 4th ed, Year
Book Medical Publishers, Inc; Chicago, 1988, pg 418.1.
2. Langberg BJ, Arai K, Miner RM. Transverse skeletal and
dental asymmetry in adults with unilateral lingual
posterior crossbite. Am J Orthod Dento Orthop 127:6-
15,2005.
3. Adkins MD, Nanda RS, Currier GF. Arch perimeter
changes on rapid palatal expansion. Am J Orthod 97:10-
19,1990.
4. Mc Donald, Dentistry for the Child and Adolescent, 8th
Ed.,Elsevier, a division of Reed Elsevier India Pvt. Ltd.,
2005, chap.27 pg. 651-653.
5. Lee BD. Correction of crossbite. Dent Clin North Am.
1978 Oct; 22(4):647-68.
6. Valentine F, Howitt JW.Implications of early anterior
crossbite correction. ASDC J Dent Child. 1970 Sep-Oct;
37(5):420-7.
7. Estreia F, Almerich J, Gascon F. Interceptive correction
of anterior crossbite. J Clin Pediatr Dent. 1991 Spring;
15(3):157-9.
8. Jacobs SG.Teeth in cross-bite: the role of removable
appliances.Aust Dent J. 1989 Feb;34(1):20-8.
9. Profit WR. Contemporary orthodontics. Mosby, 4th
edition, 2007.
10. Graber TM. Orthodontics: Principles and Practice. W. B.
Saunders, Philadelphia, Pa, USA, 5th edition, 2012
11. Bishara SE.Textbook of orthodontics.W.B. Saunders,
Philadelphia, Pa, USA, 2001.
CORRESPONDING AUTHOR:
Dr. Sarah Asif
Senior Resident,
Department of Orthodontics and Dentofacial Orthopedics,
Dr.Ziauddin Ahmad Dental College, Aligarh Muslim
University, Aligarh, Uttar Pradesh, India, Pincode -202002
Email : [email protected]
Contact number : 09634319370
University Journal of Dental Sciences, An Official Publication of Aligarh Muslim University, Aligarh. India 73
University J Dent Scie 2018; Vol. 4, Issue 3