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International Journal of Research in Medical Sciences | April 2024 | Vol 12 | Issue 4 Page 1344
International Journal of Research in Medical Sciences
Portillo FRL et al. Int J Res Med Sci. 2024 Apr;12(4):1344-1348
www.msjonline.org
pISSN 2320-6071 | eISSN 2320-6012
Review Article
Dental crowding: a review
Fernando Rosas López Portillo1, Jesús Gámez Valenzuela2, Víctor Manuel Rosas Alcaraz1,
Aurea Elizabeth Valle Urias1, Daniela Del Rosario Martínez Pérez1,
Félix Manuel Manjarrez Guerrero1, Gloria Elena Guzmán Celaya1,
Tonantzin González Arredondo1, Marco Antonio Quiroz Beltrán1,
Martha Lilia Soberanes Galindo1, Cristhal Duque Urióstegui3*
INTRODUCTION
Dental crowding is a frequent characteristic of dental
malocclusion; this dental characteristic does not
discriminate between sex, race, education, socioeconomic
status/age.1 Some authors consider it normal
physiological phenomenon for all dentitions; temporary,
mixed and permanent, however, late mixed dentition is
when the most severe degree of crowding occurs, which
is why it becomes one of main reasons for dental
consultation.2,3
Dental crowding is the reduction in the perimeter of the
arch that can manifest as space closure, rotation and/or
movement of the teeth.4 Dental crowding is a common
problem and is one of the main causes of dental
consultations worldwide. It is considered a public health
problem due to the high prevalence with which it occurs.
According to the world health organization (WHO), it
occupies the third place among the most prevalent oral
disorders.5,6 Within the spectrum of malocclusion, dental
crowding stands out, which is described as the
discrepancy between the available space and the required
space according to the size and anatomy of the teeth. If
the space is reduced, this can produce crowding and
dental rotations (Figure 1) therefore, the temporary
dentition in this pathology is crucial since it guides the
eruption of the permanent teeth, thus establishing the
ideal occlusion.7,8 The lack of spaces can cause
disproportionate sizes between the jaws and the
permanent teeth.9 The etiology is multifactorial and its
prevalence among growing children and adolescents is
56% and can vary from 31-96% according to geographic
areas and an association has been found with premature
1Department of Stomatology, UAS, Sinaloa, Mexico
2Department of Pediatrics, CIDOCS, UAS, Mexico
3Department of Orthodontics, Nova Wellness Center, Mexico
Received: 14 February 2024
Accepted: 29 February 2024
*Correspondence:
Dr. Cristhal Duque Urióstegui,
E-mail: cristhalduque@gmail.com
Copyright: © the author(s), publisher and licensee Medip Academy. This is an open-access article distributed under
the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial
use, distribution, and reproduction in any medium, provided the original work is properly cited.
ABSTRACT
Dental crowding is a frequent characteristic of dental malocclusion and is the reduction in the perimeter of the arch
that can manifest as space closure, rotation and/or movement of the teeth. The temporary dentition is important as it
guides the eruption of the permanent teeth, thus establishing the ideal occlusion; the lack of spaces can cause
disproportionate sizes between the jaws and the permanent teeth. Treatment options include the orthopedic phase and
orthodontic phase in which the extraction of teeth may or may not be necessary. Timely treatment with personalized
planning helps us achieve correct dental occlusion, which is essential for good chewing and correct passage of the
bolus, in addition to playing an important role for phonation and the aesthetic results for the patient.
Keywords: Dental crowding, Dental malocclusion, Tooth eruption, Temporary dentition, Orthopedic phase,
Orthodontic phase
DOI: https://dx.doi.org/10.18203/2320-6012.ijrms20240664
Portillo FRL et al. Int J Res Med Sci. 2024 Apr;12(4):1344-1348
International Journal of Research in Medical Sciences | April 2024 | Vol 12 | Issue 4 Page 1345
loss of teeth and even when tooth replacement does not
occur.10 Eruption sequence is essential for correct
development of biomechanical aspects of occlusion,
directly influencing facial growth pattern, skeletal size
relationship, dental morphology, physiological dental
mesialization, dimension of arches, size of apical bone,
perioral muscles, inclination of molars and incisors,
position and inclination of teeth during eruption.11,12
Figure 1: (A) A six-year-old male patient with mixed dentition, premature loss of temporary organs is observed
together with the lack of space for the eruption of permanent teeth; (B) eight-year-old male patient presents with
mixed dentition and dental crowding along with lack of space for tooth eruption; (C) two-year-old male patient, has
temporary dentition, lack of space for tooth eruption is observed; and (D) four-year-old male patient has
temporary dentition, it is observed that he does not have enough space for dental eruption, the space required for
the central teeth is marked with lines in blue, in green for sides and red for canines, without space for premolars.
Researchers from the Kent school of anthropology and
conservation studied 11 globally distributed populations
and discovered that as humans transitioned from a
hunting lifestyle to an agricultural lifestyle, their jaws
became shorter and wider, explaining the high incidence
of crowding. in the modern population.13 Other possible
reasons that have been investigated are crowding in the
anterior area related to lack of space in the dental arch,
premature loss or excessive retention of primary teeth,
excessive length of the canine crown, hereditary factors,
functional alterations of the endocrine glands, tumors,
cysts. To resolve such malocclusion and crowding
originating from space discrepancy, various degrees of
orthodontic treatment can be planned, from simple minor
tooth movement to orthognathic surgery.14
CLASSIFICATION
According to its severity, it is classified as mild,
moderate or severe.
Mild crowding
The dental alveolar discrepancy is 1 to 3 mm, it occurs
during the temporary transition to the permanent one with
greater prevalence in the anterior sector, there is
buccolingual displacement or rotation of some dental
organ.
Moderate crowding
The dental alveolus discrepancy is 3.1 to 5 mm, they have
a pronounced irregularity in the alignment of the incisors.
Severe crowding
The dental socket discrepancy is 5.1 millimeters or more,
generally one or more teeth will be found outside the
arch.15
However, Vander Linden classified crowding according
to the moment in which it appeared in the dentition, thus
establishing the classification into primary, secondary
and tertiary or late crowding since it occurs in the
mandibular incisors during adolescence.16
Little's irregularity index was proposed by Robert Little
in 1975, to quantify the dental crowding that each
individual presents. This method consists of measuring
the linear distance present between the vertical projection
of the anatomical contact points of each of the lower
anterior teeth. The sum of these 5 measures represents the
irregularity index. The instrument used to make the
measurements must be a caliper with a minimum
precision of tenths of a millimeter and its tips must be
fine enough to allow adequate access and precise
measurements. To carry out the measurements, a study
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model of the lower jaw must be obtained, which is placed
on a board to be able to observe the incisal edges by
viewing it from top to bottom. The caliper is then placed
parallel to the occlusal plane while its 9 tips are aligned
with the anatomical contact points of two adjacent teeth.15
CLINICAL MANIFESTATION
Malocclusion is a condition that is characterized by
dental and skeletal components, generally related to poor
position and various local and systemic factors that can
cause problems in chewing, pronunciation, swallowing,
aesthetics, dental caries, impaired facial growth and
therefore a lower quality of life (Figure 2).17 In temporary
teeth, crowding may be a tendency due to the deficiency
of diastemas, primate space, existence of habits and other
anomalies that worsen in permanent teeth. Severity of
crowding can be related to poor oral hygiene, gingivitis,
periodontal disease, dental cavities, tooth mobility, and
tooth loss. These conditions cause functional, emotional
and social conditions in the individual.18 If crowding is
related to poor dental position, it can be treated with
dental movements, which can take multiple phases.
Generally, in orthopedic phase, which consists of
expansion if patient's conditions warrant it and they are a
candidate; with maxillary expansion and an orthodontic
phase through alignment, leveling and detailing with
brackets (Figure 3). An excellent treatment option in
patients with severe crowding and bilateral posterior
crossbite is rapid expansion of the maxilla, this in cases
where correction cannot be achieved through
interproximal smoothing and dental proclination, due to
degree of dental crowding. 19
Figure 2 (A-F): A 30-year-old female patient comes to the clinic due to recurrent canker sores in the vestibular fold
of labial mucosa. Upon complete analysis, the central incisor is found to have ectopic eruption and the canine
erupting around the central incisor. She presents reconstructions in the permanent and temporary lateral incisor,
the patient is asked to perform the extractions of 21 and 62, to later give the morphology to canine as central and to
lateral incisor.
Figure 3 (A-F): Nine-year-old female patient presents mixed dentition. Radiographic examination shows lack of
space for the eruption of permanent teeth. We wait for the root formation of the first molars to begin distalization
and expansion of the maxilla with Pendex and in the mandible with lip bumper. Initial orthopantomography,
orthopantomography during distalization, placement of Pendex, sixth activation appointment to pendex, placement
of lip bumper fixed with ligature and sixth activation appointment, the patient now presents class I molar.
Portillo FRL et al. Int J Res Med Sci. 2024 Apr;12(4):1344-1348
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As the spaces are limited, it is important to compensate
for the discrepancy between the sizes of the temporary
and permanent dentition. These spaces can be subdivided
into:
Primate space
They are located between the lateral incisors and the
canines of the upper arch and between the first molars
and canines of the lower arch.20
Development space
It is located between the upper and lower incisors. It is
related to the change in the dimensions of the arch and
going from a temporary to a permanent dentition,
together with the size of the arch and the width of the
permanent one, there is a need to generate spaces that are
approximately 2 mm per quadrant.21
Therefore, timely attention is important to perform
treatments (Figure 2) and avoid the inclusion of the
canine or the loss of permanent teeth (Figure 3). An
association has been found where maxillary canines are
impacted buccally with discrepancies in tooth size and
arch length.22-24 Padma Kumari and collaborators reported
a greater loss of space in patients where the primary
canines presented premature exfoliation compared to
control groups.25
Etiological factors have been identified with a positive
correlation with anteroinferior crowding and its
recurrences, such as the presence of lower third molars,
labial closure force, maximum lingual pressure, arch
dimension, tooth size, skeletal parameters.15 Although the
association between the presence of third molars and
dental crowding has not been fully established, there are
research groups and reports where an association has
been found. Dr. Palikarakia and collaborators in their
research report that the lower third molars can generate
mesial pressure that moves the lower posterior teeth
forward, causing the mandibular anterior tooth to suffer
from crowding, present in adolescent and young adult
patients in a range of ages. from 13 to 26 years during the
time of eruption of the third molars, however other
authors affirm that this pressure is not capable of showing
crowding, which is why they evaluated patients after
receiving orthodontic treatment and with the extraction of
the lower third molars, the degree of lower anterior dental
crowding is greater in patients with the presence of
mandibular third molars, as well as post-orthodontic
patients with third molars presented a shorter arch
length.26
If crowding is caused by poor positioning of the teeth, it
can be treated with a movement of the teeth, although
there is a possibility that extraction of the teeth will be
necessary to allow enough space when all the dental
organs cannot be properly aligned. in the basal arch. It is
essential to evaluate with individualized protocols and
decide the best therapeutic option, especially in those
patients who are candidates for tooth extractions since
this is irreversible and in the case of using orthodontics it
can prolong the treatment. Therefore, determining the
severity of dental crowding and the decision to perform
an orthodontic extraction are essential factors to plan
orthodontic treatment in terms of time and manage
irreversibility.27
CONCLUSION
Timely treatment of dental crowding improves the quality
of life of patients in biological, functional and aesthetic
aspects. Treatment options include the orthopedic phase
and orthodontic phase in which the extraction of teeth
may or may not be necessary.
Funding: No funding sources
Conflict of interest: None declared
Ethical approval: Not required
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Cite this article as: Portillo FRL, Valenzuela JG,
Alcaraz VMR, Urias AEV, Pérez DDRM, Guerrero
FMM et al. Dental crowding: A review. Int J Res
Med Sci 2024;12:1344-8.