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Pavithra H Dave, Nivethigaa B, Mahesh Ramakrishnan. Association Between Tongue Thrusting Habit And Malocclusion: A Retrospective Study. Int J Dentistry Oral Sci. 2020;S5:02:0023:129-133..
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Special Issue on: Prosthodontics and Maxillofacial Prosthetics. OPEN ACCESS https://scidoc.org/IJDOS.php
Association Between Tongue Thrusting Habit And Malocclusion: A Retrospective Study
Research Article
Pavithra H Dave1, Nivethigaa B2*, Mahesh Ramakrishnan3
1 Saveetha Dental College And Hospitals, Saveetha Institute Of Medical and Technical Sciences, Saveetha University, Chennai, 600050, India.
2 Senior Lecturer, Department of Orthodontics, Saveetha Dental College and Hospitals, Saveetha Institute Of Medical And Technical Sciences, Saveetha
University, Chennai, India.
3 Reader, Department of Pedodontics and Preventive Dentistry, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical
Sciences (SIMATS), Saveetha University, Chennai -77, India.
International Journal of Dentistry and Oral Science (IJDOS)
ISSN: 2377-8075
*Corresponding Author:
Nivethigaa B,
Senior Lecturer, Department of Orthodontics, Saveetha Dental College and Hospitals, Saveetha Institute Of Medical And Technical Sciences, Saveetha University, Chennai, India.
Tel: +91 9791972324
E-mail: nivethigaab.sdc@saveetha.com
Received: July 26, 2020
Accepted: August 20, 2020
Published: August 30, 2020
Citation: Pavithra H Dave, Nivethigaa B, Mahesh Ramakrishnan. Association Between Tongue Thrusting Habit And Malocclusion: A Retrospective Study. Int J Dentistry Oral Sci.
2020;S5:02:0023:129-133.
Copyright: Nivethigaa B©2020. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribu-
tion and reproduction in any medium, provided the original author and source are credited.
Introduction
A number of epidemiological studies on malocclusion and or-
thodontic treatment need have been performed worldwide which
have reported wide variations in the incidence of malocclusion.
The lack of suitable universal methods for recording and grad-
ing malocclusion and the different criteria used to dene maloc-
clusion have been a considerable factor that has inuenced such
extreme of variation [14, 29].
Development of malocclusion is determined by a combination
of genetic and environmental inuences. In recent years, the etio-
logical importance of genetic factors has been reduced, consider-
ing that many malocclusions recognize a post-natal origin [21].
Oral habits, particularly if they continue beyond the preschool
age, have been associated as an essential environmental determi-
nant correlated with the development of malocclusion [14]. The
role of continued digital sucking habit on the progress of maloc-
clusion has been reviewed by many researchers. Furthermore the
effect of abnormal swallowing patterns has been notably docu-
mented in the literature [30, 32].
Malocclusion has a tremendous physical, social and psychologi-
cal inuence on people and society; consequently, epidemiologi-
cal studies are vital to achieving comprehensive data for building
public health strategies for orthodontic prevention [17]. During
the last three decades, a striking increment in orthodontic therapy
demand has occurred as a result of the high understanding rate of
malocclusions, along with greater application to aesthetics. Many
Abstract
Background: Oral habits, particularly if they continue beyond the preschool age, have been associated as an essential environ-
mental determinant correlated with the development of malocclusion. Tongue thrusting habit is a state in which the tongue comes
between with any teeth when swallowing. The knowledge of prevalence and etiology of malocclusion can help form strategies for
prevention, interception, and corrective treatment. The study aimed to assess the prevalence of tongue thrusting and malocclusion
and to nd, if any correlation exists between the presence of tongue thrusting oral habits and the malocclusion status.
Materials and Method: This study association between tongue thrust and malocclusion, was done at a private dental college and
hospital. The cast sheets of patients were obtained from the patient record system. The data of each patient was obtained and
tabulated.
Results: In this study, we infer that there is a signicant association between tongue thrusting habit and malocclusion, in which
open bite was found to be the most commonly seen malocclusion with a p value of 0.001 done using Chi square test.
Conclusion: There was a high predominance of malocclusion in patients with tongue thrusting habits, in which open bite was
found to be the most commonly seen malocclusion. Other signicant malocclusion included crowding, spacing and proclination
in some cases. Hence adequate care should be taken from the younger age to stop the parafunctional oral habits from resulting
into a severe malocclusion.
Keywords: Incidence; Malocclusion; Oral Habits; Tongue Thrusting.
Pavithra H Dave, Nivethigaa B, Mahesh Ramakrishnan. Association Between Tongue Thrusting Habit And Malocclusion: A Retrospective Study. Int J Dentistry Oral Sci. 2020;S5:02:0023:129-133..
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studies have been published on the prevalence of malocclusion
and the need for orthodontic treatment in different ethnic groups.
Oral habits like nger and thumb sucking, lip sucking, mouth
breathing, nail-biting and so on can happen transitorily; however,
these habits, when extreme or maintained, can lead to poor den-
tal well-being or malocclusion. A study the prevalence of maloc-
clusions, oral habits and the need for orthodontic treatment in a
sample of 7- to 15-year-old Albanese schoolchildren and stated
that oral habits were present in 80.6% of their subjects [16]. A
previous study done in 2008 also conrmed that there was a posi-
tive association between deleterious oral habits and malocclusion.
However, Luzzi et al. in 2011 reported that no statistically sig-
nicant associations could be detected between the non-nutritive
sucking habits and malocclusion [3].
The tongue plays an essential role in respiration, mastication, de-
glutition, and speech. In normal deglutition, the tip of the tongue
rests on the lingual part of the maxillary anterior dentoalveolar
area; the teeth come in temporary contact and there is a least con-
traction of the perioral muscles, is least during deglutition, during
swallowing, and there is neither a tongue thrust nor a constant
forward posture. Tongue thrusting is a potent swallowing pattern
in infants. By age 2-4 years, functionally mature swallows emerge
[11].
Tongue thrusting habit is a condition in which the tongue makes
contact with any teeth anterior to the molars during swallowing
[23]. Most frequent signs of tongue thrusting are said to be for-
ward tongue posture and tongue thrusting during swallowing,
contraction of the perioral muscles, excessive buccinator hyper-
activity, and swallowing without the momentary tooth contact
normally required.
The knowledge of the prevalence and resultant malocclusion can
help form strategies for prevention, interception, and corrective
treatment. Given scal restraints due to high expenses of ortho-
dontic services and lack of publicly nanced dental treatment
plans in developing countries, such as India, it becomes more im-
portant to understand orthodontic treatment demand according
to the severity and to recognize modiable factors that can be
targeted by preventive and interceptive orthodontics.
Previously our team had conducted numerous studies which in-
clude clinical trials [31, 27, 15, 33, 34, 7, 26, 12, 22, 25, 9, 5, 8], in
vitro studies [13] and case reports [6] and hence the present study
was designed, to assess and quantify the prevalence of tongue
thrusting and malocclusion and to nd, if any correlation exists
between the presence of tongue thrusting oral habits and the mal-
occlusion status.
Materials and Methods
The present retrospective study was carried out in the Depart-
ment of Orthodontics of Saveetha Dental College and Hospital,
Chennai, Tamil Nadu. The study was of university setting and
carried out using data collected from patient records from June
2019-April 2020. The advantage of using a university setting is
that data is readily available and patients are of similar ethnicity.
The disadvantage of this type of setting is that it covers a specic
geographic area and trends in other locations are not assessed.
Ethical approval was obtained from the institution. The data was
reviewed by 2 reviewers. Case verication was done by 2 review-
ers. Non probability sampling of the available data was done. The
sample size consisted of 500 patients who had tongue thrusting
habits. Inclusion criteria included all the patients who had tongue
thrusting habits.
Data collection was carried out using dental details obtained from
the patient records. Data verication was carried out. The data
was tabulated using Microsoft Excel. Censored or incomplete
data was excluded from the study.
Statistical Analysis
The data was imported to SPSS software developed by IBM for
statistical analysis. Frequency, percentage of parameters was em-
ployed in the analysis. Chi square test was used to detect the sig-
nicance between gender, age, habit, and malocclusion. p value
less than to 0.05 was considered statistically signicant.
Result And Discussion
In our study, we conclude that there was a signicant association
between tongue thrusting habit and malocclusion, in which open
bite was found to be the most commonly seen malocclusion- p –
value 0.001< 0.05 [Chi square test]
Figure 1 shows the age distribution, in which 63% belonged to the
age group of less than 20 years, 28 % in the age group 21 to 40
years and 9 % in the age group 41 to 60 years.
Figure 2 shows the gender distribution, 52 % male population and
48 % female population.
Figure 3 shows the association between age and malocclusion,
less than 20 years had proclination 76 %, 21 to 40 years had open
bite of 72 % and 41 to 60 years had crowding 21 %. Thus from
graph 3 we infer that open bite is highly prevalent in the 21 to 40
years age group.
Figure 4 shows association between gender and malocclusion in
which the female population 37% had open bite and male popula-
tion 60 % had open bite. Thus from graph 4 we infer that open
bite is the highly prevalent malocclusion in the male population
than in the female population.
Malocclusion is established close to its full expression in an indi-
vidual with the eruption of all permanent teeth, thereby young
adolescents at the late mixed dentition and early permanent denti-
tion stage provide a much clearer prevalence of malocclusion and
orthodontic treatment needs than younger children. The study
by Giugliano et determined the prevalence of malocclusion, or-
thodontic treatment need, and the relationship of malocclusion
with associated factors, such as deleterious oral habits, in a North
Indian school going population of 12 and 15-year-old children in
Shimla city [10].
Results of the regression models revealed that mouth breathing
and thumb-sucking habits had a signicant impact on malocclu-
sion, signicantly affecting the presence of crowding and irregu-
larities in anterior segments, and increased maxillary overjet. Also,
tongue thrusters signicantly developed a reverse overjet, spacing
Pavithra H Dave, Nivethigaa B, Mahesh Ramakrishnan. Association Between Tongue Thrusting Habit And Malocclusion: A Retrospective Study. Int J Dentistry Oral Sci. 2020;S5:02:0023:129-133..
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in incisal segments, and anterior open-bite. Abundant reports in
the literature have stated that malocclusion in relation to these
traits is observed with a higher prevalence amongst those with
habits than without. Shetty et al found that when tongue thrust-
ing, mouth breathing, and thumb sucking were taken into con-
sideration, about 28.95% had malocclusion with a higher preva-
lence in relation to anterior maxillary protrusion [28]. Melson et
al, stated that both tongue-thrust swallow and teeth apart swallow
favor development of disto-occlusion, extreme maxillary overjet,
and open bite [20].
Oral habits like mouth breathing, abnormal swallowing, thumb
sucking, lip sucking, and nail-biting can have a primary inuence
on the essence of life and can affect the stomatognathic system
Figure 1. Age distribution in patients with tongue thrusting habits. Of the overall 500 patients, pink colour denotes patients
in the age group of less than 20 years is 63%, black colour denotes patients in age group 21-40 years is 28% and brown
denotes patients in age group 41-60 years is 9%. The presence of tongue thrusting was seen to be increased in the younger
age groups, indicating the need for strict measures to avoid the habit to prevent the occurrence of severe dental deformity.
Figure 2. Gender distribution in patients with tongue thrusting habits. Of the overall 500 patients, grey colour denotes the
male population of the study is 51.60% and purple colour denotes the female population of the study is 48.40%. The gender
distribution in the prevalence of malocclusion showed comparative increase in the male population.
Figure 3. The graph represents the association between age and malocclusion in patients with tongue thrusting habits.
Blue denotes open bite, red denotes proclination, green denotes spacing, orange denotes cross bite and yellow denotes
crowding. X axis represents the age distribution and the Y axis represents the number of patients with malocclusion. In the
age group of less than 20 years, cross bite was the most common and open bite was the least occurring malocclusion. In the
age group 21-40 years, open bite was the most and cross bite was the least occurring malocclusion and in the age group of
41-60 years, crowding was the most and cross bite was the least occurring malocclusion. (Pearson Chi-Square value-181.516
, p value-0.001 , <0.05) Chi- square test was used p<0.001, association between the two parameters age group and type of
malocclusion were statistically signicant.
Pavithra H Dave, Nivethigaa B, Mahesh Ramakrishnan. Association Between Tongue Thrusting Habit And Malocclusion: A Retrospective Study. Int J Dentistry Oral Sci. 2020;S5:02:0023:129-133..
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of the body [1]. This study showed that notable relationships ex-
isted between harmful oral habits and malocclusions. In a similar
study, evaluated the relationship between arch width and certain
oral habits in 3 to 6-year-old children and found that a model hab-
it leads to a decrease in maxillary arch width and mouth breathing
causes a decrease in the size of both arches [2].
An association exists amidst the etiology of an anterior open bite,
harmful oral habits, and a few orofacial defects. A connection
between the history of deleterious habits and the existence of
lingual interposition when swallowing, and with speech distur-
bances were recognized. These results highlight the signicant
interplay between orthodontists and speech-language patholo-
gists throughout the treatment of patients. The recovery role of
speech-language therapy stands out, through the oral myofunc-
tional therapy, indicating the positioning of the tongue during
swallowing, speech and when in habitual position [10, 4].
In a previous study, it was observed that tongue thrusting is the
most common oral habit constituting 29.5%. It can be dened
because tongue tip function during swallowing is directly related
to the variations in the contiguous anterior dentoskeletal circum-
stances. The changing patterns of tongue tip movement seem to
describe a functional adaptation to the variations in the arrange-
ment of the anterior malocclusion. Reasonably this functional
adaptation describes an effort to obtain an anterior oral seal dur-
ing swallowing and benet to the difference in the anterior oral
environment [19].
Thus, an alteration to an existing environment may yet be another
expression for the possible predominance of tongue thrusting in
young age groups. Several critics have noted that the intermo-
lar distance was statistically shorter in mouth-breathing subjects
while contrasted with that of nasal breathers, which symbolizes
a larger narrowing of the maxillary arch in the second molar area
[18, 24].
Conclusion
Within the limitations of the study, there was a high predomi-
nance of malocclusion in patients with tongue thrusting habits, in
which open bite was found to be the most commonly seen maloc-
clusion. Other signicant malocclusion included crowding, spac-
ing, and proclination in some cases. Hence adequate care should
be taken from a younger age to stop the parafunctional oral habits
from resulting in a severe malocclusion that would involve more
cost as well time for its correction when it persists in adulthood.
Author’s Contribution
First author (Pavithra H Dave) performed the analysis, interpre-
tation and wrote the manuscript. Second author (Dr.Nivethigaa
B.) contributed to conception, data design, analysis, interpretation
and critically revised the manuscript. Third author (Dr.Mahesh)
participated in the study and revised the manuscript. All the three
authors have discussed the results and contributed to the nal
manuscript.
Acknowledgement
The authors are thankful to Saveetha Dental College for provid-
ing permission to access the database and for giving a platform to
express our knowledge.
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