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Article abstract of DOI:10.1016/j.jallcom.2020.156762

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Full text of DOI:10.1016/j.jallcom.2020.156762

J Pediatr (Rio J). 2018;94(2):123---130
www.jped.com.br
ORIGINAL ARTICLE
Breathing mode influence on craniofacial development
and head postureଝ
Annel Chambi-Rocha∗, Ma Eugenia Cabrera-Domínguez, Antonia Domínguez-Reyes
Universidad de Sevilla, Facultad de Odontología, Seville, Spain
Received 6 January 2017; accepted 6 April 2017
Available online 14 August 2017
Abstract
KEYWORDS
Objective: The incidence of abnormal breathing and its consequences on craniofacial devel-
Breathing;
opment is increasing, and is not limited to children with adenoid faces. The objective of this
Craniofacial
study was to evaluate the cephalometric differences in craniofacial structures and head posture
development;
between nasal breathing and oral breathing children and teenagers with a normal facial growth
Head posture;
pattern.
Children
Method: Ninety-eight 7---16 year-old patients with a normal facial growth pattern were clinically
and radiographically evaluated. They were classified as either nasal breathing or oral breathing
patients according to the predominant mode of breathing through clinical and historical eval-
uation, and breathing respiratory rate predomination as quantified by an airflow sensor. They
were divided in two age groups (G1: 7---9) (G2: 10---16) to account for normal age-related facial
growth.
Results: Oral breathing children (8.0 0.7 years) showed less nasopharyngeal cross-sectional
dimension (MPP) (p = 0.030), whereas other structures were similar to their nasal breathing
counterparts (7.6 0.9 years). However, oral breathing teenagers (12.3 2.0 years) exhibited
a greater palate length (ANS-PNS) (p = 0.049), a higher vertical dimension in the lower ante-
rior face (Xi-ANS-Pm) (p = 0.015), and a lower position of the hyoid bone with respect to the
mandibular plane (H-MP) (p = 0.017) than their nasal breathing counterparts (12.5 1.9 years).
No statistically significant differences were found in head posture.
Conclusion: Even in individuals with a normal facial growth pattern, when compared with nasal
breathing individuals, oral breathing children present differences in airway dimensions. Among
adolescents, these dissimilarities include structures in the facial development and hyoid bone
position.
© 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. This is an open
access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/
4.0/).
ଝ
Please cite this article as: Chambi-Rocha A, Cabrera-Domínguez ME, Domínguez-Reyes A. Breathing mode influence on craniofacial
development and head posture. J Pediatr (Rio J). 2018;94:123---130.
∗
Corresponding author.
E-mails: anncharoc@alum.us.es, annel2302@gmail.com (A. Chambi-Rocha).
https://doi.org/10.1016/j.jped.2017.05.007
0021-7557/© 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND
license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

124
Chambi-Rocha A et al.
Influência do modo de respira¸cão sobre o desenvolvimento craniofacial a e postura
da cabe¸ca
PALAVRAS-CHAVE
Respira¸cão;
Desenvolvimento
craniofacial;
Postura da cabe¸ca;
Crian¸cas
Resumo
Objetivo: A incidência da respira¸cão anormal e de suas consequências no desenvolvimento
craniofacial aumenta e não é limitada a crian¸cas com fácies adenoideanas. O objetivo deste
estudo foi avaliar as diferen¸cas cefalométricas nas estruturas craniofaciais e na postura da
cabe¸ca entre crian¸cas e adolescentes com respira¸cão nasal e respira¸cão bucal com padrão de
crescimento facial normal.
Método: 98 pacientes com idades entre 7-16 anos com padrão de crescimento facial normal
foram avaliados de forma clínica e radiológica. Eles foram classificados como pacientes com
respira¸cão nasal ou respira¸cão bucal de acordo com a predominância do modo de respira¸cão por
meio da avalia¸cão clínica e histórica e da predominância da frequência respiratória conforme
qualificado por um sensor de fluxo de ar. Os pacientes foram divididos em duas faixas etárias
(G1: 7 a 9) (G2: 10 a 16) para contabilizar o crescimento normal facial relacionado à idade.
Resultados: As crian¸cas com respira¸cão bucal (8,0 0,7 anos de idade) mostraram menor
dimensão transversal nasofaríngea (MPP) (p = 0,030), ao passo que outras estruturas foram
semelhantes a seus pares com respira¸cão nasal (7,6 0,9 anos de idade). Contudo, os ado-
lescentes com respira¸cão bucal (12,3 2,0 anos de idade) mostraram maior comprimento do
palato (espinha nasal anterior-espinha nasal posterior (ENA-ENP)) (p = 0,049), maior dimensão
vertical na menor face anterior (Xi-ENA-Pm) (p = 0,015) e menor posi¸cão do osso hioide a respeito
do plano mandibular (H-PM) (p = 0,017) que seus pares com respira¸cão nasal (12,5 1,9 anos de
idade). Não foram constatadas diferen¸cas estatisticamente significativas na postura da cabe¸ca.
Conclusão: Mesmo em indivíduos com padrão de crescimento facial normal, em compara¸cão a
indivíduos com respira¸cão nasal, as crian¸cas com respira¸cão bucal apresentam diferen¸cas nas
dimensões das vias aéreas. Entre os adolescentes, essas dissimilaridades incluem estruturas no
desenvolvimento facial e na posi¸cão do osso hioide.
© 2017 Sociedade Brasileira de Pediatria. Publicado por Elsevier Editora Ltda. Este e´ um artigo
Open Access sob uma licen¸ca CC BY-NC-ND (http://creativecommons.org/licenses/by-nc-nd/4.
0/).
and/or posterior crossbites, class II malocclusion,11 con-
stricted palates, and gummy smiles resulting in unattractive
Introduction
facial features.5 In addition, OB children often suffer from
chronic gingivitis, periodontitis, candida infections,12 den-
tal erosion, and cavities.13 Due to the difficulty of breathing
and chewing simultaneously for extended periods, masti-
catory efficiency decreases.14 This, in turn, leads to OB
children’s preference for soft and oftentimes non-nutritious
foods that increase the possibility of malocclusions and
cavities.
Published evidence is inconclusive, in part, because
growth patterns have not been taken into account, as cer-
tain physical characteristics are shared by subjects with a
predominant vertical growth pattern, who, in turn, are more
likely to be OB children.15 In addition, decreased adenoids
and occlusal maturation have not been used as classification
parameters when comparing across subjects.8 Moreover, dif-
ferent diagnostic tools have been used to classify breathing
modes.
The main objective of this research was to evaluate the
cephalometric differences in craniofacial structures (i.e.,
the form and position of the maxilla, mandible, upper air-
way, and hyoid bone) and head posture between NB and OB
children and teenagers with a normal facial growth pattern,
using a measurable diagnostic tool for breathing mode and a
rigorous selection criteria of patients. It is hypothesized that
there are anatomic differences in craniofacial structures in
Physiological breathing is often affected by anatomic or
functional problems, causing the respiratory cycle to be
initiated not only through the nose but also through the
mouth.1,2 Compared to nasal breathing (NB) children, oral
breathing (OB) children are at higher risk for restless sleep,
diaphoresis and enuresis at night, and, in some cases, even
sleep apnea syndrome. The low-quality sleep materializes
as daytime sleepiness, irritability, and headaches3 likely to
negatively impact academic performance. Further, the pres-
ence of hyponasal speech or speech alterations4 increases
the likelihood of being classified with a learning disability.
In fact, many of these children are misdiagnosed with atten-
tion deficit hyperactivity disorder (ADHD) and sometimes
erroneously medicated.5
Several studies postulate that OB children exhibit char-
acteristics of the typical adenoid facies: a decrease in the
facial prognathism, a small nose and nostrils, a short upper
lip, and an open mouth posture which may be the source
for a backward and downward rotation of the mandible that
causes an increase in the vertical development of the lower
anterior face and a narrower anteroposterior upper airway
dimension.1,6---8 These patients’ muscle imbalance, owing to
an anatomic recondition, may lead to cranio-cervical hyper-
extension and kyphotic posture.9,10 There are also reports of
different types of malocclusion, such as open bites, anterior

Breathing mode influence on craniofacial development
125
OB compared to NB children and teenagers, even in patients
with a normal facial growth pattern.
nasal respiratory frequency (under 17 breaths per minute)
as measured by the staff and based on parental reports
that report predominant breathing through the mouth,
showing an open mouth posture during the day and/or
while sleeping (change from an upright to a supine position
may cause a change in respiratory mode).1 Moreover, if
the children frequently exhibited three or more of these
symptoms, they were included: snoring, wheezing, drooling
on the pillow, waking up during the night gasping for air,
or getting up tired in the morning. Children were classified
as nasal breathers if they had a high nasal respiratory
frequency (above 18 breaths per minute), a closed mouth
during the day and night, and the previously described
symptoms were absent. The classification was supported by
an otolaryngologist by means of rhinomanometry.
Lateral radiographs were taken standing with the body
relaxed and with a natural head position (self-balance
position)17 by X-ray equipment Planmeca Promax (Planmeca
Oy), at the Faculty of Dentistry of Seville University. The
cephalostat was placed without adding any pressure, so
as to not affect the child’s posture. Traditional cephalo-
metric landmarks were hand-traced and digital radiographs
were imported into a commercially available software sys-
tem (Ortho TP® , Vimercate MicroLab, Vimercate, Italy) and
analyzed again. The cephalometric parameters were chosen
based on previous publications6,17---19 (Figs. 1 and 2). How-
ever, new measurements were added for airway dimensions:
Method
Participants
Participants were recruited at random during a routine clinic
visit at the College of Integrated Child Dentistry at Seville
University. Inclusion criteria were as follows: white boys
and girls between 7 and 16 years of age; normal growth
pattern appearance; free of any neurologic or congenital
alterations, genetic syndromes, craniofacial malformations,
severe systemic disease, respiratory allergies, obstructive
sleep apnea syndrome (OSAS), or asthma. Exclusion criteria:
any upper airway surgery, orthodontic or orthopedic proce-
dures, prolonged use of a pacifier (more than six months)
and/or baby bottle (more than two years), any habits like
lip or finger sucking, or an evident anterior tongue posi-
tion. Of the 187 children (11.3 0.2 years, 58.3% girls and
41.7% boys) evaluated for eligibility, 98 met the inclusion
criteria. For all patients, one parent and/or legal guardian
signed the informed consent form. The study and its pro-
tocol were approved by the Research Ethics Committee of
the Virgen Macarena-Virgen del Rocio University Hospitals
(Seville, Spain).
Measures
• USP: Distance of a point of soft palate (5 mm under to
the upper point of the soft palate) (USP) to the horizontal
counterpoint on the posterior pharyngeal wall parallel to
the Frankfurt horizontal plane (FHP).
• IT: Distance of the posterior and inferior point of tonsil (T)
(5 mm upper to the down point of the tonsil) to horizontal
counterpoint on posterior pharyngeal wall parallel to the
FHP.
• MPP: Distance of the intersection points on anterior and
posterior pharyngeal wall of the middle of the USP and IT
parallel to the FHP.
• MPp: Distance of the intersection points on anterior and
posterior pharyngeal wall of the mandibular plane (MP)
parallel to the FHP.
Normal facial growth pattern was confirmed by cranial
and facial index and cephalometric parameters (FP-MP)
(n = 68◦ 3.5◦) to exclude children with a growth pattern
predisposition. The cranial index measures transverse and
anteroposterior diameters of the skull based on the follow-
ing formula: maximum transverse diameter × 100/maximum
anteroposterior diameter. The scores are categorized as
follows: dolichocephalic (<76), mesocephalic (76---81), or
brachycephalic (>81). The facial index measures vertical and
transverse parameters of the facies. The height of the face
is determined starting on the superciliar plane (the line unit-
ing the eyebrows) and measuring vertically to the gnathion
point (i.e., the lowest point of the soft chin). The width
of the face is measured based on the bizygomatic width as
follows: maximum vertical diameter × 100/maximum trans-
verse diameter. The scores classify facies as: brachyfacial
(<97), mesofacial (97---104), or dolichofacial (>104).16
• C3P: Distance between posterior pharyngeal from the
most anterior and inferior point on the corpus of the third
cervical vertebra (C3) and anterior pharyngeal (P) parallel
to the FHP.
Breathing mode (oral vs. nasal) was assessed by an
Airflow Sensor for e-Health Platform, designed by Cooking
Hacks (Libelium® , Libelium Comunicaciones Distribuidas
S.L, Zaragoza, Spain). The sensor measured the nasal
respiratory frequency accurately by detecting temperature
changes in the airflow. This device consists of a set of
two prongs placed in the nostrils and secured by a flexible
thread that fits behind the ears. Breathing is measured by
the sensors located inside the prongs. Two measurements
were taken at different times to avoid punctual substantial
fluctuations that could affect results. Patients underwent a
complete clinical examination, and their clinical history and
data were collected through a parent questionnaire. Based
on this information, participants were classified as either
OB or NB patients. OB children were defined by a lower
To detect errors in landmark identification and mea-
surements, twenty randomly selected lateral cephalometric
radiographs were measured and compared by the same
investigator two weeks later.
Finally, patients were divided into two age groups
(G1 = 7 --- 9 years) (7.8 0.5 years) and (G2 = 10---16 years)
(12.3 1.0 years) for three main reasons: (1) to avoid
confusing breathing mode influence on craniofacial devel-
opment with normal changes in growth; (2) to account for
the process of occlusal maturation----associated with changes
in the vertical dimension of the face----based on the variation
in the eruption of permanent teeth to replace mixed denti-
tion; and (3) to account for the decrease of adenoids that
starts between the ages of 7 and 10, which widens the dif-
ferences in nasopharyngeal dimensions. In children younger

126
Chambi-Rocha A et al.
S
N
S0
S
CTV-SN
13 14
OPT-SN
7
FhP
4
FC
Fhp
2
Ad2
2
6
8
PtV-Ad
11
Ad1
PNS
Ba
5
3
1
9
ANS
USP
4
A
Xi
PNS
MPP
FP
Pm
5
IT
Go
10
B
1
6
12
MP
Gn
P
H
7
C3P
Figure 1 Cephalometric landmarks, angles, and reference
planes. Growth pattern: 1. FP-MP Angle formed by facial plane
(N-Pg) and mandibular plane (Gn-Go). Facial plane is formed
by nasion (N) and pgonion (Pg). Mandibular plane is formed
by gnation (Gn) and gonion (Go); facial height: 2. FCNA Angle
formed by facial center point (FC) and line FC-nasion (N) and
line FC-subspinale (A); 3. Xi-ANS-Pm Angle formed by center of
the ramus point (Xi) and line Xi-anterior nasal spine (ANS) and
Xi-suprapogonion (Pm); Maxilla: 4. SNA Angle formed by skull
base line (SN) and line N-subspinale (A). Skull base is a plane
from sella (S) to nasion (N); 5. ANS-PNS Distance from anterior
nasal spine (ANS) to posterior nasal spine (PNS); 6. ANS-PNS-
FhP Angle formed by palatal plane (ANS-PNS) and Frankfurt
plane (FhP). Frankfurt plane is formed by orbitale (Or) and
ponion (Po); Mandible: 7. SNB Angle formed by skull base line
(SN) and line N-supramentale (B); 8. MP-FhP Angle formed by
mandibular plane (MP) and Frankfurt plane (FhP); 9. Go-FC Dis-
tance from gonion (Go) to the facial center (FC); 10. Xi-Pm
Distance from Xi to suprapogonion (Pm); Maxilla-Mandible: 11.
ANB Angle formed by subspinale (A) and nasion (N) line and line
N-supramentale (B); Hyoid bone: 12. H-MP Distance from the
most anterior and superior point of hyoid bone (H) perpendicular
to mandibular plane (MP); Craniocervical Posture: 13. OPT-SN
Angle formed by (SN) and odontoides (OPT). OPT is formed by
a line through the postero-superior point and postero-inferior
point of odontoides; 14. CVT-SN Angle formed by (SN) and cer-
vical (CVT). CVT is formed by a line through the postero-superior
point and postero-inferior point of the four cervical.
Figure 2 Airway dimensions. Nasopharynx: 1. Ad1-Ba Dis-
tance of (ad1) to basion (Ba); Ad1 is the intersection point of
posterior pharyngeal wall and the line from posterior nasal spine
(PNS) to basion (Ba); 2. ad2-S0 Distance of (ad2) to (S0). Ad2 is
the intersection point of posterior pharyngeal wall and the line
from the midpoint (S0) of the line from sella (S) to basion (Ba) to
posterior nasal spine (PNS); 3. PtV-Ad Distance of (PtV) point to
adenoid (Ad). PtV is a vertical line perpendicular to FhP passing
through the most posterior point of the fossa pterigomaxilar.
PtV point is located 5 mm upper to PNS. Oropharynx: 4. USP
Distance of a point of soft palate (5 mm under to the upper
point of Soft Palate) (USP) to the horizontal counterpoint on
the posterior pharyngeal wall parallel to Frankfurt Plane (FhP).
5. MPP Distance of the intersection points on anterior and pos-
terior pharyngeal wall of the middle of (USP) and (IT) parallel to
FhP. 6. IT Distance of the posterior and inferior point of tonsil
(T) (5 mm upper to the down point of the tonsil) to horizontal
counterpoint on posterior pharyngeal wall parallel to FhP. 7.
MPP Distance of the intersection points on anterior and poste-
rior pharyngeal wall of the mandibular plane (MP) parallel to
FhP; Hypopharynx: 8. C3P Distance between posterior pharyn-
geal since the most anterior and inferior point on the corpus of
the third cervical vertebra (C3) and anterior pharyngeal.
samples. Statistical significance was set at two-sided
p < 0.05. Bonferroni correction was used as the adjustment
method to maintain the probability of type I error below
5% (0.05). Accordingly, the p-value to consider statistically
significant differences was 0.05/22 = 0.002. Statistical tests
were performed using SPSS (SPSS for Windows, Version
16.0. Chicago, USA).
than 7 years old, adenoids are still physiologically present
in a considerable volume in NB and OB children; therefore,
it may difficult to find differences in the adenoids zone.20
Statistical analyses
Data were analyzed using descriptive statistical methods.
Quantitative variables were described with means and
standard deviations, and differences were tested for
significance with Student’s t-test for independent samples.
Differences in non-parametric variables were tested for
significance with the Mann---Whitney U test for independent
Results
The average respiratory rate was 18 breaths per minute;
the lowest respiratory rate detected was 12 breaths per

Breathing mode influence on craniofacial development
127
minute and the highest rate was 25 breaths per minute. The
average cranial and facial index scores were 79.3 2.4 and
101.5 1.7, respectively.
craniofacial hyperextension, differences were not statisti-
cally significant. It is speculated that the intense use of new
technological devices by the young, such as cell phones and
tablets, might contribute this lack of substantial differences
in craniofacial hyperextension.
Means and standard deviations for cephalometric
variables----craniofacial, hyoid position, head posture
(Table 1), and airway parameters (Table 2)----from 56 OB
patients (64.6%) and 42 NB patients (35.4%) were compared
by age group. According to the lateral cephalometric anal-
ysis, in G1 the airway distance in the region of the tonsils
(MPP) was lower in OB (8.0 0.7 years) than NB (7.6 0.9
years) (p = 0.03). No statistically significant differences in
the airway were found in G2. However, in G2, the lower
anterior facial height (Xi-ANS-Pm) and the palate length
(ANS-PNS) were higher in OB (12.3 2.0 years) than in NB
(12.5 1.9 years) (p = 0.015 and p = 0.049, respectively).
Also, the hyoid bone was located in a lower position
relative to the mandibular plane (H-MP) in OB teenagers
than NB ones (p = 0.017). Finally, no statistically significant
differences were found in the head posture between OB
and NB patients in either age group (Table 2).
A previous study found myofunctional and craniofacial
alterations among OB children between the ages of 7---10,23
whereas the present study found these alterations in OB
children with a mean age of 12.3 2.0 (G2). The discrep-
ancy may result from these studies failing to take the
growth patterns into account. In the present study, patients
with an abnormal growth pattern were excluded based on
the cranial and facial index and cephalometric parame-
ters, because patients with a vertical growth pattern have
common skeletal features, i.e., narrower anteroposterior
dimension of the airway, retrusion of the maxilla and the
mandible, vertical maxillary excess, and a higher class
II skeletal discrepancy.19,28 These patients’ characteristics
might be a compensatory mechanism that could trigger the
transition from NB to OB. Conversely, horizontal growth pat-
tern is usually characterized by a more anterior mandible.
This results in a wider lower pharyngeal airway, which favors
nasal breathing. Therefore, growth patterns could affect or
benefit physiological respiratory function.29
Discussion
Previous studies report that OB children have a hyperdi-
vergent facial pattern21---24 and a greater lower anterior
facial height6,11 that it was observed in our research in
OB teenagers (G2) with a normal facial pattern but not in
G1. A greater inclination of the mandible plane22,23 was
observed which, together with a posterior rotation of palatal
plane,25 might indicate the vertical direction of mandibu-
lar growth11,26 and the development of a class II skeletal
malocclusion.11 However, the OB patients (63.9%) presented
class I skeletal occlusion. According to previous findings,
OB patients’ maxilla and mandible were more retruded in
relation to their skull base.23 Nevertheless, Ucar et al.25
observed that only the maxilla was more retrognathic,
whereas others found that only the mandible was more
retruded.26
It is important to be able to detect patients with an
OB predomination. Early referral for the correction of this
pathological function is key for the prevention of irregulari-
ties in craniofacial development and orthodontic problems.
By eliminating the growth pattern confounding in this study
and comparing patients according to their growth stage, it
was possible to detect if real differences exist between NB
and OB children (G1) and teenagers (G2).
This study has certain limitations. First, in a cross-
sectional study, associations do not imply causal relation-
ships. In fact, Shanker et al.28 found that several children
switched between oral and nasal respiratory mode during
the four years of their investigation. However, as with any
treatable or preventable condition, the possibility of an
observational longitudinal study without intervening once
OB is detected is precluded for ethical reasons. Second, the
small sample size resulting from the strict selection criteria
may have limited the power of the analyses to detect fur-
ther differences. Third, because this study did not recruit
NB as OB participants, the power of the analyses may have
suffered from this substantial difference in the sizes of
the subgroups being compared. Despite these limitations,
these findings may help medical professionals better man-
age patients with breathing disturbances, knowing that this
might indicate a developmental imbalance.
The study also has its strengths. The highly precise selec-
tion criteria, by including only patients with normal growth
pattern, reduced the potential bias of including children
with a genetic predisposition for OB. In addition, occlusal
maturation and the physiological decrease of the adenoids
were taken into account when comparing the results. Finally,
a sensor that supplied measurable data to better classify
patients’ mode of breathing was utilized. To the best of
the authors’ knowledge, this measurement device had never
been used in this context. This combined with the fact that
a constant plane was used as reference for the airway mea-
surements, may prove these data to be more accurate than
those of much of previous research.
The present results show a low position of the hyoid bone
relative to the mandibular plane in OB in G2, which supports
previous findings by Cuccia et al.27
Nasopharyngeal sectional dimensions increase with the
rest of body tissues during the growth period, but the ade-
noid tissue starts to diminish between the ages of 7 and
10, only to disappear during adulthood. The measurements
of the upper airway space were smaller in OB than in NB
children (G1) in the region of the tonsils (MPP) but not in
G2, supporting previous work.26 Therefore, tonsils are more
hypertrophic in children than teenagers. This result could be
affected by the possibility that G1 patients’ adenoids were
still at the onset of their reduction, whereas G2 patients’
adenoids were already shrunken. In addition, the new air-
way measurements in this study could affect the ability to
compare, because they were parallel to the Frankfurt plane
(a constant plane) to avoid incorrect comparative results
based on a variable plane.
Several studies report OB patients with cranio-cervical
hyperextension,27 whereby postural problems are signifi-
cantly more common among these children.9 The present
research showed a cervical spine postural change in 90.3%
of OB but, as both groups presented high percentages of

Table 1 Craniofacial, hyoid position, and head posture parameters in nasal and oral breathing children and teenagers.
Group I
Group II
OB
NB
OB
67.028◦
p-Value
NB
p-Value
Growth pattern
1. FP-MP
66.813◦
1.13
3.38
0.864a
67.056◦
1.91
67.000 2.71◦
0.958a
Facial height
2. FCNA
3. Xi-ANS-Pm
58.438◦
44.250◦
1.87
3.47
57.639◦
43.917◦
4.48
3.93
0.635a
0.838a
57.833◦
42.278◦
2.76
3.30
59.962◦
46.346◦
3.05
3.69
0.111a
0.015a
Maxilla
4. SNA
5. ANS-PNS-FHP
6. ANS-PNS
79.438◦
3.38
3.13
81.750◦
4.57
3.85
0.214a
0.659a
0.733a
78.944◦
0.56◦
46.222 2.63 mm
2.57
3.98
77.115◦
4.63
2.82
0.298a
0.171a
0.049a
−1.750◦
−1.056◦
−2.000◦
44.125 3.90 mm
44.667 3.59 mm
49.269 3.75 mm
Mandible
7. SNB
8. MP-FHP
9. Go-FC
10. Xi-Pm
77.500◦
26.563◦
51.000 4.62 mm
4.50
2.61
77.353◦
26.000◦
50.528 4.11 mm
3.81
5.54
0.892a
0.788a
0.797a
0.81a
77.688◦
28.000◦
57.167 3.26 mm
63.833 mm 3.29 mm
2.65
4.19
74.250◦
28.192◦
58.077 mm 6.57 mm
63.769 mm 6.59 mm
3.18
3.73
0.082b
0.911a
0.706a
0.979a
58.875 mm 4.12 mm
56.722 mm 1.97 mm
Maxilla-mandible
11. ANB
2.063◦
2.88
4.250◦
2.49
0.60a
1.833◦
1.67
2.192◦
3.12
0.757a
Hyoid bone
12. H-MP
9.500 mm 1.61
7.765 3.73 mm
0.683b
8.563 3.58 mm
12.100 mm 6.06 mm
0.017b
Craniocervical posture
13. OPT-SN
14. CVT-SN
83.813◦
9.94
7.94
83.361◦
106.194◦
12.15
10.75
0.928a
0.941a
79.944◦
101.444◦
9.26
7.48
85.808◦
9.72
10.22
0.172a
0.11a
105.875◦
108.115◦
Bold values represent the statistically significant difference.
NB, nasal breathing; OB, oral breathing.
a
Student’s t-test.
Mann---Whitney U-test.
b

Breathing mode influence on craniofacial development
129
Table 2 Airway parameters in nasal and oral breathing children and teenagers.
Group I
Group II
OB
NB
OB
p-Value
NB
p-Value
Airway Nasopharynx
1. ad1-Ba
2. ad2-S0
3. PtV-Ad
23.833 5.57 mm
22.750 3.17 mm
11.500 3.76 mm
21.529 7.07 mm
21.417 3.41 mm
10.000 3.69 mm
0.261b
0.358a
0.724b
21.611 3.87 mm
21.625 4.07 mm
14.556 6.00 mm
22.192 5.54 mm
20.800 6.28 mm
13.692 4.99 mm
0.789a
0.647b
0.717a
Oropharynx
4. USP
5. MPP
6. IT
12.688 2.01 mm
11.000 2.46 mm
10.063 2.51 mm
10.500 2.34 mm
11.333 2.72 mm
8.765 2.15 mm
10.472 1.89 mm
9.972 2.69 mm
0.221a
0.030b
0.650a
0.637a
14.222 3.98 mm
10.000 2.34 mm
10.167 4.13 mm
9.056 2.81 mm
12.577 3.38 mm
9.346 2.60 mm
11.077 2.72 mm
10.731 3.94 mm
0.309a
0.554a
0.539a
0.287a
7. MPp
Hypopharynx
8. C3P
9.938 2.77 mm
9.86 3.63 mm
0.958a
8.444 3.14 mm
10.692 3.82 mm
0.162a
Bold value represents the statistically significant difference.
NB, nasal breathing; OB, oral breathing.
a
Student’s t-test.
Mann---Whitney U test.
b
After examining children and teenagers with a nor-
mal growth pattern, this study shows that there are
cephalometric differences between individuals with oral
breathing and nasal breathing modes. Compared to nasal
breathers, a lower anteroposterior dimension of the airway
in oral breathing children is found; whereas in teenage oral
breathers, there is a greater lower anterior facial height, a
longer palate, and a lower position of the hyoid bone relative
to the mandibular plane.
These findings are of practical interest to clinicians when
diagnosing, treating, and/or referring patients to specialists
for breathing disturbances-related issues. As these issues
might indicate a development imbalance, early diagnosis is
important to correct or ameliorate any negative effects with
timely treatment.
Future research examining larger samples of patients
with same selection criteria as used here is needed in order
to examine their craniofacial development according to
mode of breathing, while taking into account growth pat-
tern, age, and gender. Such a study may provide further
evidence of the substantial influence of breathing in cra-
niofacial development and head posture.
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Conflicts of interest
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2010;120:2089---93.
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