BREATHING AND THE INFLUENCE ON CHILDHOOD DEVELOPMENT:
Dr. Yosh Jefferson in a paper entitled Mouth breathing: adverse effects on facial growth, health, academics, and behavior states the following: “The vast majority of health care professionals are unaware of the negative impact of upper airway obstruction (mouth breathing) on normal facial growth and physiologic health. Children whose mouth breathing is untreated may develop long, narrow faces, narrow mouths, high palatal vaults, dental malocclusion, gummy smiles, and many other unattractive facial features”.
In this paper he also states: “These children do not sleep well at night due to obstructed airways; this lack of sleep can adversely affect their growth and academic performance. Many of these children are misdiagnosed with attention deficit disorder (ADD) and hyperactivity”.
“It is important for the entire health care community (including general and pediatric dentists) to screen and diagnose for mouth breathing in adults and in children as young as 5 years of age. If mouth breathing is treated early, its negative effect on facial and dental development and the medical and social problems associated with it can be reduced or averted”.
Jefferson Y. Mouth breathing: adverse effects on facial growth, health, academics, and behavior. Gen Dent. 2010 Jan-Feb;58(1):18-25; quiz 26-7, 79-80.
For information about upcoming Buteyko breathing courses for Children and their parents visit: https://buteykoclinic.com/courses/
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Group size is limited. Courses are for children aged 5 and older.
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Prevalence of Habitual Mouth Breathing in Children
Studies report that over 50% of children persistently breathe through an open mouth. This can cause disrupted sleep, adversely impact on academics, and negatively affect facial features and teeth. It is vitally important for children to breathe through their nose with their tongue resting in the roof of the mouth.
1. A 2012 paper published in the International Journal of Pediatrics investigating the long-term changes to facial structure caused by chronic mouth breathing noted that this seemingly ‘benign’ habit has in fact immediate and/or latent cascading effects on multiple “physiological and behavioural functions”. The paper even suggested that habitual mouth breathing may even be connected to sudden infant death syndrome. Trabalon M, Schaal B. It Takes a Mouth to Eat and a Nose to Breathe: Abnormal Oral Respiration Affects Neonates’ Oral Competence and Systemic Adaptation. International Journal of Pediatrics. 2012. (207605 ):10 pages
2. In a randomized sample of town’s population of 23,596 inhabitants, children were selected by lots according to a random number table until 370 had been enrolled; this number had been determined by statistical calculation. After clinical assessment had been carried out, researchers concluded that 55% of the children involved in the study were found to be mouth breathers.
J Pediatr (Rio J).2008 Sep-Oct;84(5):467-70.
3. In a separate study, mouth breathing prevalence in children was of 53.3%. There was no significant difference between gender, age and type of breathing. Furthermore, mouth breathing increased the risk of facial alterations including incomplete lip closure, fallen eyes, high palate, anterior open bite, hypotonic lips and circles under the eyes. Brazilian Journal of Otorhinolaryngology. Volume 72, Issue 3, May–June 2006, Pages 394–398
4. To identify the prevalence of mouth breathing in children at primary school ages from 6-9 years, researchers in Portugal examined 496 answered questionnaires from parents. It was found that 56.8% of children in this study breathed through their mouth.
Felcar Jm, Bueno Ir, Massan Ac, Torezan Rp, Cardoso Jr. Prevalence of mouth breathing in children from an elementary school. Cien Saude Colet.2010 Mar;15(2):437-44.
5. In another study involving 150 children in the sample with ages ranging from 8 to 10 years, two tests were carried out to determine whether a child was a mouth or a nose breather:
- test 1- breathe steam against a mirror
- test 2 – water remains in the mouth with lips closed for 3 minutes.
The results showed that mouth breathing prevalence was 53.3%. There was no significant difference between gender, age and type of breathing. Valdenice Aparecida De Menezesa, Rossana Barbosa Lealb, , Rebecca Souza Pessoac, Ruty Mara E. Silva Pontesd. Prevalence and factors related to mouth breathing in school children at the Santo Amaro project-Recife, 2005 Brazilian Journal of Otorhinolaryngology. Volume 72, Issue 3, May–June 2006, Pages 394–398
6. In a study to investigate the relationship between mouth breathing and atopic dermatitis, the prevalence of mouth breathing during the day and mouth breathing during sleep were 35.5% and 45.9%, respectively. There were significant associations between MBD and atopic dermatitis. Association between mouth breathing and atopic dermatitis in Japanese children 2–6 years Old: A Population-Based Cross-Sectional Study. Harutaka Yamaguchi et al. 27, 2015.
Mouth Breathing, Cognitive Effects and Reduced Academic Achievement
1. This study investigated how mouth breathing syndrome is very common among school-age children, and is possibly related to learning difficulties and low academic achievement. It examined this from the point of view of working memory, reading comprehension and arithmetic skills in children with nasal and mouth breathing.
This was an analytical cross-sectional study with a control group conducted in a public university hospital. 42 children (mean age = 8.7 years) who had been identified as mouth breathers were compared with a control group (mean age = 8.4 years) matched for age and schooling. All the participants underwent a clinical interview, tone audiometry, otorhinolaryngological evaluation and cognitive assessment of phonological working memory (numbers and pseudowords), reading comprehension and arithmetic skills.
RESULTS: Children with mouth breathing had poorer performance than controls, regarding reading comprehension, arithmetic and working memory for pseudowords, but not for numbers.
CONCLUSION: Children with mouth breathing have low academic achievement and poorer phonological working memory than controls. Teachers and healthcare professionals should be aware of the association of mouth breathing with children’s physical and cognitive health.
KUROISHI, Rita Cristina Sadako et al. Deficits in working memory, reading comprehension and arithmetic skills in children with mouth breathing syndrome: analytical cross-sectional study. Sao Paulo Med. J. [online]. 2015, vol.133, n.2, pp.78-83.
2. In recent decades, many studies on mouth breathing (MB) have been published; however, little is known about many aspects of this syndrome, including severity, impact on physical and academic performances. The objective of this study was to compare the physical performance in a six minutes walk test (6MWT) and the academic performance of MB and nasal-breathing (NB) children and adolescents.
The study included 156 children, 87 girls (60 NB and 27 MB) and 69 boys (44 NB and 25 MB). Variables were analyzed during the 6MWT: heart rate (HR), respiratory rate, oxygen saturation, distance walked in six minutes and modified Borg scale. All the variables studied were statistically different between groups NB and MB, with the exception of school performance and HR in 6MWT.
CONCLUSIONS: “Mouth breathing affects physical performance and not academic performance, we noticed a changed pattern in the 6MWT in the MB group. Since the MBs in our study were classified as non-severe, other studies comparing the academic performance variables and 6MWT are needed to better understand the process of physical and academic performances in MB children”.
Boas AP1, Marson FA, Ribeiro MA, Sakano E, Conti PB, Toro AD, Ribeiro JD. Walk test and school performance in mouth-breathing children. Braz J Otorhinolaryngol. 2013 Mar-Apr;79(2):212-8.
3. In this paper entitled A practical approach to allergic rhinitis and sleep disturbance management, Davies et al. comment that “sleep quality can be significantly impacted by nasal congestion (causing mouth breathing). This may lead to decreased learning ability, productivity at work or school, and a reduced quality of life.”
Davies MJ1, Fisher LH, Chegini S, Craig TJ. A practical approach to allergic rhinitis and sleep disturbance management. Allergy Asthma Proc. 2006 May-Jun;27(3):224-30.
4. In this paper Pediatric allergic rhinitis: physical and mental complications, Blaiss notes that allergic rhinitis has a far more negative impact on the health of the child than just a simple sneeze: “There are numerous complications that can lead to significant problems both physically and mentally in the child who suffers with allergic rhinitis. Under physical complications, recurrent and/or chronic sinusitis, asthma, and snoring impact children with AR. Sleep disturbances, poor school performance, and hyperactivity are all mental complications seen in many children related to their nasal allergies”.
Blaiss MS1. Pediatric allergic rhinitis: physical and mental complications. Allergy Asthma Proc. 2008 Jan-Feb;29(1)
5. The impact of the broad spectrum of sleep disordered breathing severity on cognition in childhood has not been well studied (mouth breathing in children is a significant contributor to sleep disordered breathing). This study investigated cognitive function in children with varying severities of SDB and control children with no history of SDB.
One hundred thirty-seven children (75 M) aged 7-12 were studied.
There was lower general intellectual ability in all children with SDB regardless of severity. Higher rates of impairment were also noted on measures of executive and academic functioning in children with SDB.
Findings suggest that neurocognitive deficits are common in children with SDB regardless of disease severity, highlighting that such difficulties may be present in children in the community who snore but are otherwise healthy; thus our results have important implications for the treatment of pediatric SDB.
Bourke R1, Anderson V, Yang JS, Jackman AR, Killedar A, Nixon GM, Davey MJ, Walker AM, Trinder J, Horne RS. Cognitive and academic functions are impaired in children with all severities of sleep-disordered breathing. Sleep Med. 2011 May;12(5):489-96.
6. Given the importance of studying the causes of learning disorders, this case-control study was designed to assess the nasal cavity volume, pharyngeal and palatine tonsils in children with and without learning disabilities.
48 children were submitted to ENT examination (history, physical examination) and specific tests (acoustic rhinometry, cavum radiography).
The results showed that students with learning disabilities have a higher prevalence of pharyngeal tonsil hypertrophy, and palatine tonsil hypertrophy: p < 0.001. The average volume of the nasal cavities showed no statistically significant association with learning difficulties.
This study concluded that children with adenotonsillar hypertrophy have more learning difficulties when compared to children without such hypertrophy.
Giovana Serrão Fensterseifer1 , Oswaldo Carpes2 , Luc Louis Maurice Weckx3 †, Viviane Feller Martha4 Mouth breathing in children with learning disorders. Braz. j. otorhinolaryngol. vol.79 no.5 São Paulo Sept./Oct. 2013
Habitual Mouth Breathing During Childhood Causes Crooked Teeth and Abnormal Development of the Face
A good-looking face is determined by a strong, sturdy chin, developed jaws, high cheekbones, good lips, correct nose size and straight teeth. When a face develops correctly, it follows that the teeth will be straight.
Straight teeth do not create a good-looking face, but a good-looking face will create straight teeth.
This section includes links to papers showing the relationship between mouth breathing during childhood and abnormal growth of the face.
If the mouth is hanging open, the tongue is not in the correct resting position. Instead the forces of gravity pull the face downwards. The jaws become narrow to cause overcrowding of teeth and become set back in the face to reduce the size of the upper airway. The result is increased risk of lifelong sleep disordered breathing including obstructive sleep apnoea, poor academic performance, behavioural issues and a less attractive face.
It is vitally important for good health and for the development of an attractive face, that parents of children understand the importance of nose breathing during childhood. Patrick McKeown of Buteyko Clinic International speaks of his own experience of 20 years of mouth breathing and how it contributed to sleepiness, difficulty in concentrating in school and craniofacial changes include a high upper palate, narrow maxilla, overcrowding of teeth. Since 2002, Patrick has taught the Buteyko Method to hundreds of children so that they understand the importance of nose breathing and have the tools to develop this habit.
Despite the evidence pointing to the importance of nose breathing during childhood, studies show that 50% of children continue to breathe through an open mouth. This can have devastating consequences on the health and quality of life of the child.
Here are some studies that demonstrate these findings:
1. In this study of 26 children, Kerr showed how development of the lower jaws began to normalise after the children switched from mouth to nasal breathing. This finding demonstrates that mouth breathing in childhood leads to craniofacial alterations in children.
Kerr WJ, McWilliam s JS, et al. Mandibular form and position related to changes mode of breathing – a five year longitudinal study. Angle Orthod 1987;59:91-96
2. The aim of the following study was “to analyze the variations of the size of the top jaw (maxilla) in children with prolonged mouth-breathing due to allergic rhinitis when compared with a control group with normal breathing pattern by using a three-dimensional analysis on digital casts”.
The study group consisted of 26 Caucasian children (19 females and 7 males) with average age 8.5 years. The study group was compared with a control group of 17 nasal breathing subjects.
Results showed that the dimension of the top jaw was significantly smaller in the group of mouth breathing children thus confirming the influence of mouth breathing on skeletal development with a significant constriction of the whole palate.
Lione R1, Buongiorno M1, Franchi L2, Cozza P1. Evaluation of maxillary arch dimensions and palatal morphology in mouth-breathing children by using digital dental casts. Int J Pediatr Otorhinolaryngol. 2014 Jan;78(1):91-5.
3. This study examined the ratio of bad habits, mouth breathing and crooked teeth as important issues in the prevention and early treatment of disorders linked to craniofacial growth. It posited that while bad habits can interfere with the position of the teeth and normal pattern of skeletal growth, obstruction of the nose, resulting in mouth breathing, can change the pattern of craniofacial growth causing crooked teeth. 3017 children were included in the study which aimed to examine if there was a significant correlation between bad habits/mouth breathing and malocclusion (crooked teeth).
The results showed that mouth breathing is associated with more severe crooked teeth (malocclusions).
Moreover, it found a significant association of mouth breathing with increased overjet and openbite, while no association was found with crossbite.
The study concludes that it is necessary to intervene early on these aetiological factors of malocclusion to prevent its development or worsening and, if already developed, correct it by early orthodontic treatment to promote eugnatic skeletal growth.
Grippaudo C1, Paolantonio EG1, Antonini G1, Saulle R2, La Torre G2, Deli R1. Association between oral habits, mouth breathing and malocclusion. Acta Otorhinolaryngol Ital. 2016 Oct;36(5):386-394.
4. In this study nasal-breathing impairment was examined as a possible determinant of maxillofacial development in children with adenoids/tonsils hypertrophy. The study group consisted of ninety-eight children with obligate mouth-breathing secondary to nasal septum deviation (group 1) and 98 age- and sex-matched nasalbreathing controls (group 2). Nasal-breathing function was assessed in all patients with clinical history, ENT instrumental examination and anterior active rhinomanometry.
CONCLUSION: Children with obligate mouth-breathing due to nasal septum deviations showed facial and dental anomalies in comparison to nose-breathing controls. Possible physiologic explanations of the findings are reported.
D’Ascanio L1, Lancione C, Pompa G, Rebuffini E, Mansi N, Manzini M. Craniofacial growth in children with nasal septum deviation: A cephalometric comparative study. International Journal of Pediatric Otorhinolaryngology 74 (2010) 1180–1183
5. In this study of 116 paediatric patients who had undergone orthodontic treatment, mouth breathers demonstrated considerable backward and downward rotation of the mandible, increased overjet (bucked teeth), increase in the mandible plane angle (longer face), a higher palatal plane (affects upper airways), and narrowing of both upper and lower arches at the level of canines and first molars compared to the nasal breathers group (overcrowding of teeth). The prevalence of a posterior cross bite was significantly more frequent in the mouth breathers group (49%) than nose breathers (26%)(P = .006). Abnormal lip-to-tongue anterior oral seal was significantly more frequent in the mouth breathers group (56%) than in the nose breathers group (30%).
Doron Harari DMD et al. 2010, The effect of mouth breathing versus nasal breathing on dentofacial and craniofacial development in orthodontic patients, The American Laryngological, Rhinological, and Otological Society, Inc. 2010 Oct;120(10)
6. This paper concludes that “children whose mouth breathing is untreated may develop long, narrow faces, narrow mouths, high palatal vaults, dental malocclusion (crooked teeth), gummy smiles and many other unattractive facial features.”
Jefferson Y, General dentist: Mouth breathing: adverse effects on facial growth, health, academics and behaviour. 2010 Jan- Feb; 58 (1): 18-25
7. This paper concludes that the switch from a nasal to an oronasal (mouth and nose combined) breathing pattern induces functional adaptations that include an increase in total anterior face height and vertical development of the lower anterior face.
Tourne, The long face syndrome and impairment of the nasopharyngeal airway, Angle Orthod 1990 Fall 60(3) 167- 76
8. This study finds that “long-standing nasal obstruction appears to affect craniofacial morphology during periods of rapid facial growth in genetically susceptible children with narrow facial pattern.” Furthermore, “the deleterious effects of nasal obstruction are virtually complete by puberty so the window of opportunity is relatively brief. Delay in intervention may result in unsuccessful orthodontic treatment which may require surgery at an older age.” It concludes that “effective orthodontic therapy may require the elimination of the nasal obstruction to allow for normalization of the facial musculature surrounding the dentition.”
Schreiner C (1996), Nasal air way obstruction in children and secondary dental deformities, UTMB, Dept. of Otolaryngology, Grand Rounds Presentation
9. In this study of 47 children between the ages of six to 15 years to determine the correlation between breathing mode and craniofacial morphology findings demonstrated that “a significant predominance of mouth breathing compared to nasal breathing in the vertical growth patterns studied. Results show a correlation between obstructed nasal breathing, large adenoids and vertical growth pattern”.
Baumam I, Plindert PK (1996) Effect of breathing mode and nose ventilation on growth of the facial bones, HNO 44(5): 229-34
10. This study demonstrates how the main characteristics of respiratory obstruction syndrome (blocked nose) are the presence of hypertrophied tonsils or adenoids, mouth breathing, open bite, cross bite, excessive anterior face height, incompetent lip posture, excessive appearance of maxillary anterior teeth, narrow external nares and V-shaped maxillary arch.
Lopatiene K, Babarsk as A (2002) Malocclusion and upper airway obstruction. Medicina 38(3): 277-283
11. This study of 73 children between the ages of three and six years concluded that “mouth breathing can influence craniofacial and occlusal development early in childhood”.
Mattar SE et al (2004) Skeletal and occlusal characteristics in mouth-breathing pre-school children. J Clin Pediatr Dent 28(4): 315-318
12. In his book Nutrition and Physical Degeneration, Dr. Weston makes this point about modernisation and mouth breathing: “His granddaughter had pinched nostrils and narrowed face. Her dental arches were deformed and her teeth crowded. She was a mouth breather. She had the typical expression of the result of modernisation after the parents had adopted the modern foods of commerce, and abandoned the oatcake, oatmeal porridge and sea foods”.
Dr Weston Price, Nutrition and Physical Degeneration. Price Pottenger Nutrition; 8th edition (January 31, 2008)
13. This study shows clinical and cephalometric data of 207 children who presented for evaluation of tonsil and/or adenoid problems were evaluated. Its findings report that a more open lip posture is associated with a more backwardly rotated face and larger lower facial height. Reduced sagittal airway size is associated with en bloc backward relocation of the maxilla and mandible.
Trotman CA, McNamara JA Jr, Dibbets JM, van der Weele LT. (1997) Association of lip posture and the dimensions of the tonsils and sagittal airway with facial morphology. The Angle Orthodontist 1997;67(6):425-32.
14. In a study involving monkeys who were forced to breathe through their mouths the experiments showed that the monkeys adapted to nasal obstruction in different ways. In general, the experimental animals maintained an open mouth. All experimental animals gradually acquired a facial appearance and dental occlusion different from those of the control animals. All the mouth breathing monkeys developed craniofacial changes and crooked teeth.
Ref: Egil P Harvold, Primate experiments on oral respiration. American Journal of orthodontics. Volume 79, issue 4, April 1981, pages 359- 372)
15. Following on from this study, Harvold also found that the mouth-breathing monkeys developed crooked teeth and other facial deformities, including “a lowering of the chin, a steeper mandibular plane angle, and an increase in the gonial angle as compared with the eight control animals”.
Tomer, Harvold Ep. Primate experiments on mandibular growth direction. Am J Orthod 1982 Aug: 82 (2): 114-9
16. This study was to examine if mouth breathing during childhood can alter muscular balance and lead to facial deformities. It sought to evaluate craniofacial developmental consequences originating from variations in breathing mechanisms in children who are nasal breathers or oral breathers, and those who have been tracheotomized.
The tracheotomized group was similar to the nasal group for greater activity of the masseter muscles than of the suprahyoid muscles during mastication, as well as in the measurements of facial, maxillary, and mandibular widths. The oral group showed reductions in each category. The tracheotomized group was similar to the oral group during maximum dental occlusion for significantly higher activity of the suprahyoid muscles compared with the masseter muscles, with reductions in vertical values.
The study found that a childhood tracheotomy might affect facial development in a way comparable with that of oral breathers, including abnormal facial growth variations.
Bakor SF1, Enlow DH, Pontes P, De Biase NG. Craniofacial growth variations in nasal-breathing, oral-breathing, and tracheotomized children. Am J Orthod Dentofacial Orthop. 2011 Oct;140(4):486-92.
Mouth Breathing and the Relationship to ADHD
Studies investigating the link between breathing and ADHD:
1. It is estimated that 30% of the western population suffer from rhinitis (congested or runny nose), and while not all children with rhinitis will develop ADHD, many with ADHD have rhinitis and treatment of such has therapeutic implications for ADHD.
Teaching a child to unblock their nose and breathe through it has no side effects, and in this vein should be the first step to addressing ADHD.
Children undergoing evaluation for ADHD should be systematically assessed for sleep disturbances because treatment of sleep disorders is often associated with improved symptomatology and decreased need for stimulants.
Domínguez-Ortega L1, de Vicente-Colomina A. [Attention deficit-hyperactivity disorder and sleep disorders]. Med Clin (Barc). 2006 Apr 8;126(13):500-6.
2. Brawley et al. analysed data from 30 children to determine the prevalence of allergic rhinitis in patients with physician diagnosed ADHD. The paper concluded that “most children with ADHD displayed symptoms and skin prick test results consistent with allergic rhinitis. Nasal obstruction and other symptoms of allergic rhinitis could explain some of the cognitive patterns observed in ADHD, which might result from sleep disturbance known to occur with allergic rhinitis”.
Brawley A1, Silverman B, Kearney S, Guanzon D, Owens M, Bennett H, Schneider A. Allergic rhinitis in children with attention-deficit/hyperactivity disorder. Ann Allergy Asthma Immunol. 2004 Jun;92(6):663-7.
3. In a study by Gottlieb et al., parent questionnaires from 3019 children were analysed to assess the prevalence of sleep-disordered breathing symptoms in five-year-old children and their relation to sleepiness and problem behaviours. Sleep-disordered breathing was defined as frequent or loud snoring, trouble breathing or loud, noisy breathing during sleep, or witnessed sleep apnea.
The study found parent-reported hyperactivity (19%) and inattention (18%) were common, with aggressiveness (12%) and daytime sleepiness (10%) reported somewhat less often. SDB symptoms were present in 744 (25%) children. The authors concluded that “children with sleep disordered breathing symptoms were significantly more likely to have parent-reported daytime sleepiness and problem behaviors, including hyperactivity, inattention, and aggressiveness.”
Gottlieb DJ1, Vezina RM, Chase C, Lesko SM, Heeren TC, Weese-Mayer DE, Auerbach SH, Corwin MJ. Symptoms of sleep-disordered breathing in 5-year-old children are associated with sleepiness and problem behaviors. Pediatrics. 2003 Oct;112(4):870-7.
4. This study examines ADHD and sleep disorders. Its findings show that around 25% of children with ADHD have some kind of sleep disorder but, unlike the case of adults, these often remain undetected. We nearly always choose to improve hyperactivity, attention deficit and impulsiveness symptomatically and forget to treat the associated sleep disorder.
It states that there is a clear correlation between ADHD and sleep disorders and they are very common in visits to the neuropaediatric department. Diagnosis of these patients is clinical. Neurophysiological evaluation, especially using polysomnography, provides objective confirmation of the symptoms. Novel treatments such as melatonin and other drugs are now available to improve the sleep pattern. By improving childrens’ sleep, the symptoms of ADHD are diminished and thus avoid the need to administer psychostimulants, which have undesirable side effects that produce a great deal of anxiety in the parents of these children.
Betancourt-Fursow de Jiménez YM1, Jiménez-León JC, Jiménez-Betancourt CS. Attention deficit hyperactivity disorder and sleep disorders. Rev Neurol. 2006 Feb 13;42 Suppl 2:S37-51.
Mouth Breathing Causes Sleep Disturbances in Children
Sleep disorder studies in Children
1. This paper states the following: “The good news is that sleep experts are becoming increasingly concerned about the impact of open mouth breathing during sleep, especially for children. Among these researchers is Dr. Christian Guilleminault, a leading figure in the field of sleep medicine. In the early 1970s, while working at the Stanford University Sleep Disorders Clinic, Dr. Guilleminault monitored the blood pressure of sleeping patients and discovered that when patients held their breath during sleep, their blood pressure dramatically increased”.
“Since then, Dr. Guilleminault has made many further discoveries in the field of sleep medicine. Among these, which I am delighted to include, is his recognition that: “the case against mouth breathing is growing, and given its negative consequences, we feel that restoration of the nasal breathing route as early as possible is critical.”
“These comments were published in a 2015 paper by Dr. Guilleminault which also states that “restoration of nasal breathing during wake and sleep may be the only valid ‘complete’ correction of paediatric sleep disordered breathing.”
Seo-Young Lee, Christian Guilleminault, Hsiao-Yean Chiu, Shannon S. Sullivan. Mouth breathing, “nasal disuse,” and pediatric sleep-disordered breathing. Sleep and Breathing December 2015, Volume 19, Issue 4, pp 1257–1264
2. This study sought to describe the prevalence, persistence, and characteristics associated with sleep disordered breathing (SDB) symptoms in a population-based cohort followed from 6 months to 6.75 years.
The results showed 12,447 children in ALSPAC with parental report of apnea, snoring, or mouth-breathing frequency on any one of 7 questionnaires. The prevalence of apnea (“Always”) is 1%-2% at all ages assessed. In contrast, snoring “Always” ranges from 3.6% to 7.7%, and snoring “Habitually” ranges from 9.6% to 21.2%, with a notable increase from 1.5- 2.5 years. At 6 years old, 25% are habitual mouth-breathers.
Bonuck KA1, Chervin RD, Cole TJ, Emond A, Henderson J, Xu L, Freeman K. Prevalence and persistence of sleep disordered breathing symptoms in young children: a 6-year population-based cohort study. Sleep. 2011 Jul 1;34(7):875-84.
3. This is a historical review on the discoveries of pediatric obstructive sleep apnea syndrome. The authors trace more than 50 years of questions and research. Their findings show that co-morbidities of sleep-disordered breathing are multiple, involving cognition, behavioral, and mood disorders, cardiovascular impairment, etc. There have been many advances in a short time due to the investigation of Obstructive Sleep Apnea Syndrome, but many questions still need responses.
Chien YH1, Guilleminault C2. Historical review on obstructive sleep apnea in children Arch Pediatr. 2016 Nov 28.
4. This is a study of how missing teeth in early childhood can result in abnormal development of the face with narrow upper airway. The potential association between missing teeth or early dental extractions and the presence of obstructive sleep apnea (OSA) was investigated. Results showed that 31 children with missing teeth (teeth agenises) and 11 children with early dental extractions had at least 2 permanent teeth missing. All children with missing teeth (n = 43) had clinical complaints and signs evoking OSA.
Guilleminault C, Abad VC, Chiu HY, Peters B, Quo S. Missing teeth and pediatric obstructive sleep apnea. Sleep Breath. 2016 May;20(2):561-8
5. In a paper published in the journal Pediatrics, researchers concluded that “inattention and hyperactivity among general pediatric patients are associated with increased daytime sleepiness and—especially in young boys—snoring and other symptoms of SDB. If sleepiness and SDB do influence daytime behavior, the current results suggest a major public health impact.
Chervin RD1, Archbold KH, Dillon JE, Panahi P, Pituch KJ, Dahl RE, Guilleminault C. Inattention, hyperactivity, and symptoms of sleep-disordered breathing. Pediatrics. 2002 Mar;109(3):449-56.
6. The obstructive sleep apnea syndrome (OSAS) is a respiratory disorder that occurs during sleep and it is relatively common in children. The goal of this study is to verify if there is a relationship between the obstructive sleep apnea syndrome (OSAS) and auditory processing.
The conclusion reached is that children with obstructive sleep apnea obtained worse results in auditory processing tests.
Ziliotto KN1, dos Santos MF, Monteiro VG, Pradella-Hallinan M, Moreira GA, Pereira LD, Weckx LL, Fujita RR, Pizarro GU. Auditory processing assessment in children with obstructive sleep apnea syndrome. Braz J Otorhinolaryngol. 2006 May-Jun;72(3):321-7
7. A link between the upper (nose) and lower airways (lungs) has been convincingly demonstrated both in health and disease. In this study, symptoms and signs from the upper airways were compared in children with asthma and in children without to find out more about this.
The study group included 27 asthmatic children, the control group 29 age and sex-matched healthy volunteers. Results showed that nasal blockage, mouth breathing, day time sleepiness, apnoeas, itching, sneezing, and hearing impairment were more prevalent in asthmatics compared with controls.
Steinsvåg SK1, Skadberg B, Bredesen K. Nasal symptoms and signs in children suffering from asthma. Int J Pediatr Otorhinolaryngol. 2007 Apr;71(4):615-21.
Tongue Tie and Mouth Breathing
Short notes taken by Patrick McKeown at the Bordeaux AOMT January 2016 Meeting. The speaker was Dr. Christian Guilleminault.
Patrick McKeown and Dr. Christian Guilleminault
The tongue of the newborn is very important for breast feeding. If the tongue is tied to the floor of the mouth by a short frenulum, then the baby may not be able to express milk from the mother. This will be very uncomfortable for the mother, and the baby may not receive proper nutrition. Additionally, breast feeding is vitally important for the new born baby as it causes manipulation of a number of muscles which are necessary for craniofacial growth (correct development of the face). While people often understand the importance of breast feeding for correct nutrition, less understood is the role of breast feeding in development of the face, jaws and airways of the child. Bottle feeding doesn’t encourage the child to move the jaws the same way.
When the tongue is tied, it is not able to move up into and rest in the roof of the mouth. Incorrect tongue posture leads to mouth breathing early during development. The position of the tongue is very important for fundamental elements to the growth of the child such as sucking and mastication (chewing).
If the child has some difficulties in speaking or doesn’t pronounce letters very well- we need to look under the tongue. This is very important as it indicates whether there is a problem in the craniofacial region.
The problem of tongue tie and mouth breathing should be recognised before orthodontics.
A lot of teenagers have sleep disordered breathing but this is identified much later. We should be looking at the child early on checking the size of their nostrils and whether they have a high narrow palate as this impacts the nasal fossa. This is also a family problem. It is important to examine the parents of the child. Of the children we looked at, 95% of the parents had same problem.
Also, the labial frenulum which is the top lip tie acts on the teeth and alveolar dental area.
If one breathes through the mouth, the face cannot grow in the proper way. We need to show that chronic breathing through the mouth has an impact on sleep disordered breathing. Breathing through the mouth also causes local inflammation- with measured inflammatory cytokines- this is going to have an abnormal reaction of adenoids and tonsils.
Sleep disordered breathing may not happen overnight. It is gradual. It can take years before the clinical syndrome can be recognised- maybe 2 years, 5 years or even 40 years.
Paper cited: Pediatric Obstructive Sleep Apnea and the Critical Role of Oral-Facial Growth: Evidences.
Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3551039/
Mouth Breathing and Changes to Body Posture Including Forward head Posture
1. Mouth breathing can affect the functions of the respiratory systems and quality of life. For this reason, children who grow up with this stimulus may have implications on physical and psychological aspects at adult age.
Conclusion reached in this paper: Childhood mouth-breathing yields consequences for the ventilatory function at adult age, with lower respiratory muscle strength and functional exercise capacity. Conversely, the quality of life was little affected by the mouth breathing in this study.
Jovana de Moura Milanesia , Priscila Weberb , Luana Cristina Berwigc , Rodrigo Agne Ritzeld , Ana Maria Toniolo da Silvae , Eliane Castilhos Rodrigues Corrêaf Childhood mouth-breathing consequences at adult age: ventilatory function and quality of life. Fisioter. mov. vol.27 no.2 Curitiba Apr./June 2014
2. To investigate associations between mouth breathing (MBr), nose breathing (NBr) and body posture classification and clinical variables in children and adolescents, by comparing patients with mouth breathing syndrome with a control group of similar age.
A total of 306 mouth breathing children and 124 nose breathing children were enrolled. Mouth breathers were more likely to be male, have more frequent and more severe nasal obstruction and larger tonsils than nose breathers.
Mouth breathers also exhibited higher incidence rates of allergic rhinitis, of thoracic respiratory pattern, high-arched palate and unfavorable postural classifications with relation to the control group.
The conclusion of the paper was that: Postural problems were significantly more common among children in the group with mouth breathing syndrome, highlighting the need for early interdisciplinary treatment of this syndrome.
Conti PB1, Sakano E, Ribeiro MA, Schivinski CI, Ribeiro JD. Assessment of the body posture of mouth-breathing children and adolescents. J Pediatr (Rio J). 2011 Jul-Aug;87(4):357-63
3. Study to evaluate the impact of the mouth breathing occurred during childhood on the body posture in the adult age. 24 adults, of both genders, aged from 18 to 30 years old with report of clinical manifestations of mouth breathing during the childhood composed the study group (SG).
The biophotogrammetric analysis demonstrated that the mouth breathing group showed more forward head posture confirmed by the angles A9 (p = 0.0000) and CL (p = 0.0414) and also by the cervical distance (p = 0.0079). Additionally, this group presented a larger angular measure of the lumbar lordosis (p = 0.0141) compared to the CG.
The results indicate that adults with mouth-breathing childhood have postural alterations, mainly in the head and lumbar column, which keeps for the whole life.
Milanesi JM, Borin G, Corrêa EC, et al. Impact of the mouth breathing occurred during childhood in the adult age: biophotogrammetric postural analysis. Int J Pediatr Otorhinolaryngol. 2011;75(8):999-1004.
Mouth Breathing and the Negative Impact to Voice (implications for Speech and Language)
1. The objective of this study was to determine the effects of chronic nasal obstruction on children’s vocal quality. Dysphonia affects 6% to 23% of children, and chronic nasal obstruction may participate in its pathophysiology.
Parents reported a dysphonia rate of 76.6% in NOG and a vocal abuse rate of 68.3%. Eight children from NOG (13.34%) showed mild conductive hypoacusia. Laryngeal lesions were detected in 35 children from NOG (58%): inflammatory processes (n=19), mucosal thickening (n=10), nodules (n=5), and cyst (n=1). In children from the NOG were observed higher scores for the Grade, Roughness, Breathiness, Aesthenia, Strain, Instability (GRBAS) perceptual scale (P<0.05), lower maximum phonation time values, and higher values to the s/z ratio, insufficient nasal resonance.
Relevant changes in perceptual auditory and acoustic vocal analyses and in the videolaryngoscopy were detected in children with nasal obstruction. These results showed the importance of the assessment of nasal obstruction in dysphonic children.
Consequences of chronic nasal obstruction on the laryngeal mucosa and voice quality of 4- to 12-year-old children.
J Voice. 2012 Jul;26(4):488-92. de Lábio RB1, Tavares EL, Alvarado RC, Martins RH.
2. The purpose of this study was to check the correlations among speech disorders and mouth breathing symptoms with the type of dentition and occlusion, using video recordings.
Considering speech disorders and dentition and occlusion data, the authors noted parallelism between distortion and crossbite, imprecision and bone deviation of lower midline line, locking and overjet, locking and overbite, frontal lisp and Angle Class III malocclusion, frontal lisp and malocclusion, frontal lisp and open bite, frontal lisp and crossbite; and frontal lisp and lower midline deviation.
Considering mouth breathing symptoms and dentition and occlusion data, they noted a symptom of parallelism between the protrusion of lower lip and overjet, accumulation of saliva on the labial commissures and crossbite, accumulation of saliva on the labial commissures and lack of intra-oral room.
Roberta Lopes de Castro MartinelliI; Érica Fabiana FornaroII; Charlene Janaina Milanello de OliveiraIII; Liege Maria Di Bisceglie FerreiraIV; Maria Inês Beltrati Cornacchioni RehderV Correlations between speech disorders, mouth breathing, dentition and occlusion Rev. CEFAC vol.13 no.1 São Paulo Jan./Feb. 2011 Epub Nov 19, 2010
3. This study assessed speech alterations in mouth-breathing children, and correlated them with the respiratory type, etiology, gender, and age.
Method: A total of 439 mouth-breathers were evaluated, aged between 4 and 12 years. The presence of speech alterations in children older than 5 years was considered delayed speech development. The observed alterations were tongue interposition (TI), frontal lisp (FL), articulatory disorders (AD), sound omissions (SO), and lateral lisp (LL). The etiology of mouth breathing, gender, age, respiratory type, and speech disorders were correlated.
The co-occurrence of two or more speech alterations was observed in 24.8% of the children.
CONCLUSIONS: Mouth breathing can affect speech development, socialization, and school performance. Early detection of mouth breathing is essential to prevent and minimize its negative effects on the overall development of individuals.
Hitos SF1, Arakaki R, Solé D, Weckx LL. Oral breathing and speech disorders in children. J Pediatr (Rio J). 2013 Jul-Aug;89(4):361-5.
4. The following study aimed to describe vocal characteristics in children aged five to twelve years with mouth breathing caused by four etiologies: chronic rhinitis, hypertrophy, hypertrophy + chronic rhinitis and functional condition, using perceptual evaluation and acoustic analysis.
Perceptual evaluation of the voice revealed that most mouth breathers presented hoarse and breathy voice, low pitch, normal loudness and hyponasal and laryngeal resonance.
Rosana Tiepo Arévalo1 , Luc Louis Maurice Weckx. Characterization of the voice of children with mouth breathing caused by four different etiologies using perceptual and acoustic analyses. Einstein. 2005; 3(3):169-173
5. This final study explored how nasal breathing improves the quality of inspired air, protects the airways, and promotes correct positioning of the phono-articulatory organs, ensuring good performance of the stomatognathic functions.
Its findings report that mouth breathing, a pathological condition, may be due to upper airway obstruction, sagging facial muscles, or habit; any individual who has exhibited this type of breathing for a minimum of six months should be considered a mouth breather. Among the consequences of mouth breathing are alterations in cranio-orofacial growth, speech, nutrition, body posture, sleep quality, and school performance. Overall, the mouth breather presents alterations in posture, tone, and mobility of lips, tongue and cheeks, resulting in less efficiency in stomatognathic functions: chewing, swallowing and speech, flaccid jaw elevator muscles, anterior head posture, maxillary atresia, and speech disorders.
It also concludes that speech can be altered due to flaccid facial muscles, incorrect positioning of the tongue, or structural problems of the oral cavity caused by malocclusion and/or deficiencies in facial growth and development.
The most commonly described speech disorders in mouth breathers are: anterior position of tongue during production of lingual dental phonemes, imprecision in bilabial (/p/,/b/,/m/) and fricative (/f/,/v/,/s/,/z/,/ʒ/,/∫/) phonemes in Portuguese, frontal lisp (FL), and lateral (LL) lisp. Children who are mouth-breathers can also have daytime sleepiness, poor brain oxygenation, or immature auditory processing. All of these complications can lead to learning disabilities.
Silvia F. HitosaI,*; Renata ArakakiII; Dirceu SoléIII; Luc L.M. WeckxIV Oral breathing and speech disorders in children. J. Pediatr. (Rio J.) vol.89 no.4 Porto Alegre July/Aug. 2013.
Creating Miracle Children by Patrick McKeown
Babies are born breathing in and out through their nose, their little tummy moving up and down as they take each breath. Nose breathing during childhood is transformative – it helps to ensure normal and correct development of the face and teeth, it is essential for deep sleep, concentration, good behaviour and academic performance.
Even though its functions are to improve oxygen uptake in the blood, filter, moisten and humidify incoming air before it is drawn into the body, the nose is often underused for the essential task of breathing. As early as a few months into life, many children change to habitual mouth breathing. This seemingly innocuous habit has detrimental effects on the development of the child and can result in lifelong health problems such as sleep disordered breathing.
The cause of mouth breathing is multi factorial and may be influenced by a combination of factors including genetic predisposition (if the baby has upper or lower airway issues including asthma), tongue tie (tissue holding the tongue down to the floor of the mouth) and environment (excessively warm or poorly ventilated home).
In 2010, the birth of my daughter Lauren brought tremendous joy to both Sinead and myself. Minutes after birth, she was drawn to the breast to feed. Breast feeding continued for a number of months until we realised that she wasn’t thriving as expected. We introduced the bottle to initially bridge the gap, and this soon became her primary mode of food. Little babies are clever and favour the bottle over the breast as it requires a lot less work to feed. Once the bottle is introduced, there is little chance of going back!
Lauren thrived and when she was three years of age, I noticed small changes to her breathing pattern. She was reverting more and more to mouth breathing. Her sleep was a little nosier and when she had a cold, I noticed her holding her breath during sleep. My daughter was becoming a mouth breather and showing signs of obstructive sleep apnoea- the very same breathing disorders that I experienced throughout my teenage years and which now are my field of work.
Over the next couple of years, I encouraged Lauren to nose breathe, teaching her a simple exercise to decongest the nose. When she was four years of age, I drove from Galway to Cork to see Dr Tony O’Connor who specialises in functional orthodontics. Tony explained that Lauren was tongue tied, had a narrow upper palate, was missing two adult teeth and her top jaw was dropping a little downwards. It was time for me to do something about it. Sinead and I booked Lauren for an adenoid/tonsillectomy. I also requested for the ENT surgeon to release Lauren’s tongue and lip tie. Despite the unpleasantness of having my daughter go through this operation, I felt it was absolutely necessary. Within days of the operation, she bounced back and was able to breathe silently and regularly through her nose during sleep.
My only small regret was that I didn’t get Lauren’s tongue tie released earlier. Tongue tie makes breast feeding very difficult for both baby and mother. To express milk from the breast, the tongue needs to move freely up and down. If the tongue is tied to the floor of the mouth due to a short frenulum, the baby doesn’t get enough milk and the mother often gets very sore.
At a recent sleep conference in Bordeaux, the speaker explained how midwives in Sixteenth century France had an extra long finger nail to release tongue ties of babies soon after birth. Bizarre as it may sound, it might have been the difference between life and death of the child. Our ancestors knew of the importance of free movement of the tongue. Maybe, it’s time to go back to basics?
While breast feeding is very important to provide proper nutrition to the baby, another vital function is that it encourages the baby to work the muscles of their face and jaw. While introducing the bottle is often necessary, it simply doesn’t provide a sufficient work out to help ensure adequate development of the jaws and nasal breathing.
Tongue tie increases the risk of habitual mouth breathing and prevents the baby from resting their tongue in the roof of the mouth. As the tongue sits in the roof of the mouth, it moulds the top jaw into a wide U shape. This helps to ensure a normal and healthy facial structure with sufficient room in both jaws to house all teeth. Breathing through the nose with the tongue in the correct resting posture helps ensure normal development of the face and jaws to produce good airways, beautiful facial features, good sized nasal cavity and straight teeth.
If the mouth is hanging open, the tongue is not able to rest in the roof of the mouth. Try it for yourself. Place three quarters of your tongue resting in the roof of your mouth. Then open your mouth and try to breathe. It is not easy. Chronic mouth breathers have a low resting tongue posture leading to narrow jaws and overcrowding of teeth (see references below #1-4). It is even more important to recognise that mouth breathing causes the face to sink downwards and the jaws don’t develop adequately on the face (see references #5-9). The result is increased risk of lifelong sleep disordered breathing including obstructive sleep apnoea, poor academic performance, behavioural issues and a less attractive face.
The negative effects of chronic mouth breathing are recognised within the medical and dental profession, yet very few parents are aware of it. A 2012 paper published in the International Journal of Pediatrics investigating the long-term changes to facial structure caused by chronic mouth breathing noted that this seemingly ‘benign’ habit has in fact immediate and/or latent cascading effects on multiple “physiological and behavioural functions”. The paper even suggested that habitual mouth breathing may even be connected to sudden infant death syndrome (see reference #10).
Animals and human infants are natural nasal-breathers. Although dogs are commonly thought to breathe through their mouth, they do so only to help regulate body temperature. Few healthy animals breathe through their mouths; the only exceptions are diving birds such as the penguin, gannet and pelican. Bearing in mind that the entire animal kingdom uses the nose for breathing, how is it that humans have developed such detrimental breathing habits?
I am not aware of any Irish study investigating the prevalence of mouth breathing in children, although I expect the habit is as common here as in other westernized countries. To identify the prevalence of mouth breathing in children of primary school ages from 6-9 years, researchers in Portugal examined 496 answered questionnaires from parents. It was found that 56.8% of children in this study breathed through their mouth (see reference #11). In another study conducted in Brazil, researchers concluded that 55% of the children involved in the study were mouth breathers (see reference #12).
Nasal breathing performs at least 30 functions on behalf of the body. Along with providing a sense of smell, the nose is nature’s way of preparing air before it enters the lungs. As the nostrils are much smaller than the mouth, they create approximately 50% more resistance in comparison to mouth breathing, resulting in a 10-20% greater oxygen uptake in the blood. Breathing optimally through the nose not only increases blood oxygenation, but also increases the amount of oxygen delivered to tissues and organs (see reference #13).
Having a stuffy nose adversely affects sleep both in children and adults. After a night spent breathing heavily through the mouth, a child may wake up exhausted, causing poor concentration and frustration at school. If this continues over a period of time, a psychological evaluation and possible diagnosis of ADD or ADHD may follow (see reference #14).
When I speak to any parent who has a child labelled with ADD or ADHD, my first piece of advice is to check their sleep habits.
- Are they breathing through their mouth?
- Are they twisting and turning during the night, waking up with the bed clothes tangled in the morning?
- Do they snore or hold their breath during sleep?
- Is their breathing audible during sleep?
Answering yes to any of these questions may suggest that the child is suffering the detrimental effects of sleep disordered breathing including obstructive sleep apnea.
Nasal breathing is of the utmost importance if you wish to improve your child’s quality of sleep. Any adult will understand the knock-on effect of crankiness and frustration when they have a poor night’s sleep – so how can a child face the day with boundless energy if their sleep is not right?
The good news is that sleep experts are becoming increasingly concerned about the impact of open mouth breathing during sleep, especially for children. Among these researchers is Dr. Christian Guilleminault, a leading figure in the field of sleep medicine. In the early 1970s, while working at the Stanford University Sleep Disorders Clinic, Dr. Guilleminault monitored the blood pressure of sleeping patients and discovered that when patients held their breath during sleep, their blood pressure dramatically increased. Dr. Guilleminault discovered and coined the condition obstructive sleep apnea (OSA).
Since then, Dr. Guilleminault has made many further discoveries in the field of sleep medicine. Among these, which I am delighted to include, is his recognition that: “the case against mouth breathing is growing, and given its negative consequences, we feel that restoration of the nasal breathing route as early as possible is critical.” This paper, published in 2015, goes on to say that “restoration of nasal breathing during wake and sleep may be the only valid ‘complete’ correction of paediatric sleep disordered breathing” (see reference #15).
As for Lauren, we are making great progress with establishing nasal breathing. She shows no signs whatsoever of sleep disordered breathing. As a child, I fell between the stools of modern medicine. Despite years of visiting doctors for asthma medication, I was never once encouraged to breathe through my nose. In 1997, I read an article in The Irish Independent about the work of Russian doctor Konstantin Buteyko who advocated the importance of breathing through the nose and bringing breathing volume towards normal. This simple advice completely changed my life. I am very grateful that I was able to recognise my daughters mouth breathing early on in her life so that I can assist her to develop normal breathing patterns.
The best advice that I can give parents is to monitor their child’s breathing pattern. Try to observe their breathing when they are concentrating while doing homework, sleeping or watching TV. Check how long your child maintains an open mouth posture. If they are spending at least 40% of the time with their mouth open, it is time to do something about it. If your child has nasal obstruction, I suggest that you teach them the nose unblocking exercise below. Mouth breathing is never normal. Nose breathing is essential to creating miracle children with beautiful faces, straight teeth and cognitive development.
Exercise to decongest the nose
The nose can be decongested for both allergic and non allergic rhinitis by holding the breath as follows: (if you have any serious medical complaint or are pregnant, this exercise is not suitable)
- Lauren takes a gentle breath in through her nose (if nose is totally blocked, take tiny breath through corner of mouth)
- Lauren gently breathes out through her nose
- She then pinches her nose with her fingers to hold her breath. She keeps her hand above her mouth so that mouth is visible
- Lauren sways her body or gently nods her head up and down to distract herself (Your child could also walk around while holding the breath)
- She pretends that she is underwater and she holds her breath for as long as possible
- When Lauren can hold her breath no more, she lets go of her nose and breathes through it
- She immediately calms her breathing
- She drops her shoulders and relaxes
Have your child wait for one minute and repeat. Continue to do this exercise until the nose gets free. Your child should practice any time the nose gets blocked.
When the child first breathes through their nose, their nostrils may flare and they might feel that they are not getting enough air. This is not because their nose is too small, it is because their breathing is too heavy. The respiratory centre within their brain has adjusted to a larger breathing volume and they are trying to take too much air in through their nose.
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