Zhao Z et al. (2021). Effects of mouth breathing on facial skeletal development in children: a systematic review and meta-analysis. BMC Oral Health. (被引用 97 次)
Harari D et al. (2010). The effect of mouth breathing versus nasal breathing on dentofacial and craniofacial development in orthodontic patients. The Laryngoscope. (被引用 246 次)
Lin L et al. (2022). The impact of mouth breathing on dentofacial development: A concise review. Frontiers in Public Health. (被引用 93 次)
Zhang J et al. (2024). Adenoid facies: a long-term vicious cycle of mouth breathing, adenoid hypertrophy, and atypical craniofacial development. Frontiers in Public Health.
Primarti R et al. (2025). Mouth Breathing and Its Impact on Sleep Breathing Disorders in Children. Clinical, Cosmetic and Investigational Dentistry.
Izu SC et al. (2010). Obstructive sleep apnea syndrome (OSAS) in mouth breathing children. Brazilian Journal of Otorhinolaryngology. (被引用 74 次)
Key Findings
Mouth breathing causes measurable skeletal changes. A meta-analysis of 10 studies (Zhao et al., 2021, BMC Oral Health) found backward/downward rotation of both maxilla and mandible (p<0.0001), steeper occlusal planes, labial inclination of upper incisors, and pharyngeal airway stenosis in mouth-breathing children.
Narrow palate, posterior crossbite, and Class II malocclusion are the most consistently reported dental consequences. Harari et al. (2010, The Laryngoscope, n=116) found posterior crossbite in 49% of mouth breathers vs. 26% of nasal breathers (p=.006).
Adenoid/tonsillar hypertrophy is the primary driver, creating a self-reinforcing vicious cycle. Zhang et al. (2024) described 20 years of evidence: airway obstruction → mouth breathing → perioral muscle imbalance → skeletal malocclusion → further airway constriction ("adenoid facies cycle").
Effects are age-dependent; early intervention is most effective. Mattar et al. (2011) showed significant normalization of mandibular growth direction within ~28 months after adenotonsillectomy in children aged 3–6. The growth period (before age 12) is the critical window.
Mouth breathing is strongly linked to sleep-disordered breathing. Primarti et al. (2025, n=343) found a 4.24-fold higher risk of SDB in mouth breathers (95% CI: 2.70–6.65). Izu et al. (2010) found 42% of 248 mouth-breathing children had confirmed OSAS.
Limitations
Causality remains debated: some evidence suggests narrow craniofacial anatomy predisposes to mouth breathing rather than the reverse.
High heterogeneity in study designs; inconsistent diagnostic criteria for "mouth breathing" across studies.
Mostly cross-sectional or retrospective designs; limited long-term follow-up data on durability of skeletal improvements post-intervention.
Key References
Zhao Z et al. (2021). Effects of mouth breathing on facial skeletal development in children: a systematic review and meta-analysis. BMC Oral Health. (97 citations)
Harari D et al. (2010). The effect of mouth breathing versus nasal breathing on dentofacial and craniofacial development in orthodontic patients. The Laryngoscope. (246 citations)
Lin L et al. (2022). The impact of mouth breathing on dentofacial development: A concise review. Frontiers in Public Health. (93 citations)
Zhang J et al. (2024). Adenoid facies: a long-term vicious cycle of mouth breathing, adenoid hypertrophy, and atypical craniofacial development. Frontiers in Public Health.
Primarti R et al. (2025). Mouth Breathing and Its Impact on Sleep Breathing Disorders in Children. Clinical, Cosmetic and Investigational Dentistry.
Izu SC et al. (2010). Obstructive sleep apnea syndrome (OSAS) in mouth breathing children. Brazilian Journal of Otorhinolaryngology. (74 citations)