Orofacial function and breathing: why the mouth is much more than teeth

When we think about the mouth from a dental perspective, the first impulse is to think about teeth, gums, and occlusion. But the oral cavity is also the starting point for two of the most critical functions for life and development: breathing and feeding. And when these functions do not develop correctly, the consequences extend far beyond the mouth.

Orofacial function—the set of functions involving the muscles, structures, and movements of the stomatognathic system—is now recognized as a central axis of healthy child development. Its evaluation and management from the pediatric dental consultation is not optional: it is part of the evidence-based standard of care.

What is orofacial function and what does it include?

Orofacial function includes:

• Nasal breathing: The primary and most physiologically appropriate airway for craniofacial development.
• Sucking and swallowing: From infancy to mature adult swallowing, this process has developmental stages that can be altered.
• Mastication: Masticatory function is an essential mechanical stimulus for jaw growth.
• Phonation and speech: The articulation of sounds depends on the tonicity, position, and coordination of the tongue, lips, and palate.
• Resting tongue posture: The tongue at rest should rest against the hard palate. Its habitual position directly influences maxillary development.

When any of these functions are altered—whether due to habits, anatomy, pathology, or lack of stimulation—a cascade of effects is triggered that impacts facial structure, the airway, occlusion, and, ultimately, neurodevelopment.

Oral breathing: the pattern with the most consequences

Chronic oral breathing in children is one of the most frequent and, at the same time, most underestimated alterations in clinical practice. Its causes are multiple: nasal obstruction due to hypertrophy of turbinates or adenoids, chronic allergy, septal deviation, or simply a habit established without real anatomical obstruction.

The consequences of chronic oral breathing on craniofacial and systemic development include:

On facial growth

Nasal breathing generates positive internal pressure that molds the palate from the inside out. The tongue in a high position and resting on the palate acts as a natural expander. When the child breathes through the mouth, the tongue drops, the palate loses its expansion stimulus, and tends to become narrower and deeper. This is not just aesthetics: a narrow palate reduces the space of the upper airways and can perpetuate or worsen respiratory obstruction.

On posture

Oral breathing forces the child to extend their neck to widen the airway. This anterior cervical posture alters the biomechanics of the entire spine and has been associated with a higher prevalence of sleep bruxism in multiple cephalometric studies.

On sleep

A child who breathes through their mouth during the day almost inevitably does so at night as well. This predisposes to snoring, sleep fragmentation, apneas, and all the effects on neurodevelopment that we described in the article on childhood sleep and neurodevelopment.

On the immune system

The nose not only filters air: it humidifies it, warms it, and acts as the first barrier against pathogens. Children who breathe through their mouth are more prone to recurrent respiratory infections.

Atypical swallowing: when the primitive pattern persists

Infantile or visceral swallowing, characterized by the interposition of the tongue between the teeth when swallowing, is physiological until 3-4 years of age. When it persists beyond this age, it becomes a dysfunction with important clinical implications.

Atypical swallowing is associated with:

• Anterior open bites
• Protrusion of upper incisors
• Difficulties in the articulation of linguoalveolar phonemes
• Masticatory inefficiency

The management of atypical swallowing requires collaboration between the pediatric dentist, orthodontist, and speech therapist. Orthodontics that is not accompanied by myofunctional therapy has significantly higher relapse rates, precisely because the muscular cause was not treated.

The transdisciplinary approach: why the pediatric dentist cannot work alone

Orofacial function is, by nature, a territory shared between disciplines. The pediatric dentist identifies the structural consequences and activates the diagnostic process, but effective management requires:

• Speech therapists/logopedists for myofunctional therapy, correction of swallowing, and speech.
• Otorhinolaryngologists for the evaluation and management of upper airway obstructions.
• Pediatric allergists when nasal obstruction has an allergic origin.
• Pediatricians for a comprehensive view of development.
• Orthodontists when orthopedic intervention can improve airway space.

The role of the pediatric dentist in this team is to be the first to suspect, the first to ask, and the articulator of the transdisciplinary diagnostic process.

How to evaluate orofacial function in your practice?

Evaluating orofacial function does not require special equipment. Observe:

• Resting lip posture: Are the lips sealed or slightly open?
• Tongue posture: Ask the child to rest their tongue. Does it go up to the palate or stay on the floor of the mouth?
• Breathing type: Observe the breathing pattern during the consultation. Does the child breathe through their nose or mouth?
• Swallowing: Offer water and observe if there is contraction of the lips or chin during swallowing.
• Lip and cheek tonicity: Are they hypotonic? Are there digital sucking habits?
• Palate conformation: Is it narrow and deep? Is there asymmetry?

These observations, integrated into the usual clinical record, turn each consultation into an opportunity for early detection.

Conclusion

Orofacial function is the bridge between the mouth and the rest of the body, between dental structure and neurodevelopment. A pediatric dentist who evaluates how their patient breathes, swallows, and chews—not just how their teeth are—is practicing the comprehensive pediatric dentistry that scientific evidence demands today.

At Neurotrainers, we train professionals who see the whole child, not just their mouth.

Are you interested in delving deeper into the approach to orofacial function? Discover our transdisciplinary course on orofacial function, airways, and sleep, created by Dr. Claudia Restrepo Serna based on updated scientific evidence.