The Dentist’s Role in Pediatric Sleep-Disordered Breathing: Insights from Dr. Audrey Yoon

In a recent lecture, Dr. Audrey Yoon shared research and clinical insights into how orthodontic interventions, particularly palatal expansion, can influence airway health, sleep-disordered breathing, and even the immune system in children. Her work highlights dentistry’s pivotal role in the early detection and management of pediatric sleep disorders.

Understanding the Airway Beyond Anatomy

Traditional thinking often measures treatment success in terms of airway size alone. Dr. Yoon challenged this notion, explaining that airway collapsibility — not just volume — is critical in obstructive sleep apnea (OSA). Using computational fluid dynamics (CFD) calibrated with biologic and physiologic data, her team demonstrated that palatal expansion reduces nasal resistance, slows turbulent airflow, and stabilizes the pharyngeal airway.

She illustrated the concept with a vivid analogy: like smoke being pulled back into a moving car through a half-open window, turbulent airflow in a narrow nasal passage creates negative pressure that collapses the airway. Expansion restores smoother, laminar airflow, reducing collapsibility and improving airway stability during sleep.

Palatal Expansion and Lymphoid Tissue

Dr. Yoon also explored how palatal expansion can affect lymphoid tissues such as adenoids and tonsils. She presented the case of a five-year-old patient with enlarged tonsils and severe snoring. Initially referred for tonsillectomy, the child instead underwent palatal expansion combined with adjunctive oral appliances. Unexpectedly, her tonsil size decreased significantly, and her surgery was canceled. Beyond the medical benefits, the patient was so inspired by the experience that she now dreams of becoming an orthodontist.

To test whether this was an isolated outcome or a broader phenomenon, Dr. Yoon collaborated with UCSF radiology to study tonsil and adenoid volume changes using 3D imaging. Among 60 patients with high-arched palates and enlarged tonsils, 90–95% experienced significant reductions in lymphoid tissue volume after expansion. On average, adenoids shrank by 60% and tonsils by 38% over the course of a year.

The Role of Nitric Oxide

One of the most intriguing mechanisms behind these findings involves nitric oxide, a powerful neurotransmitter and immune regulator produced in the nose and paranasal sinuses. Palatal expansion increases nasal breathing and the surface area for nitric oxide production. By shifting children from mouth breathing to nasal breathing, expansion may reduce inflammation, strengthen immunity, and contribute to the observed reductions in tonsil and adenoid size.

Clinical Implications and Controversies

While palatal expansion shows promise as a non-invasive intervention, Dr. Yoon emphasized that it should not be viewed as a replacement for adenotonsillectomy. Surgical removal of enlarged tonsils and adenoids still provides immediate relief for many children with severe symptoms. However, expansion may offer long-term benefits for children with mild to moderate cases or those who are otherwise asymptomatic but at risk.

She also highlighted the importance of adhering to AAPD guidelines: in the primary dentition stage, early treatment is recommended for conditions such as crossbites, persistent oral habits, or airway problems that are unlikely to self-correct.

A Call to Action for Dentistry

Dr. Yoon concluded by stressing the role of dentists in pediatric sleep-disordered breathing:

• Early detection of airway and growth issues

• Growth modification through orthodontic interventions

• Patient and parent education on sleep and breathing health

• Interdisciplinary collaboration with sleep physicians, ENTs, and pediatricians

• Long-term monitoring to ensure healthy development into adolescence and adulthood

Her message is clear: dentists are uniquely positioned to build healthier anatomical foundations that can last a lifetime. Though many questions remain, her research and clinical work open the door to new possibilities in how dentistry contributes to sleep medicine.