Herbst appliance effects on pharyngeal airway ventilation evaluated using computational fluid dynamics

Area of Science:

• Orthodontics
• Biomedical Engineering
• Respiratory Physiology

Background:

• The pharyngeal airway (PA) is critical for respiration.
• Orthodontic interventions can influence airway dimensions and airflow.
• Understanding the impact of orthodontic appliances on airway ventilation is essential for patient health.

Purpose of the Study:

• To investigate the effect of the Herbst appliance on pharyngeal airway ventilation.
• To compare airway ventilation changes between patients treated with a Herbst appliance and a control group.

Main Methods:

• Utilized computational fluid dynamics (CFD) for airway analysis.
• Employed cone-beam computed tomography (CBCT) to create 3D models of the pharyngeal airway.
• Compared pressure and velocity parameters in the PA between 21 Class II patients (Herbst group) and 19 Class I controls.

Main Results:

• The Herbst group showed a significantly greater increase in oropharyngeal airway velocity (1.95 m/s) compared to the control group (0.67 m/s).
• A significantly larger decrease in laryngopharyngeal airway velocity was observed in the Herbst group (1.37 m/s) versus the control group (0.57 m/s).

Conclusions:

• The Herbst appliance demonstrably improves ventilation in both the oropharyngeal and laryngopharyngeal airways.
• These findings offer valuable insights for evaluating obstructive sleep apnea treatment strategies in pediatric and adolescent populations.