[Upper airways: tridimensional analysis and effect of treatment by functional appliances]

This article revolves around three questions summarizing the main lines of research into the upper airways conducted at Aarhus University. 1. Can the upper airway be reliably evaluated by Cone Beam CT (CBCT)? 2. Is there a link between airway dimension and craniofacial morphology? 3. Do functional appliances increase the volume of the upper airway? 1. The CBCTs of 34 patients were used for this three-dimensional assessment of the upper airway, comparing linear measurements, surfaces and volumes. 2. CBCTs of 90 healthy adults with skeletal class I, II or III were compared. The dimensions of the upper airway were correlated with the cephalometric measurements in 3D. 3. A retrospective CBCT study investigated changes in the upper airway after functional appliance therapy in 20 patients. 1. The upper airway cannot be correctly described using linear measurements. 2. No correlation could be identified between the size and morphology of the upper airway and the morphology of sagittal skeletal class I, II or III malocclusions. 3. An increase in volume of the upper airway was observed after treatment with functional appliances, mainly at the level of the oropharynx. A three-dimensional analysis by CBCT gives a better representation of the anatomical characteristics of the upper airway. This type of 3D analysis revealed a positive effect of treatment by functional appliances on the oropharynx in healthy, growing patients.