Upper airway volume reduction coexists with skeletal Class II malocclusion. This malocclusion is characterized by a posterior mandibular position, a protruded maxilla, or both. Class III malocclusions are characterized by an anterior position of the mandible, a retruded maxilla, or both. Orthopedic-orthodontic treatment of Class II and III malocclusions should start during the period of mixed dentition to reduce the risk of more complex therapy in the future. Proper orthodontic diagnosis, including the upper airway area, allows orthodontic treatment modification, ensuring simultaneous respiratory function improvement. The aim of this study was to present how treatment methods for Class II and III malocclusions change the upper airways width parameters.

Key words: skeletal Class II, skeletal Class III, Class II malocclusion therapy, Class III malocclusion therapy, upper airways.