Arch width changes in patients with Class II division 1 malocclusion treated with maxillary first premolar extraction and non-extraction method.

Background: The aim of this study was to determine arch width changes during maxillary first premolars extraction and non-extraction treatment in patients with Class II division 1 malocclusion.

Material And Methods: Dental casts of 91 Class II division 1 patients (36 males and 55 females) were evaluated. The minimum age of the subjects at the beginning of treatment was above 16 years.