Differences in dental arch morphology among adult females with untreated Class I and Class II malocclusion.

The purpose of the study was to evaluate differences in dental arch morphology among an orthodontic sample of 386 untreated adult females between 17 and 68 years of age, categorized by age group (17-25 years, 26-35 years, or 35+ years) and malocclusion (Class I, Class II division 1, or Class II division 2). The results show that both maxillary and mandibular dental arch size were significantly larger for the younger age group. Arch shape was relatively shorter and wider for the oldest age group. Palatal height was greatest for the youngest age group and least for the oldest group. Subjects with Class II malocclusion had significantly smaller arches, greater maxillary incisor irregularity, and less mandibular incisor irregularity than patients with Class I malocclusion. Subjects with Class II division 1 malocclusion had greater palatal heights and relatively longer/narrower maxillary dental arches than subjects with Class II division 2 malocclusion.