Longitudinal growth changes in untreated subjects with Class II Division 1 malocclusion.

INTRODUCTION The purpose of this longitudinal study was to compare the craniofacial growth changes in untreated subjects with Class II Division 1 malocclusion with those in subjects with normal (Class I) occlusion from the prepubertal through the postpubertal stages of development, as defined by a biological indicator of individual skeletal maturity (cervical vertebral maturation method). METHODS The Class II Division 1 sample consisted of 17 subjects (11 boys, 6 girls). The Class I sample also consisted of 17 subjects (13 boys, 4 girls). The lateral cephalograms of the subjects in both groups were analyzed at 6 consecutive stages of development, from CS1 through CS6. The statistical comparisons of the growth changes in the study groups were performed with Mann-Whitney U tests. RESULTS Craniofacial growth in subjects with untreated Class II malocclusion is essentially similar to that in untreated subjects with normal occlusion at all developmental intervals, with the exception of significantly smaller increases in mandibular length (P <0.001) at the growth spurt (interval CS3-CS4) and during the overall observation period (intervals CS1-CS6). CONCLUSIONS Class II dentoskeletal disharmony does not tend to self-correct with growth in association with worsening of the deficiency in total mandibular length and mandibular ramus height.