Class II division 1 malocclusions: the subdivision problem

The purpose of this study was to determine the frequency of occurrence of subdivisions, in Class II division 1 malocclusions. Sixty patients seeking orthodontic treatment at the dental college of King Saud University were selected. The results revealed that 45% of Class II division 1 patients examined had subdivisions. The most commonly affected side was the right (66.7%). Mandibular shift upon clo-sure was noted in 36% of the subdivision cases. Mandibular asymmetry was noted in 62.6% of the patients. It can be concluded from this study that subdivisions are a frequent finding in Class II divi-sion 1 malocclusions. Appropriate diagnosis of these cases should be done early in the mixed dentition phase, to avoid developing dental or skeletal asymmetries that can persist throughout adulthood.

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