Component analysis of Class II, Division 1 discloses limitations for transfer to Class I phenotype

Any malocclusion, most particularly Class II, must be diagnosed and treated on the basis of its many components and not simplified to one or only several spatial relationships. Research points out the inability of common approaches of treatment to transform a Class II, Division 1 phenotype to a facial pattern with normal skeletal relationships that would be expected with a Class I phenotype. These observations underscore the structural differences between the various classes of malocclusion in addition to the definition of treatment outcome as the cumulative effect of small-to-moderate changes in the various skeletal and dentoalveolar components of the malocclusion, rather than a major change in simply one of its components. Available data on component growth in untreated Class II further support these observations.