Summarized by Dr. Hani Alhebshi.
Class II subdivision cases were defined as patients who have complete class II molar relationship on one side and class I on the other side.
One Study considered that a Class II subdivision required at least a half cusp difference between the right and left sides (For example, a full cusp Class II relationship on the right side and a half cusp Class II relationship on the left side).
Many orthodontists from British schools do not consider a subdivision case as a type in the classification. However they just see cases of class II as division one or two and treat each case separately according to the clinical situation.
Sanders et al., stated that the primary contributing factor responsible for a Class II subdivision malocclusion is a deficient mandible, due to either reduced ramus height or mandibular length, on the Class II side. However, other studies have reported that the main factor contributing to the asymmetric anteroposterior relationships in Class II subdivision malocclusions is the dentoalveolar component