Class II malocclusion does not self-correct in growing patients. The Class II skeletal pattern is established early and remains until puberty if no orthodontic intervention is performed. To this date, several authors have discussed the relationship of the initial malocclusion characteristics with the effectiveness of orthodontic treatment and the stability of the corrections obtained.
Normally, orthodontic treatment takes a long time and uses complex techniques, usually achieving good results; however, these results may be lost in varying degrees after the removal of appliances and retainers. Orthodontic relapse includes crowding or spacing of teeth, and loss of overbite, overjet correction, and loss of Class II molar relationship correction.
Orthodontic changes of the position of the first permanent molars have a great tendency to relapse. Some authors affirm the with time, in adults, changes that occur in molar relationship are always towards Class II relation. The changes are of small magnitude and independent of the type of initial malocclusion and the type of treatment. Other authors suggest that, in the long-term, there is relapse in molar relationship and that changes in incisor position and intercuspation of the posterior teeth are statistically significant.
The real problem is that we don’t have clear the real etiology of a Cl II malocclusion. Only if we have the understanding of the morphologic characteristics of a malocclusion can we know what needs to be changed in order to treat our patients, growing and adults, from a full Cl II molar relationship, to a stable Cl I, correcting also the skeletal Cl II.
Some of the common mistakes in treating a Cl II is wrong diagnosis, high pull headgear, premolar extractions and the use of Cl II elastics.