Poor torquing of upper incisors will invite extrusion of these teeth. Because I have measured thousands of cases and that is what I have found. I think it is dead wrong, and completely unnecessary. Again please see Article No. 16 of the 'Schudy Chronicles' on the Internet. I have treated many cases with as much as 10 mm of overbite without intruding lower incisors.
All people change their philosophy through their life.
The two extremes of facial divergence would be 'Hypodivergence' and 'Hyperdivergence'. The terms 'Retrognathic' and 'Prognathic' are strictly measures of anteroposterior variations. We need hypodivergence and hyperdivergence to express vertical variations as well. The principal thesis of this study is that the vertical dimension is the most important to the clinical orthodontist and that vertical dysplasias are inseparably related to both open and closed bites. Too long the term 'Overbite' has been regarded as an ethereal, unapproachable abstraction related in some mysterious way to hereditary factors.