In this lecture, four major issues are going to be discussed:

I. How does mandibular advancement trigger condylar growth? The presence of a "Mechano-Transduction Mediator that feels mechanical force created by the advancement and converts these forces into condylar growth" will be presented.

II. The effect of functional appliances remains controversial. Why and how to solve it? In this section, degree of advancement, duration and mode of mandibular advancement and their effects on condylar growth are presented.

III. A treatment protocol based on basic experimental outcomes is presented and its long term stability is highlighted.

IV. The role gene therapy could play in the future of our profession?