Vertical facial pattern and orthodontic stability Part II: Facial axis changes and stability

Lateral cephalograms and study casts of 55 patients were evaluated to determine if any relationships exist between Facial Axis changes occurring during and after active treatment and either the pretreatment Jarabak Facial Height Quotient or the amount of post-treatment occlusal change, as measured with a weighted PAR score. No significant relationships could be found. There was instead a wide range of individual variation in the post-treatment behaviour of both the Facial Axis and the weighted PAR score, in both the total sample and three Jarabak Facial Height subgroups. Long-term Facial Axis changes occurring in individual patients, however, were not necessarily associated with occlusal deterioration. Since the Facial Axis is likely to change to some extent in the long-term, it was suggested that widely recommended methods for Facial Axis control during treatment should be considered primarily for functional and aesthetic reasons, rather than on the basis of directly ensuring long-term occlusal stability.