Asymmetry is often noted in facial palsy and Bell's palsy. The contours of the face are formed to a significant degree by the prominent parts of the bony facial skull. However, the mimic musculature also plays an important role for them. This becomes particularly clear in cases of chronic facial paresis: if nerve regeneration fails to occur and the mimic musculature atrophies, i.e. if it is broken down and partly replaced by fatty tissue, volume deficits occur in comparison to the unparalyzed opposite side and affected parts of the face flatten visibly. The various fatty tissue compartments superficial to the mimic muscles as well as the skin mantle of the face sink (descensus) and intensify the image of atrophy. The overall harmony of the face and also the symmetry of rest with a motionless facial expression without arbitrary/unintentional facial expressions are increasingly disturbed by this.