Botulinum toxin A in the mid and lower face and neck.

Botulinum toxins have been smoothing hyperkinetic lines in the upper face for over 15 years. More recently, their use has widened to include applications in the mid and lower face and neck to smooth, shape, and sculpt, blurring the line between science and art. Their use in the lower face, however, requires a thorough and detailed knowledge of not only facial and cervical anatomy, but also the complex interactions of muscles and the aesthetic and implications of a misplaced injection. Although proper patient selection and injection techniques do not guarantee optimal results, poor selection and techniques almost certainly guarantee disappointing results. In addition to its use as primary procedure, botulinum toxin is also an effective adjunct to other cosmetic procedures, enhancing and prolonging the benefits of surgery, soft tissue augmentation, and laser resurfacing.