Botulinum Toxin and Smile Design.

Smiles with excessive gingival display exceeding 3 mm are considered unattractive. Excessive muscular contraction of lip elevator muscles is the etiology in most cases, and other factors, such as excessive vertical dimension of the maxilla and altered passive dental eruption resulting in the presence of excessive gingival tissue, account for the etiologic factors in others. Botulinum toxin type A (BTX-A) blocks muscular contraction by inhibiting the release of acetylcholine in muscles' endplates. The author has proven BTX-A to be an effective treatment alternative for the correction of these conditions affecting smile esthetics. This article explains how this is accomplished.