RESUMO
BACKGROUND: To date, no standardized minimally invasive approach for the treatment of excessive gingival display exists. OBJECTIVES: This systematic review aims to assess the evidence in the literature regarding the role of botulinum toxin injection in the management of gummy smile. METHODS: All publications through December 2014 and pertaining to the subject were electronically searched in PubMed, Embase, Scopus, and Web of Science, and the bibliographies of retrieved articles were manually screened. RESULTS: Out of 33 articles, 29 were discarded based on exclusion criteria. Although all 4 selected articles were in line with a role for botulinum toxin injection in the treatment of gummy smiles and the importance of targeting the levator labii superioris alaeque nasi muscle, studies differed in the type and the dose of toxin administered and the technique adopted. CONCLUSIONS: Injection with botulinum toxin is a novel, safe, and cosmetically effective treatment for gummy smile when performed by experienced practitioners. However, further randomized controlled trials are warranted. LEVEL OF EVIDENCE 4: Therapeutic.
