title: The influence of tobacco smoking on the outcomes achieved by root-coverage procedures: a systematic review.
abstract: BACKGROUND
  The authors conducted a systematic review to evaluate the effect of smoking on the clinical outcomes achieved by periodontal plastic surgery procedures in the treatment of recession-type defects.
  
  
  METHODS
  The authors performed an electronic search on MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL) for randomized controlled clinical trials, controlled clinical trials and case series that involved at least six months' follow-up. They looked for studies published through June 2008 that compared the outcome measures achieved by smokers and nonsmokers after they underwent periodontal plastic surgery procedures for treatment of gingival recession.
  
  
  RESULTS
  From a total of 632 references, the authors considered seven studies to be relevant. The meta-analysis indicated a statistically significant greater reduction in gingival recession (P < .001) and gain in clinical attachment level (P < .001) for nonsmokers when compared with smokers whose gingival recession was treated with subepithelial connective-tissue grafts. Additionally, nonsmokers exhibited significantly more sites with complete root coverage than did smokers (P = .001). For coronally advanced flaps, differences between the groups were not significant.
  
  
  CONCLUSIONS
  The results of this review show that smoking may negatively influence gingival recession reduction and clinical attachment level gain. Additionally, smokers may exhibit fewer sites with complete root coverage.
authors.affiliation: Division of Periodontics, Department of Stomatology, School of Dentistry, University of São Paulo, Av. Prof. Lineu Prestes, 2227 Cidade Universitária, 05508-000, São Paulo SP, Brazil. chambrone@usp.br
authors.forename: Leandro
authors.initials: L
authors.lastname: Chambrone
authors.forename: Daniela
authors.initials: D
authors.lastname: Chambrone
authors.forename: Francisco E
authors.initials: FE
authors.lastname: Pustiglioni
authors.forename: Luiz Armando
authors.initials: LA
authors.lastname: Chambrone
authors.forename: Luiz A
authors.initials: LA
authors.lastname: Lima
mesh_terms: D003238:Connective Tissue / Q000637:transplantation; D005889:Gingival Recession / Q000209:etiology / Q000601:surgery*; D005893:Gingivoplasty; D006801:Humans; D012907:Smoking / Q000009:adverse effects*; D013524:Surgical Flaps; D016896:Treatment Outcome