The influence of tobacco smoking on the outcomes achieved by root-coverage procedures: A systematic review

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. Types of Studies Reviewed. 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. Clinical Implications. 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.