Smoking may affect root coverage outcome: a prospective clinical study in humans

BACKGROUND: Cigarette smoking has been shown to negatively influence healing following periodontal therapeutic procedures. Therefore, the aim of this study was to evaluate the impact of smoking on clinical outcome of root coverage following subepithelial connective tissue graft (CTG) surgery. METHODS: Eighteen defects were treated in 15 patients (seven smokers and eight non-smokers) who presented canine and pre-molar Miller Class I and II recessions. CTG was performed and clinical measurements were obtained at baseline, and 30, 60, 90, and 120 days after surgery. Clinical measurements included plaque and gingival indexes, gingival recession, probing depth, clinical attachment level, gingival thickness, and keratinized tissue width. RESULTS: Intragroup analysis showed that CTG was able to promote root coverage, increase gingival thickness, and improve clinical attachment level in both groups (P < 0.05). On the other hand, intergroup analysis demonstrated that smokers presented with a lower percentage of root coverage (58.84% +/- 13.68% versus 74.73% +/- 14.72%), less clinical attachment level gain (2.54 +/- 0.79 mm versus 2.00 +/- 1.04 mm), and deeper probing depths (1.56 +/- 0.53 mm versus 2.35 +/- 0.67 mm) than non-smokers (P < 0.05). Moreover, 4 months after CTG, smokers presented more keratinized tissue compared to non-smokers (3.30 +/- 0.86 mm versus 4.50 +/- 1.16 mm) (P < 0.05). CONCLUSION: Within the limits of the present study, it can be concluded that cigarette consumption may present a negative impact on root coverage outcome by CTG and, therefore, may represent one more challenge for periodontal plastic therapy.