ORIGINAL ARTICLE Effect of teenage smoking on the prevalence of periodontal bacteria Anna Maria Heikkinen & Janne Pitkäniemi & Kirsti Kari & Riitta Pajukanta & Outi Elonheimo & Markku Koskenvuo & Jukka H. Meurman Received: 28 June 2010 / Accepted: 2 February 2011 / Published online: 22 February 2011 # Springer-Verlag 2011 Abstract The aim of our study was to investigate how teenage smoking affects the prevalence of periodontal bacteria and periodontal health with the hypothesis that smoking increases the prevalence of the bacteria. Oral health of 264 adolescents (15- to 16-year-olds) was clinically examined, and their smoking history was recorded. The participants also filled in a structured questionnaire recording their general health and health habits. Pooled subgingival plaque samples were taken for polymerase chain reaction analysis of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tanner- ella forsythia, Prevotella intermedia, Prevotella nigrescens, and Treponema denticola. The prevalence of P. intermedia (21% vs. 4%, p =0.01) and T. forsythia and T. denticola Clinical relevance Teenage smokers seemed to be at higher risk for early development of periodontitis; they also need to be helped in smoking cessation by dental professionals. A. M. Heikkinen (*) : O. Elonheimo Network of Academic Health Centers, Department of General Practice and Primary Health Care, Institute of Clinical Medicine, University of Helsinki, PL 41, Helsinki 00014, Finland e-mail: amkheikk@mappi.helsinki.fi A. M. Heikkinen : K. Kari : R. Pajukanta : J. H. Meurman Institute of Dentistry, University of Helsinki, Helsinki, Finland A. M. Heikkinen : J. Pitkäniemi : M. Koskenvuo Hjelt Institute, University of Helsinki, Helsinki, Finland J. H. Meurman Department of Oral and Maxillofacial Diseases, Helsinki University Central Hospital, Helsinki, Finland Clin Oral Invest (2012) 16:571–580 DOI 10.1007/s00784-011-0521-3 (23% vs. 8%, p <0.05, for both) was higher among female smokers than among non-smokers. T. forsythia and T. denticola were more often associated with bleeding on probing (29% vs. 12%; 25% vs. 10%, respectively) and deep pockets (25% vs. 15%; 23% vs. 10%, respectively) with smokers than non-smokers. Among the girls, a significant association was found between pack-years and the preva- lence of P. nigrescens (p <0.007). In both genders, A. actinomycetemcomitans and P. gingivalis were rare in this study. To conclude, periodontal bacteria were associated with higher periodontal index scores among all teenage smokers. Smoking girls harbored more frequently certain periodontal bacteria than non-smokers, but this was not seen in boys. Hence, our study hypothesis was only partly confirmed. Keywords Aggregatibacter actinomycetemcomitans . Porphyromonas gingivalis . Tannerella forsythia . Prevotella intermedia . Prevotella nigrescens . Treponema denticola Introduction The effect of smoking on oral health has not been systematically studied among adolescents. Smoking has been strongly linked with worse dental health among adults when compared with non-smokers. Smoking is known to affect the oral cavity both directly and systemically [1]. Smoking is an undisputable risk factor for periodontal health increasing the age-related risk regarding attachment loss and deep pockets [2, 3]. The latest national report on youth in Finland shows that 8% of both the girls and boys smoke at the age of 14 years. The respective figure at age of 16 is 23% in both genders [4].