Evaluation of the effect of smoking on nonsurgical periodontal therapy in generalized aggressive periodontitis

Aggressive periodontitis seen in systemically healthy individuals and has a familial pattern, is usually separated from chronic periodontitis by severe bone destruction and rapid attachment loss that occurs at an early age. Aggressive periodontitis is classified into localized and generalized forms depending on the number of teeth affected by the disease. Generalized aggressive periodontitis (GAgP) is characterized by interproximal attachment loss affecting at least 3 permanent teeth other than the first molars and incisors and periodontal tissue destruction is usually inconsistent with the amount of local etiological factors. Today questions still exist about treatment and prognosis of aggressive periodontitis. Few studies have investigated possible effects of smoking on the treatment outcomes in patients with GAgP. The present study aims to evaluate the possible effects of smoking on the clinical, biochemical and microbiological outcomes of non-surgical periodontal treatment in GAgP patients. Fourteen smoker and 13 non-smoker GAgP patients were included in the present study. At baseline, whole mouth clinical periodontal measurements consisting probing depth, clinical attachment level, bleeding on probing and plaque index were recorded and these measurements were repeated 1, 3 and 6 months after completion of non-surgical periodontal treatment. Saliva, gingival crevicular fluid and blood samples were obtained at the same time points. Interleukin- (IL)-17A, IL-17E, IL-1β, IL-6 and tumour necrosis factor-alpha (TNF-) levels were determined in all samples. Moreover, subgingival plaque samples were obtained and presence as well as quantities of 11 different bacterial species were determined. All data were evaluated by appropriate statistical tests. There were no significant differences in clinical parameters between the non-smoker and smoker groups except the higher plaque scores in the non-smoker group at 6-month control (p<0.05). There were significant differences in the biochemical parameters between the smoker and non-smoker groups (p<0.05). The microbiological analyses indicated more Gram-negative bacteria in the smoker group than the non-smoker group (p <0.05). Moreover, Gram-positive bacteria were more frequent in the non-smoker group than the smoker group at baseline (p<0.05). Gram-negative bacteria repopulated in the smoker group much faster than the non-smoker group (p<0.05). In conclusion, although clinical periodontal parameters revealed no significant differences between the smoker and non-smoker GAgP patients after the non-surgical periodontal treatment, it can be suggested that smoking has negative effects on the biochemical and microbiological outcomes.