Progression of periodontal disease in a maintenance population of smokers and non-smokers: A 3-year longitudinal study

Background: Cigarette smoking is accepted as an important factor that increases the risk for the initiation and progress of chronic periodontitis. However, the effect of cigarette smoking on the recurrence of disease in patients undergoing regular maintenance therapy is less understood. Therefore, we set out to assess disease progression longitudinally in smoking and non-smoking subjects with chronic periodontitis undergoing periodontal maintenance therapy every 3 to 4 months. Methods: A total of 108 subjects undergoing regular maintenance therapy for chronic periodontitis were followed over a 3-year period. Self-reports of smoking status were confirmed by analysis of exhaled carbon monoxide concentrations. Clinical parameters (plaque index [PI], bleeding on probing [BOP], clinical attachment loss [CAL], probing depth [PD], and tooth loss) were recorded at yearly reevaluation visits. The study was carried out in a university hospital setting. Results: Longitudinal measurements were obtained from 81 (75%) subjects. There were no differences in inflammatory indices at baseline or over time (PI and BOP; both P>0.05) between smokers (N = 16; age: 54 +/- 6 years) and non-smokers (N = 65; age: 59 +/- 14 years). Likewise, there was no difference between the smoking groups with respect to disease progression (measured as changes in prevalence [number] and proportion [percentage] of progressing sites and as mean CAL, PD, and tooth loss; all P>0.05). Conclusion: In this small population, regular maintenance treatment in a cross-section of highly motivated subjects with chronic periodontitis seemed to be equally successful in preventing progressive periodontal tissue destruction in current smokers and current non-smokers.