Experimental gingivitis in cigarette smokers

Abstract

To assess clinical and microbiological changes during experimental gingivitis in cigarette smokers and non-smokers. Eleven current smokers (>/=5 years) and 11 (never-) non-smokers periodontally healthy or with gingivitis (PPD</=4 mm) were included. According to the original model (Löe et al. 1965), an experimental 3-week plaque accumulation period resulting in experimental gingivitis and a subsequent 2-week period of optimal plaque control were performed. Subgingival plaque samples were collected at days 0, 21 and 35 from one site per quadrant, pooled and analysed using checkerboard DNA-DNA hybridization. Smokers {mean age: 24.7+/-2.2 [standard deviation (SD)] years, range 21-28 years} had a mean lifetime cigarette exposure of 6.4+/-2.8 (SD) pack-years, while non-smokers presented with a mean age of 23.1+/-2.2 (SD) years (range 21-29 years). Between days 0, 21 and 35, no statistically significant differences in mean Plaque and mean Gingival Index scores were observed between smokers and non-smokers. In both smokers and non-smokers, mean total DNA probe counts did not significantly differ nor increase between days 0 and 21. Also, between days 21 and 35 they did not significantly differ nor decrease. This was also true for the various proportions of bacterial complexes. Both current smokers and (never-) non-smokers reacted to experimental plaque accumulation with gingival inflammation. Periodontal and microbiological parameters assessed in current cigarette smokers did not significantly differ from those in non-smokers during an identical period of experimental plaque accumulation. Hence, the early host response to the bacterial challenge appears to be of similar magnitude and timing in both groups.