• aspirin;
  • periodontal disease;
  • scaling and root planing;
  • smoking


The objective of this parallel, double-blind, randomized pilot study was to determine the effect of a daily dose of 325 mg of aspirin (ASA) on the clinical outcomes of scaling and root planing in a selected group of adult smokers.


The response to periodontal therapy is inferior among smokers compared to non-smokers. Long-term intake of ASA has been shown to exert a positive impact on reducing both the prevalence and severity of periodontitis, among high-risk groups of subjects such as heavy smokers and diabetics. It is reasonable to assume that systemic administration of ASA in conjunction with reduction of the bacterial load by scaling and root planing may improve and prolong the benefits of periodontal therapy. To date, only few prospective interventional clinical studies have specifically addressed the periodontal needs of smokers.


The study includes 24 smokers. The following clinical parameters were measured preoperatively and at 3, 6, 9 and 12 mo postoperatively: (i) gingival index; (ii) plaque index; (iii) probing depth; (iii) probing attachment level; (iv) gingival recession; and (v) bleeding scores. Study subjects received scaling and root planing over several visits and were randomly assigned into two equal groups; a control group (C), which received a placebo and a test group (T), which took a daily dose of 325 mg ASA. No additional therapy was provided over the 1 year observation period.


There were more statistically significant differences (p < 0.05; one- tailed) between pretest and posttest scores in the T group than in the C group. Mean percent increase in sites with probing depth 1–3 mm (T: 8.78; C: 7.21); mean percent reduction in sites with probing depth 4–6 mm (T: −7.25; C: −5.09 not statistically significant, NS); mean percent reduction in sites with probing depth ≥ 7 mm (T: −1.42; C: −02.09); mean percent reduction in sites with probing attachment level 3–4 mm (T: −3.63; C: 0.48 NS); mean percent reduction in sites with bleeding on probing (T: −12.37; C: −2.59 NS) (p < 0.05, NS).


Daily intake of 325 mg of ASA following scaling and root planing improved treatment outcomes in smokers, without an increase in gingival bleeding tendency. ASA promoted a higher incidence of shallow pockets and more gain in attachment level.