Microbiological composition associated with interleukin-1 gene polymorphism in subjects undergoing supportive periodontal therapy

J Periodontol. 2006 Aug;77(8):1397-402. doi: 10.1902/jop.2006.050212.

Abstract

Background: Interleukin-1 gene polymorphism (IL-1 gene) has been associated with periodontitis. The present study examined the subgingival microbiota by IL-1 gene status in subjects undergoing supportive periodontal therapy (SPT).

Methods: A total of 151 subjects with known IL-1 gene status (IL-1A +4845/IL-1B -3954) (IL-1 gene) were included in this study. Clinical data and subgingival plaque samples (40 taxa) were collected. These taxa were determined by the checkerboard DNA-DNA hybridization method.

Results: Gender, smoking habits (n-par tests), age, and clinical periodontal conditions did not differ by IL-1 gene status. IL-1 gene-negative subjects had a higher total bacterial load (mean difference, 480.4 x 10(5); 95% confidence interval [CI], 77 to 884 x 10(5); P <0.02). The levels of Actinobacillus actinomycetemcomitans (mean difference, 30.7 x 10(5); 95% CI, 2.2 to 59.5 x 10(5); P <0.05), Eubacterium nodatum (mean difference, 4.2 x 10(5); 95% CI, 0.6 to 7.8 x 10(5); P <0.02), Porphyromonas gingivalis (mean difference, 17.9 x 10(5); 95% CI, 1.2 to 34.5 x 10(5); P <0.05), and Streptococcus anginosus (mean difference, 4.0 x 10(5); 95% CI, 0.2 to 7.2 x 10(5); P <0.05) were higher in IL-1 gene-negative subjects, an observation specifically found at sites with probing depths <5.0 mm.

Conclusions: Bleeding on probing did not differ by IL gene status, reflecting clinical SPT efficacy. IL-1 gene-negative subjects had higher levels of periodontal pathogens. This may suggest that among subjects undergoing SPT, a lower bacterial load is required in IL-1 gene-positive subjects to develop the same level of periodontitis as in IL-1 gene-negative subjects.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Aggregatibacter actinomycetemcomitans / isolation & purification
  • Colony Count, Microbial
  • Dental Plaque / microbiology*
  • Dental Prophylaxis
  • Eubacterium / isolation & purification
  • Female
  • Humans
  • Interleukin-1 / genetics*
  • Male
  • Middle Aged
  • Periodontitis / genetics*
  • Periodontitis / microbiology
  • Periodontitis / prevention & control
  • Polymorphism, Genetic
  • Porphyromonas gingivalis / isolation & purification
  • Smoking
  • Streptococcus anginosus / isolation & purification

Substances

  • Interleukin-1