Microbiological composition associated with interleukin-1 gene polymorphism in subjects undergoing supportive periodontal therapy.
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.
Agerbaek
Mette R
MR
Institute of Medical Microbiology and Immunology, University of Arhus, Arhus, Denmark.
Lang
Niklaus P
NP
Persson
G Rutger
GR
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016976:Aggregatibacter actinomycetemcomitans / Q000302:isolation & purification; D015169:Colony Count, Microbial; D003773:Dental Plaque / Q000382:microbiology*; D003777:Dental Prophylaxis; D005051:Eubacterium / Q000302:isolation & purification; D005260:Female; D006801:Humans; D007375:Interleukin-1 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D010518:Periodontitis / Q000235:genetics* / Q000382:microbiology / Q000517:prevention & control; D011110:Polymorphism, Genetic; D016966:Porphyromonas gingivalis / Q000302:isolation & purification; D012907:Smoking; D034366:Streptococcus anginosus / Q000302:isolation & purification
D007375:Interleukin-1