1997 Volume 39 Issue 3 Pages 368-374
Periodontal pockets of 38 periodontal patients who had received no antibiotic therapy within 6 months of sampling, were examined for tetracycline-resistance genes (tet M and tet B) and the Actinobacillus actinomycetemcomitans gene by the polymerase chain reaction. Positive rates of tet M and tet B were respectively 60.5% and 34.2% (significant, chi square test, p<0.05). Positive rates of tet M were 31.6% in shallow pockets (=4 mm, n=19) and 89.5% in deep pockets (>4mm, n=19) (significant, chi square test, p<0.01). Pos-itive rates of A. actinomycetemcomitans were 44.7% in all patients. Positive rates of tet in A. actinomycetemcomitans-positive sites were 52.9% (tet M) and 41.1% (tet B). Tetracycline-resistance genes (tet M and tet B) seemed to already exist at high rates in periodontal pockets before antibiotic therapy. Their presence seemed to depend on the tet kind and the circumstances. Periodontal pathogenic microbes such as A actinomycetemcomitans may acquire the tet-racycline-resistance gene from tet-positive microbes.
