In 122 subgingival plaque samples, the positive rates of 16S rDNA, lktA and fap genes by PCR were 84.4%, 75.4% and 50.0% respectively. Different A.

• 12 2份龈下菌斑中Aa 16SrDNA、lktA和fap检测阳性率分别为 84 .；4%25、75