Methods: Oral biofilm samples collected from healthy subjects and periodontitis patients were subjected to qualitative and quantitative analyses for selected antibiotic resistance determinants using PCR.
Results: The prevalence of tet(Q), tet(M), cfxA, and blaTEM is very high both in the patient and the healthy subject groups with a tendency of higher value in the patient group, with an exception of erm(F), which was more prevalent in the healthy group. The two extended spectrum β-lactam (ESBL) resistance determinants, blaSHV and blaTEM showed a dramatic difference, as blaTEM was present in all the samples, and blaSHV was not found at all. The aacA-aphD, vanA, and mecA genes were rarely detected, suggesting that these are not common in oral bacteria. A quantitative PCR analysis showed that the relative amount of resistance determinants present in oral biofilms of the patient group was much greater than that of the healthy group, exhibiting 17, 13, 145, and 3 folds increase for tet(Q), tet(M), erm(F), and cfxA, respectively.
Conclusions: The results of this study suggest that the oral antibiotic resistome is more diverse and abundant in periodontitis patients than in healthy subjects, suggesting that there is a difference in the diversity and distribution of the antibiotic resistance in oral biofilms associated with health and disease.