RESUMO
OBJECTIVE: The purpose of this study was to quantify nine selected cariogenic bacteria in plaque from sound root surfaces and initial carious root lesions using TaqMan PCR and to analyse a putative dependence on the kind of initial periodontal treatment. MATERIAL AND METHODS: Fifty-four subjects with generalized chronic periodontitis were randomly allocated to one of the following initial periodontal therapies: full-mouth disinfection, full-mouth scaling and root planing or scaling and root planing within 7 days. Plaque samples were taken before and after periodontal treatment and analysed by TaqMan PCR. RESULTS: The quantity of the cariogenic bacteria Actinomyces spp., Streptococcus mutans, Streptococcus sobrinus, Lactobacilllus spp., Rothia dentocariosa, Parvimonas micra, Propionibacterium acnes and Neisseria mucosa were significantly higher, while the quantity of Veillonella parvula was significantly lower on initial carious lesions than on the sound surfaces both before and after periodontal therapy. No significant differences could be found in any of the tested bacteria except P. micra on initial carious lesions and sound surfaces for both examinations between the groups. CONCLUSION: All the nine species analysed were found to be present in initial carious root lesions as well as sound root surfaces but in different quantities, independent of the different periodontal therapies.
