Figure 3 .
RE-PCR using DNA from P. gingivalis (PG) standards and saliva samples. A) DNA standards obtained from PG samples containing 5.0 x 103 - 106 CFU/mL established minimum threshold (CT) and saturation (CS) cycles; (high concentration) 5/0 x 106 CFU/mL CT = C15, CS = C35; (low) 5.0 x 136 CFU/mL , CT = C30, CS = 55. B) RE-PCR at C30 (at low concentration CT = C30, below high concentration CS = C35) revealed strong, positive correlations (R2 = 0.8507) between signal band intensity (SBI) and CFU/mL. C) RE-PCR using DNA extractions from all saliva samples revealed (n = 10/56 had elevated PG levels. Plotting the PG-positive sample SBI (*) with the DNA standards revealed samples with moderate to very high concentrations; Very high (n = 4), high risk (n = 4), moderate (n = 2). No significant differences in gender (not shown) between PG-positive and overall sample demographics were noted, however 90% (n = 9/10) of the PG-positive samples came from Minority patients, which was significantly different than in the overall sample (64.9%) (X2 = 17.921, d.f. = 1; p < 0.0001; M = minority, W = white). In addition, the ages of PG-positive patients were not found to significantly different than those of the study sample (p = 0.05).
Davis et al. BMC Oral Health 2012 12:34 doi:10.1186/1472-6831-12-34