^{*} *Aggregatibacter actinomycetemcomitans (Aa); Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf); Fusobacterium nucleatum (Fn); Prevotella intermedia (Pi); Campylobacter rectus (Cr); Treponema denticola (Td).*

Mean denotes mean CV% from 22 samples tested in triplicate for all primers except

*Aa*, which was derived from the 12 samples that contained measureable

*Aa.* Median denotes the median CV% for the same samples. Correl denotes the rank correlation of the CV% with the total number of bacteria (Universal) or the number of the individual species. A minimum correlation coefficient of ±0.4227 is required for a

*p*<0.05 level of significance.