Helicobacter pylori in dental plaque - A comparison of different PCR primer sets

This study was designed to compare different primer sets for PCR analysis o f H. pylori in the same series of 40 dental plaque samples. Three pairs of primers, HPU1/HPU2, HP1/HP2, and EHC-U/EHC-L, directed to the urease A gene , 16S rRNA gene, or 860-bp DNA of H. pylori, respectively, were used. Our r esults demonstrate that EHC-L/EHC-U were more specific and sensitive for H. pylori added to saliva or dental plaque than HPU1/HPU2 and HP1/HP2. The de tection rates for H. pylori DNA in dental plaque samples from randomly sele cted adult patients from the Dental Clinic of the University of Ulm were 26 .5% (9/34) for HPU1/HPU2, 78.9% (30/38) for HP1/HP2, and 100% (40/40) for E HC-U/EHC-L (P < 0.001). Nested PCR using primers directed to the 860-bp DNA of H, pylori further confirmed the presence of H. pylori DNA (40/40) in al l these samples. Our results indicate that primers EHC-U/EHC-L are to be re commended for PCR detection of H. pylori in the oral cavity.