16S rDNA sequencing data of Dutch dental unit water

Dental practises were approached to fill out a questionnaire on the infection control measures in use and to send two types of water sample. Sampling of the dental units had to be performed on the second day of operation in the week to avoid residual effects of biofilm disinfection protocols performed in the weekend. Instructions were given to a-septically sample the units. Only samples, accompanied with a completed questionnaire and returned by regular mail within 2 days were analysed. Samples were processed for heterotrophic plate counts, microbiome sequencing and q-pcr for the presence of bacterial 16S rDNA, fungal 18S rDNA, Legionella spp. and amoeba.