Identification of oral bacteria on titanium implant surfaces by 16S rDNA sequencing

Objective: To characterize the profile of microbial communities colonizing titanium implants with different surface treatments after exposure to the oral environment at the genus or higher taxonomic level. Material and methods: Sixteen titanium disks, machined or sandblasted large-grit and acid-etched (SLA), were mounted on removable intraoral splints worn by four patients. After 24 h of intraoral exposure, biofilm samples were collected from disks and supra/ subgingival teeth areas. The 16S rDNA genes from each sample were amplified, sequenced with the Miseq Illumina instrument and analyzed. Results: A total of 29 genera and seven more inclusive taxa, representing the phyla Firmicutes, Proteobacteria, Fusobacteria, Bacteroidetes, Actinobacteria and candidate division TM7 were identified in both titanium surfaces and teeth. No differences were found in relation to the operational taxonomic units (OTUs) and microbial diversity, assessed by Chao 1 and Shannon indices, when comparing SLA and machined titanium surfaces. Conclusions: Machined and SLA surfaces are colonized by similar numbers of prokaryotic OTUs after 24 h of exposure to the oral environment. Higher complexity of the titanium surface topography in the initial phase of biofilm maturation does not seem to significantly influence the colonizing microbiota.