In vivo early plaque formation on pure titanium and ceramic abutments: a comparative microbiological and SEM analysis

A lack of information exists about the influence of different implant abutment materials on bacterial colonization and its role in the development of perimplantar infections. In order to study these aspects, removable acrylic devices, harboring samples of titanium and novel ceramic abutments (Nobel Biocare) were adapted to the molar-premolar region in 2 mandibular quadrants of 4 volunteers. Samples of each material were collected at 6 and 24 h, 7 and 14 days. Samples were observed by scanning electron microscopy and bacterial counts were made by means of ATP detection and direct plate count. The electron micrographs demonstrated that the bacteria colonization was already present after 6 h of presence in the oral cavity. After 24 h, both the materials were covered by several layers of bacterial cells. No differences in microbial colonization were observed between titanium and ceramic samples. The microbiological analysis confirmed the presence of relevant amounts of microbial cells on the tested samples. The maximum of colonization was achieved after 24 h in the oral cavity and the bacterial counts remained constant over the 14 day period. No significant differences were observed between the two materials analyzed in this study. In addition, ATP-bioluminescence technology was demonstrated to be a suitable system to evaluate bacterial colonization in the oral cavity.