Abstract
Dental implants may share both severe infection and incomplete osseointegration in the absence of obvious clinical signs of infection. While microbiological data have been collected on peri-implant infections, no previous studies have investigated microbiologically incompletely osseointegrated implants. This paper presents microbiological and scanning electron microscopy observations on 30 implants showing incomplete osseointegration. All the 30 implants were colonised by bacterial species that are not commonly isolated from the human oral cavity and periodontium. The morphological analysis showed that bacterial microcolonies and biofilms were present on the surface of all implants.