Bacterial colonization of oral implants from nondental sources

Implants showing signs of peri-implantitis harbor a microbiota similar to that of periodontitis-affected teeth. This case report describes the subgingival microbiota of a 45-year-old female with advanced periodontitis before and after complete edentulation and reconstruction with dental implants. A 3-month healing period post extraction passed before implants were placed using a two-stage submerged implant protocol. At 4- to 6-month recall visits after definitive prosthetic reconstruction, some implant sites showed bleeding on probing and localized mucositis. Microbiological culture of three inflamed peri-implant sites showed an almost identical spectrum of pathogens, including Porphyromonas gingivalis, Tannerella forsythia, and other major pathogenic bacteria characteristic of aggressive periodontitis. As natural teeth were absent for 8 months, this case report suggests that periodontal pathogens can be retained for a prolonged period of time in nondental sites, from where they can later colonize and compromise the health of dental implants. The therapeutic implications of this finding are discussed.