title: Implant-abutment leaking of replace conical connection nobel biocare®implant system. Anin vitrostudy of the microbiological penetration from external environment to implant-abutment space.
abstract: OBJECTIVE
  The aim of our study is to value the microbial contamination in the implant-abutment connections (IAC) of a Nobel Replace Conical Connection implant system [Nobel Biocare®, Vimercate (MB), Italy].
  
  
  METHODS
  To identify the capability of the implant to protect the internal space from the external environment, the passage of genetically modified bacteria across IAC was evaluated. Four Nobel Replace Conical Connection implants (Nobel Biocare®, Vimercate (MB), Italy) were immerged in a bacterial culture for twenty-four hours and then bacteria amount was measured inside and outside IAC with Real-time PCR. Bacterial quantification was performed by Real-Time Polymerase Chain Reaction using the absolute quantification with the standard curve method.
  
  
  RESULTS
  In all tested implants, bacteria were found in the inner side, with a median percentage of 10.9%. The analysis revealed that in both cases (internally and externally), bacteria grew for the first 48 hours but subsequently they started to dye, probably as a consequence of nutrient consumption. Moreover, the difference between outer and inner bacteria concentration was statistically significant at each time point.
  
  
  CONCLUSIONS
  Implant's internal contamination shows that IAC is not sealing. The reported results are similar to those of previous studies carried out on different implant systems. Until now, no IAC has been proven to seal the gap between implant and abutment.
authors.affiliation: Private practice, Turin, Italy.
authors.forename: E
authors.initials: E
authors.lastname: El Haddad
authors.affiliation: Maxillo-Facial and Dental Unit, "Fondazione Cà Granda IRCCS Ospedale Maggiore Policlinico", Milano, Italy.
authors.forename: A B
authors.initials: AB
authors.lastname: Giannì
authors.affiliation: Maxillo-Facial and Dental Unit, "Fondazione Cà Granda IRCCS Ospedale Maggiore Policlinico", Milano, Italy.
authors.forename: G E
authors.initials: GE
authors.lastname: Mancini
authors.affiliation: Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna, Bologna, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Cura
authors.affiliation: Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Carinci
keywords: and perimplantitis; bone resorption; implant-abutment connection; microbiological leakage