Biofilm on dental implants: a review of the literature.
OBJECTIVE
The aim of this article was to review the current literature with regard to biofilm formation on dental implants and the influence of surface characteristics (chemistry, surface free energy, and roughness) of dental implant and abutment materials and their design features on biofilm formation and its sequelae.


METHODS
An electronic MEDLINE literature search was conducted of studies published between 1966 and June 2007. The following search terms were used: biofilm and dental implants, biofilm formation/plaque bacterial adhesion and implants, plaque/biofilm and surface characteristics/roughness/surface free energy of titanium dental implants, implant-abutment interface and plaque/biofilm, biofilm and supragingival/subgingival plaque microbiology, biofilm/plaque and implant infection, antibacterial/bacteriostatic titanium, titanium nanocoating/nanopatterning, antimicrobial drug/titanium implant. Both in vitro and in vivo studies were included in this review.


RESULTS
Fifty-three articles were identified in this review process. The articles were categorized with respect to their context on biofilm formation on teeth and dental implant surfaces and with regard to the influence of surface characteristics of implant biomaterials (especially titanium) and design features of implant and abutment components on biofilm formation. The current state of literature is more descriptive, rather than providing strong data that could be analyzed through meta-analysis. Basic research articles on surface modification of titanium were also included in the review to analyze the applications of such studies on the fabrication of implant surfaces that could possibly decrease early bacterial colonization and biofilm formation.


CONCLUSIONS
Increase in surface roughness and surface free energy facilitates biofilm formation on dental implant and abutment surfaces, although this conclusion is derived from largely descriptive literature. Surface chemistry and the design features of the implant-abutment configuration also play a significant role in biofilm formation.
Subramani
Karthikeyan
K
Department of Fixed and Removable Prosthodontics and Dental Material Science, Center for Dental and Oral Medicine and Cranio-Maxillofacial Surgery, University of Zurich, Switzerland. karthikeyan.subramani@lycos.com
Jung
Ronald E
RE
Molenberg
Aart
A
Hammerle
Christoph H F
CH
D001422:Bacterial Adhesion; D018441:Biofilms; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D000044:Dental Abutments; D015921:Dental Implants / Q000382:microbiology*; D003764:Dental Materials / Q000737:chemistry; D003773:Dental Plaque / Q000382:microbiology; D017267:Dental Prosthesis Design; D006801:Humans; D049329:Nanostructures / Q000737:chemistry; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
D020099:Coated Materials, Biocompatible; D015921:Dental Implants; D003764:Dental Materials; D014025:Titanium