Title: The implant infection paradox: why do some succeed when others fail? Opinion and discussion paper

Author: C Yue, B Zhao, Y Ren, R Kuijer, HC van der Mei, HJ Busscher, ETJ Rochford

Address: University of Groningen, University Medical Center Groningen, Department of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands

E-mail: e.rochford at umcg.nl

Key Words: Implant infection, immune responses, host, pathogens, infection risk, biofilms.

Publication date: June 5th 2015

Abstract: Biomaterial-implants are frequently used to restore function and form of human anatomy. However, the presence of implanted biomaterials dramatically elevates infection risk. Paradoxically, dental-implants placed in a bacteria-laden milieu experience moderate failure-rates, due to infection (0.0-1.1 %), similar to the ones of joint-arthroplasties placed in a near-sterile environment (0.1-1.3 %). Transcutaneous bone-fixation pins breach the immune-barrier of the epidermis, exposing underlying sterile-tissue to an unsterile external environment. In contrast to dental-implants, also placed in a highly unsterile environment, these pins give rise to relatively high infection-associated failure-rates of up to 23.0 %. Herein, we attempt to identify causes as to why dental-implants so often succeed, where others fail. The major part of all implants considered are metal-made, with similar surface-finishes. Material choice was therefore discarded as underlying the paradox. Antimicrobial activity of saliva has also been suggested as a cause for the success of dental-implants, but was discarded because saliva is the implant-site-fluid from which viable bacteria adhere. Crevicular fluid was discarded as it is largely analogous to serum. Instead, we attribute the relative success of dental-implants to (1) ability of oral tissues to heal rapidly in the continuous presence of commensal bacteria and opportunistic pathogens, and (2) tolerance of the oral immune-system. Inability of local tissue to adhere, spread and grow in presence of bacteria and an intolerant immune-system are identified as the likely main causes explaining the susceptibility of other implants to infection-associated failure. In conclusion, it is the authors’ belief that new anti-infection strategies for a wide range of biomaterial-implants may be derived from the relative success of dental-implants.

Article download: Pages 303-313 (PDF file)
DOI: 10.22203/eCM.v029a23