| Background. Despite epidemiological and laboratory evidence for the causal association between variant Creutzfeldt-Jakob disease and Bovine Spongiform Encephalopathy (BSE), bovine origin graft materials are widely used during dental surgical procedures. The aim of this study is to assess the risk of BSE transmission through bovine bone substitutes by a systematic literature review.;Methods. A systematic review was performed on studies in MEDLINE published in English between 1998 and 2010 to evaluate the risk of BSE transmission from bovine-derived bone graft materials.;Results. Search strategy identified 1912 potentially relevant studies, and 25 studies were included in the final analysis. Wide distribution of PrPSc and BSE infectivity was detected in peripheral nerve system and other tissues including bone marrow and serum samples. Low levels of prion infectivity in non-central nervous system (CNS) tissues appeared increased with contamination by CNS tissues with potentially high prion infectivity during bovine slaughtering and carcass handling process, and washing facilities could not eliminate the CNS tissue contamination occurred on bovine carcasses, operatives, and abattoir machinery. Proteins were detected in some deproteinized anorganic bovine bone substitutes, and inactivation of BSE prion infectivity by biomaterial manufacturing processes has not been proven. Additionally, PrPSc, a current surrogate marker for transmissible spongiform encephalopathies (TSE) infectivity including BSE, was not always detected in tissues containing BSE infectivity, and inconsistent results among different PrPSc detection methods was not uncommon.;Conclusion. This review indicates that bovine-derived graft biomaterials carry a risk of prion transmission to patients. |
