Dental care as a risk factor for transfusion transmissible infections in blood donors: a systematic review and meta-analysis.

Background and Objectives: The deferral policy for blood donation after dental care is based on the precautionary principle. The aim of this systematic review is to give an overview of the scientific evidence concerning the risk of transfusion transmissible infections (TTIs) after dental care.
Materials and Methods: Four databases were searched: Medline, the Cochrane Library, Embase and Web of Science. Screening was independently performed by two reviewers. The quality of evidence was evaluated using the Grades of Recommendation, Assessment, Development and Evaluation principle. A meta-analysis was performed to assess the association between dental treatment and TTI markers.
Results: A total of 22 studies were included. Meta-analysis of 16 studies showed an increased association of TTIs with dental treatment, however with large heterogeneity. Subgroup analysis revealed a significant increased association of hepatitis B virus (HBV) with dental treatment [odds ratio 1.79, 95% confidence interval (1.48; 2.18)]. There was conflicting evidence concerning the risk of hepatitis C virus (HCV). One study could not demonstrate a statistically significant increased association of human T-lymphotropic virus type I with dental treatment. Three studies showed a significant increased association of HCV with tooth extraction [odds ratio 1.48, 95% confidence interval (1.11; 1.97)]. Finally, there is conflicting evidence concerning the risk of HBV or HCV after dental cleaning. One study could not demonstrate an association between HIV and dental cleaning. All evidence is of very low certainty and results cannot be considered precise.
Conclusion: Studies of high quality concerning the risk of TTI after dental care in blood donors are scarce. An association of HBV after dental treatment and HCV after tooth extraction was demonstrated but evidence is of very low certainty. The currently identified studies are of too low certainty to make any suggestions regarding the value of deferral or deferral times.