Some of you may be unaware that in 2009 the AAOS published a statement calling for universal AP prior to oral procedures for those with a prosthetic joint. This statement was published on the AAOS website with no input from the ADA. It, essentially, dismantled the joint policy on the issue by the ADA/AAOS. The ADA on their website says there is no science to support this decision but at this time dentists are advised to communicate with the client's orthopedist for guidance. Most orthopedists will likely prescribe AP, although there is absolutely no evidence it is effective to prevent PJI. A rigorous case control study published by Mayo Clinic revealed that dental procedures were not a source for joint infection in their study and also that the drugs in the ADA/AAOS regimen had no evidence of efficiency for preventing PJI (Berberi et al 2010). The UK stopped all AP prior to oral procedures and report no increase in infective endocarditis. A recent study in USA reports same results, no increase in IE when AHA revised the guidelines in 2007. Someone should look at the prevalence of PJI comparing the prevalence between 1997 (when joint guidelines were published and called for AP only in high risk population for joint infection) up to 2008 and the prevalence from 2009 to 2012. That data would be interesting to see. Canada has a group that tracks PJI so their data could be used to look at the impact of the 2009 statement (positive or negative).