Moran is correct in that this case was almost certainly not caused by the dental procedure 10 weeks previous to symptoms. It is possible that the bacteremia causing the infection in this patient occurred while brushing with a mechanical toothbrush; but, it is also possible that the bacteremia occurred from eating a meal, chewing gum, or even "randomly." In the month before symptoms developed, this patient probably had 510 minutes of exposure to bacteremia from chewing and 4740 minutes of exposure from random bacteremias, but only 120 minutes from brushing.1 While the magnitude and intensity of brushing bacteremias may be greater than from random and chewing bacteremias, the time of exposure to bacteremia was, thus, over 40 times greater from random and chewing than from brushing.
Moran's letter brings up an interesting paradox: brushing and flossing can cause bacteremias in patients with gingival inflammation, but the best way to
Wahl MJ. Myths of Dental-Induced Endocarditis-Reply. Arch Intern Med. 1994;154(18):2114. doi:10.1001/archinte.1994.00420180123021