Staphylococci may indeed cause acute dental infections

Editor—In their letter Ribeiro and Cousin contend the likelihood of a causal relation between the development of an epidural abscess after root canal treatment and the isolation of Staphylococcus aureus in the report by O'Rourke et al.¹,²

We disagree and support the original proposal of O'Rourke et al because recent studies using both molecular technology and conventional culture techniques indicate conclusively that Staphylococcus spp are not uncommon in dental root canal infections.³,⁴ Furthermore, in a stringent and comprehensive investigation that we are currently conducting on the microflora of endodontically involved teeth, staphylococci were isolated from root canals in eight out of 86 patients (unpublished data). Indeed in two cases, staphylococci were the sole and major isolate from the aseptically opened, infected root canals.

We emphasise, however, that most endodontic infections are polymicrobial in nature. Using the polymerase chain reaction, Munson et al recently found a mean of 17 taxa in endodontic samples and a total of 30 new phylotypes.⁵ Therefore, acute dental infections are still best treated by antimicrobial agents such as penicillin, amoxicillin, clindamycin, and metronidazole, but the possibility of staphylococci causing acute exacerbations or bacteraemias should not be overlooked.