The changing nature of pyogenic dental infections.

During the years 1978 and 1979 there has been a marked change in the proportion of bacteria isolated from dental infections compared with the ten year period to 1978. There has been a reduction in the proportion of streptococci found and an increase in the proportion of the Gram negative species encountered. There has been a steady decline in the effectiveness of penicillin although this has to some extent been offset by the introduction and widespread use of amoxycillin. The greatest change in antibiotic sensitivity has been the reduction in sensitivity to the tetracyclines.