Table 1.

In vitro susceptibilities of isolates to penicillin, ceftriaxone, and vancomycin by Etest

Microorganisms (no. of strains [n = 168])	MIC50/MIC90 (mg/liter) valuesa (MIC range) of:
	Penicillin	Ceftriaxone	Vancomycin
Mitis group (n = 92)	0.094/1 (0.007–4)	0.125/1 (0.007–2)	0.5/1 (0.125–1)
Bovis group (n = 54)	0.094/0.125 (0.007–0.25)	0.125/0.25 (0.03–0.5)	0.38/0.5 (0.25–1)
Anginosus group (n = 10)	0.06/0.125 (0.007–0.5)	0.25/0.5 (0.015–1)	1/1.5 (0.5–1.5)
Mutans group (n = 8)	0.015–0.047	0.03–0.125	0.5–1.5
Salivarius group (n = 4)	0.03–0.5	0.015–1	0.25–1

^aResults are expressed as a range when there were fewer than 10 isolates.