TABLE 1.
Reduction of metabolic activity after exposure to antibiotics at different concentrations and incubation times
| Time and dilution | % reduction of metabolic activity (mean ± SD) after exposure toa: |
||||
|---|---|---|---|---|---|
| CHX | MTZ | AMX | AZM | AMX-MTZ | |
| 12 h | |||||
| 1:1 | 94.2 ± 1.2 | 40.8 ± 2.6 | 90.4 ± 1.9 | 84.9 ± 7.7 | 93.4 ± 0.5 |
| 1:3 | 22.0 ± 17.4 | 37.3 ± 20.2 | 48.4 ± 32.4 | 71.5 ± 33.4 | |
| 1:9 | 18.5 ± 7.3 | 13.0 ± 32.5 | 21.6 ± 37.4 | 77.4 ± 13.5 | |
| 1:27 | 14.5 ± 9.4 | 0.4 ± 32.0 | −0.5 ± 5.7 | 67.3 ± 25.1 | |
| 24 h | |||||
| 1:1 | 94.8 ± 0.6 | 53.7 ± 3.3 | 64.0 ± 31.8 | 58.6 ± 28.8 | 60.8 ± 46.1 |
| 1:3 | 37.7 ± 8.7 | 37.8 ± 27.2 | 33.8 ± 15.5 | 69.3 ± 23.6 | |
| 1:9 | 23.8 ± 3.4 | 8.5 ± 9.2 | 21.5 ± 7.9 | 56.9 ± 45.6 | |
| 1:27 | 31.0 ± 8.1 | 25.3 ± 10.3 | 13.3 ± 6.4 | 16.0 ± 12.9 | |
| 36 h | |||||
| 1:1 | 95.3 ± 0.2 | 40.7 ± 18.6 | 93.7 ± 0.2 | 90.1 ± 5.4 | 94.3 ± 0.2 |
| 1:3 | 20.6 ± 42.2 | 88.8 ± 5.5 | 50.4 ± 60.7 | 92.5 ± 0.4 | |
| 1:9 | 39.7 ± 9.7 | 43.7 ± 11.8 | 13.0 ± 6.4 | 82.5 ± 2.5 | |
| 1:27 | 12.0 ± 16.4 | 29.8 ± 11.4 | 17.3 ± 7.0 | 84.1 ± 4.6 | |
a
CHX, chlorhexidine; MTZ, metronidazole; AMX, amoxicillin; AZM, azithromycin; SD, standard deviation.