Delayed postwash comparison (persistent
effect). The left-hand delayed postwash
bacterial counts were used to determine the
persistent activity of the test preparations. The
logi0 means for chlorhexidine and alcohol treatments
for each exposure time and day are given
in Table 4. The combined delayed postwash
bacterial counts were significantly lower on days
1, 2, and 5 for both treatments when compared
with the left-hand base line counts. The greatest
reduction in bacterial counts was noted on the
5th day. The overall logio means were 4.9943 and
5.4684 for chlorhexidine and alcohol, respectively.
From the split-plot analysis of variance,
the difference between the two treatments was
statistically significant (P < 0.05). At no time
did the delayed postwash bacterial counts approach
the base line level.