1- Streptococcus mutans: The results of this study showed that coconut oil had a statistically significant higher inhibitory effect on SM with decrease in number of CFU from 500 to 40 and 53.7 and percentage of reduction 92% and 89.3% at 2 and 24 hours contact period consecutively as shown in (tables (1 & 2) & fig. (1)) and (fig 2 A & B). Also, Nigella sativa oil showed an inhibitory effect on SM after 2 hours contact period with decrease in number of CFU from 500 to 158.3 and …show more content…
2- Candida albicans: Regarding the effect of the tested herbal oils on Candida albicans the results showed that, coconut oil had a statistically significant high inhibitory effect on the organism with decrease in number of CFU from 500 to 62.3 and 63.3 and % of reduction 87.5 and 87.3 %after 2 and 24 hours contact period consecutively (1 & 2) & fig. (1)) and (fig 3 A & B). Meanwhile Nigella sativa oil showed no effect on this organism (1 & 2) & fig. (1)) and (fig 3 C & D). By comparing the antimicrobial effect of these two herbal oils versus our gold standard Chlorhexidine gluconate 0.2% the later showed superior results on all tested microorganisms with decrease in number of CFU from 500 to 2.7, 2, 2 and a % of reduction 99.5, 99.6 and 99.6 % for SM, LB, and Candida species at 2 and 24 hrs. contact period consecutively (table (1& 2) and fig 1).
Table (1): Mean, standard deviation (SD) values and results of comparison between CFU counts in the three groups and the changes within each