Objective: The aim of this study was to evaluate the antibacterial effect of an experimental bis-acrylic temporary crown and bridge material containing 0.5wt% silver-zinc zeolite antimicrobial agent (EXP+Z). Methods: Assessment of antibacterial effect was conducted according to a modified AATCC 100 method. Inhibition of bacterial growth was compared between a control (EXP) and EXP+Z. A cariogenic bacteria Streptococcus mutans was inoculated onto the surface of the specimens (38x38x1mm, n=3). The bacterial colony forming units (CFU) was counted at zero contact time (t=0) and after 24 hours (t=24 hr) of incubation at 37 °C. The percent of bacterial reduction was calculated. Results: Test data were given in the following table:
|
[S. mutans] t=0 (CFUx102) |
[S. mutans] t=24 hr (CFUx102) |
Bacterial Reduction (%) |
|
|
EXP |
1633±322a* |
6633±2303a |
-305.9±122.3a |
|
EXP+Z |
1600±200a |
167±237b |
90.5±13.0b |
* Means with the same letters within the same column are not statistically different (T-test, p<0.05).
At zero contact time the CFU’s of both EXP and EXP+Z were not significantly different. After 24 hours the CFU of the EXP increased significantly with a bacterial growth of more than 300% indicating no inhibition of bacterial growth. On the contrary, the EXP+Z had a much lower CFU after 24 hours with a bacterial reduction of more than 90% indicating strong inhibition of bacterial growth. Conclusion: This study demonstrated that the EXP+Z had a significantly larger inhibitory effect against S. mutans than the control EXP, indicating that the silver-zinc zeolite is an effective antimicrobial agent when incorporated into a bis-acrylic temporary crown and bridge material.