Antibacterial effect of MTA, calcium hydroxide, Portland cement, and a new endodontic material

Aim: The antibacterial effects of calcium hydroxide (CH), mineral trioxide aggregate
(MTA), Portland cement (PC), and a new endodontic material (NEM) against various
spp and the mixture of them. Of microorganisms and a mixture of them was assessed
in vitro using the agar diffusion test.
Materials and Methods: A base layer of Petri plates was made using Muller-Hinton
agar. Four cavities were made in agar and filled with fresh mixed materials after 24 h.
The Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus,
Escherichia coli and a mixture of them were seeded by pour plate. The plates were
pre-incubated for 2 h at room temperature followed by incubation at 37°C for 72 h.
The inhibition zones diameters were measured by an independent observer at 24, 48
and 72 h.
Results: The highest mean diameters of growth inhibition zones were found around
CH and NEM. According to one-way ANOVA there was a significant difference
among test groups (p<0.001), while Post Hoc test revealed no significant difference
between the mean zones diameter of CH and NEM, and also between MTA and PC in
all groups.
Conclusion: However, there was significant difference among CH and NEM in
comparison with MTA and PC groups (p<0.001). It appears that NEM was a potent
bacterial growth inhibitor like CH.
Keywords: Antibacterial agent, Calcium hydroxide, Endodontics, Mineral Trioxide
Aggregate, New material.