The antibacterial effect of silver, zinc-oxide and combination of silver/ zinc oxide nanoparticles coating of orthodontic brackets (an in vitro study)

Table 2 Group statistics for colony count of L. acidophilus at two-time intervals

Brackets groups	Colony Count of L. acidophilus
Brackets groups	T1	T2
Control	65.00 ± 11.40	71.25 ± 11.22
Ag	24.69 ± 13.68^a	26.25 ± 10.55^a
ZnO	46.25 ± 12.60^{a, b}	48.75 ± 11.83 ^{a, b}
Ag/ZnO	12.81 ± 15.07^{a, b, c}	13.13 ± 14.92 ^{a, b, c}

T1: test after coating, T2: after 3 months
Data expressed as mean ± S.D%. (n = 12). Data were analysed using ANOVA followed by Post Hoc pairwise comparisons. Statistically significant at ^aP-value < 0.05 versus control, ^bP-value < 0.05 versus Ag-group, ^CP-value < 0.05 versus ZnO-group