Antibacterial Effect of Iodine‐Based Paste With Silver Nanoparticles Against <i>Enterococcus faecalis</i> : An In Vitro Study

BACKGROUND: Pulpectomy is one of the most common treatments for the rehabilitation and conservation of primary dentition. This procedure requires thorough disinfection of the root canals to eliminate the bacterial load prior to obturation. However, the anatomical complexity of primary root canals limits the complete eradication of certain bacteria, such as Enterococcus faecalis (E. faecalis). Although iodine-based pastes, such as Vitapex, are considered the gold standard for primary root canal fillings due to their excellent clinical outcomes, the extent of their antibacterial efficacy remains unclear. OBJECTIVE: To evaluate the antibacterial efficacy of an iodine-based paste incorporated with silver nanoparticles against E. faecalis. DESIGN: This experimental study employed a comparative, cross-sectional, analytical, and prospective design. METHODS: Silver nanoparticles (AgNPs) were synthesized and chemically characterized prior to incorporation into an iodoform paste (Vitapex). The antibacterial efficacy was subsequently evaluated across three distinct groups: Group 1 (Vitapex), Group 2 (AgNPs), and Group 3 (Vitapex with AgNPs). Experiments were performed in triplicate using the E. faecalis ATCC 29212 strain to measure the zones of inhibition for each group. RESULTS: Significant statistical differences were observed (p = 0.003) in the inhibition zones against E. faecalis. The antibacterial activity of the Vitapex+AgNPs combination (SD 13.93 ± 0.83) was significantly higher than that of Vitapex (SD 10.26 ± 0.88) and AgNPs (SD 11.15 ± 2.40) alone. CONCLUSION: Our results demonstrate that both Vitapex and AgNPs exhibit antibacterial activity against E. faecalis; furthermore, their combined application shows a superior synergistic effect.