Silver Oxide Nanoparticles Against Oral Protozoa Targeting Entamoeba gingivalis and Trichomonas tenax in Patients with Periapical Lesions and their Association with Interleukin-6

Abstract

Background: Oral protozoa are measured as etiological agents around the apices of the teeth.

Objective: The present study targeted to assess the connotation of Entamoeba gingivalis and Trichomonas tenax with the levels of salivary interleukin IL- 6 in patients with periapical lesions. The anti-parasitic potential of silver oxide nanoparticles (Ag₂O- NPs) was also investigated in relation to these protozoan species.

Methodology: The cross-sectional study was conducted at the laboratories of the University of Misan, Iraq, and at some specialized clinics, from Nov. 2025 to April 2026. The study comprised 60 patients with clinically identified periapical lesions and 20 individuals without periapical lesions as controls. Unstimulated saliva samples were collected from all participants. The occurrence of Entamoeba gingivalis and Trichomonas tenax was assessed, salivary IL-6 levels were measured, and Ag₂O nanoparticles were synthesized, characterized, and evaluated in vitro towards the isolated protozoa. Sixty unstimulated saliva samples were collected from periapical lesion patients and 20 with no periapical lesion as controls. The prevalence of Entamoeba gingivalis and Trichomonas tenax was measured, and salivary levels of IL- 6 were determined. The physicochemical properties of Ag₂O-NPs were analysed by X -ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, dynamic light scattering, and zeta potential analysis. The anti-parasitic potential of Ag₂O- NPs was assessed against oral parasites at 25, 50, and 100 μg/ml concentrations of the nanoparticles following 2, 6, and 24 h of incubation.

Results: The prevalence rates of Entamoeba gingivalis among patients and controls were 81.7 % and 45%, respectively, while those of Trichomonas tenax were 70.0 % and 25.0% cases. Both protozoa presented significant relations with periapical lesions. Salivary levels of IL- 6 were significantly higher in parasite-positive patients compared to parasite-negative controls; median levels of IL-6 were 30.34 pg/ml (Positive E.g.) versus 12.02 pg/ml for those who were negative for the parasite. Likewise, for Trichomonas tenax positive participants, median levels of IL-6 were 33.41 pg/ml as compared to 14.50 pg /ml for Trichomonas tenax negative participants. Ag₂O- NPs were found to possess crystalline structures with a surface charge and polydispersity and showed significant anti-protozoan activity. At 50 and 100 μg/ml concentrations of Ag₂O- NPs, no trophozoites were observed after 24 hours of exposure.

Conclusion: An association was observed between the presence of oral parasites and increased levels of salivary IL- 6. Ag₂O- NPs displayed significant anti-protozoan activity in vitro.

Bangladesh Journal of Infectious Diseases, June 2026;13(1):262-270