Prevalence of pathogenic microorganisms in the oral cavity and their sensitivity to some selected dentifrice sold at major markets in Kano Metropolis

Abstract

This study was conducted to determine the incidence of pathogenic microorganisms associated with dental caries and antimicrobial susceptibility test of some common dentifrice sold in Kano metropolis. A total of 50 samples were used in this study. The samples were taken using swab from human oral mucosa. The swabs were inoculated on chocolate agar, blood agar and MacConkey agar incubated at 37⁰C for 24h, as well as Sabouraud’s dextrose agar incubated at room temperature for 48h. Dentifrices were also analyzed for the fluoride, phosphate, nitrite, potassium, chloride, carbonate, sulphate, calcium, sodium, and zinc contents using C: Varian/Cary Winuv method, Acid Base Titration method, Gravimetry, and Air/Acetylene method. Of all the isolates, Streptococcus mutans was the most isolated pathogen with 24(30.38%), followed by Staphylococcus aureus with 23(29.11%), Candida. albicans 14(17.72%), Klebsiella specie 10(12.66%) and Escherichia coli 8(10.13%). Disc diffusion method with ten different dentifrices (code A-J) was tested for their antimicrobial activity against isolated oral pathogens. The samples were tested in triplicate, at full strength, 1:1, 1:2, 1:4, 1:8 and 1:16 dilutions. Inhibition zones were measured in millimeter after 24 hours. All the tested dentifrices demonstrated an antimicrobial activity. Dentifrice A showed the maximum mean zones of inhibition of 26.67, 24.00, 22.27, 19.67 and 18.67 against Klebsiella specie, Escherichia coli, Staphylococcus aureus, Streptococcus mutans and Candida albicans respectively, while dentifrice J showed the least activity of 0.00, 0.00, 0.00, 14.67 and 18.67 respectively against the same organisms. The concentrations of fluoride range between 8.3- 132.3mg/L; phosphate, 45.8-191.8mg/L; nitrite, 11.0mg/L; potassium, 3.2mg/L; chloride, 5.1- 5.6mg/L; carbonate, 8.2-12.8mg/L; sulphate, 0.3-0.9g; calcium, 14.7-16.1mg/L; sodium, 350.6- 418.8mg/L and zinc, 6.2mg/L. In the present study, it has been demonstrated that triclosan- containing dentifrice are more effective in the control of pathogenic microorganisms associated with oral cavity compared to non-triclosan containing dentifrice.

Keywords: Bacteria, Dentifrice, Kano, Oral cavity