Evaluation of the Effectiveness of Nine Brands of Toothpaste on Streptococcus mutans Isolated from the Mouth of Students in Veritas University, Abuja

Dental caries is an infectious microbiological disease of the teeth that end up in the destruction of dental hard tissues. The use of toothpaste has been used to reduce the bacterial load in the mouth because they contain antimicrobial properties such as triclosan, fluoride, and so on. The study aimed to determine the effect of nine brands of toothpaste on Streptococcus mutans isolated from the mouth of students in veritas university. Following the isolation of Streptococcus mutans from samples collected from the mouths of Veritas students’, the antimicrobial activity of different concentrations of the dentifrices was determined by modified agar well diffusion method. In this method, Muller Hinton agar plates were seeded with a loop full of 24-hour cultures of the bacterial isolate. A sterile 8 mm cork-borer was used to cut one central and five wells at equidistance in each of the plates. 0.3 ml of the dentifrice dilutions was introduced into each of the five wells while the same amount of sterile distilled water was introduced into the first well as control. The plates were incubated at 37°C for 24 hours. The antimicrobial activity was evaluated by measuring the diameter of zones of inhibition (in mm). The diameter in which the bacteria were inhibited was indicative of the toothpaste’s antibacterial potential. The zones of inhibition on the growth of the test strain were defined by the location where visible growth had been inhibited. All the plates were made in triplicates and the experiments repeated twice. The result showed that Mentadent-P was the most effective dentifrice with an inhibition zone of 2.8 mm, Pepsodent had inhibition zone of 2.6 mm, Oral B with 2.3 mm, Close up with 2.2 mm, followed by Colgate with a diameter of 1.9 mm, Special Lucky with a diameter of 1.6 mm, Darbur Promise with a diameter of 1.6 mm, Maclean’s with a zone of inhibition of 1.5 mm, and MY- MY with the least effective toothpaste with a zone of inhibition of 1.0 mm in diameter. The results also showed that toothpaste containing fluoride as their main antimicrobial agent proved more effective against streptococcusmutans than other toothpaste not containing fluoride as their main antimicrobial agent.