Efficacy of propolis in 5 natural toothpastes for the inhibition of Streptococcus mutans. In Vitro Study

Abstract

Introduction: Currently, Streptococcus mutans is one of the main etiological agents in the development of dental caries due to its acidogenic and aciduric capacity and its ability to form biofilms on tooth surfaces. In the search for natural alternatives for its control, propolis has demonstrated remarkable antimicrobial properties. Objective: The objective of this study was to evaluate the efficacy of propolis present in five natural toothpastes to determine its capacity to inhibit the growth of Streptococcus mutans bacteria. Methodology: The research evaluated the antimicrobial efficacy of propolis in five natural toothpastes against Streptococcus mutans (ATCC 25175) using an in vitro experimental design. One hundred and twenty samples were taken and divided into six groups of 20 replicates each, in groups G1 to G6. The strain was cultured on blood agar at 0.5 McFarland, and well diffusion tests were performed by incubating it at 37°C with CO₂ (5-8%) for 24 and 48 hours. A pilot test and 20 final replicates were conducted. Growth inhibition zones were measured with a digital vernier caliper and statistically analyzed using ANOVA to identify significant differences, followed by post-hoc tests. This research contributes to the development of more effective natural dental products. Results: These showed that, when comparing groups, incorporating propolis into toothpaste formulations was effective, and its presence inhibited the growth of S. mutans. However, no differences were found in the 24- and 48-hour measurements. Conclusions: The use of natural toothpastes with propolis is an effective alternative for inhibiting S. mutans. However, the geographical origin of the toothpaste affected the final results, with the propolis toothpaste from Ecuador proving to be the best alternative.