In Vitro evaluation of the antibacterial and remineralization efficacy of pediatric toothpastes with different compositions

Aim: In our study, it was aimed to evaluate in vitro the antibacterial and remineralization efficacy of five pediatric toothpastes formulated with different active ingredients. Materials and Methods: In our study, the toothpastes evaluated included Kids Ozon (containing 1000 ppm fluoride, ozone, and propolis), Oral-B Pro-Kids (containing 1000 ppm fluoride), Dentiste Junior Postbiotics (formulated with 1000 ppm fluoride and postbiotic components), Curasept Biosmalto (including 1000 ppm fluoride and hydroxyapatite), and Zubio (a fluoride-free toothpaste containing hydroxyapatite). To assess remineralization efficacy, 48 specimens obtained from extracted third permanent molars were subjected to baseline microhardness measurement. The samples were then distributed into six groups: five experimental groups corresponding to the respective toothpastes, and one negative control group, each comprising eight samples. Following a 4-day immersion in a demineralizing solution, microhardness was remeasured. Subsequently, a 14-day pH-cycling protocol was applied, during which the toothpastes were administered twice daily, and all specimens were maintained at 37°C. Upon completion of the cycle, final microhardness measurements were performed and data were analyzed statistically. For the antibacterial evaluation, the agar diffusion method was employed using Streptococcus mutans, Lactobacillus acidophilus, Enterococcus faecalis, and Candida albicans strains. After inoculating the agar media, wells were prepared and filled with the respective toothpaste samples, followed by incubation under standardized conditions. Inhibition zones were then measured in millimeters and subjected to statistical evaluation. Results: In our study, all tested toothpaste formulations demonstrated statistically significant remineralization of initial enamel carious lesions (p<0,05). When surface microhardness values after the remineralization phase were compared, the following descending order was observed: Kids Ozon> Dentiste Junior Postbiotics> Curasept Biosmalto> Zubio> Oral-B Pro-Kids> negative control. However, intergroup comparisons of microhardness values revealed no statistically significant differences among the toothpaste groups (p>0,05). In the antibacterial assessment, all toothpaste formulations produced inhibition zones against each tested microbial strain. With respect to Streptococcus mutans, Curasept Biosmalto exhibited a significantly larger inhibition zone compared only to the Kids Ozon group (p<0,05). Although Curasept Biosmalto showed relatively higher antibacterial activity compared to other formulations, the differences were not statistically significant (p>0,05). For the other tested strains, namely Lactobacillus acidophilus, Enterococcus faecalis and Candida albicans, no significant differences in antibacterial efficacy were observed among the toothpaste groups (p>0.05). When total antibacterial effectiveness across all microorganisms was considered, the ranking was as follows: Curasept Biosmalto> Oral-B Pro-Kids> Dentiste Junior Postbiotics> Zubio> Kids Ozon. Curasept Biosmalto exhibited statistically greater total antibacterial efficacy than Kids Ozon (p<0,05), whereas differences among the remaining toothpaste groups were not found to be statistically significant (p>0,05). Conclusion: All toothpaste formulations included in our study were found to exhibit remineralization potential on initial enamel carious lesions and demonstrated antibacterial activity under in vitro conditions. However, to establish their clinical effectiveness against dental caries in children, further long-term clinical trials with extended follow-up are warranted. Key Words: Antibacterial Efficacy, Caries, Remineralization, Toothpaste