effect of 20-ppm ozone and 1% chlorhexidine gels on plaque index and streptococcus mutans counts in the dental plaque in 6–12-year-old children: a randomized, double-blind clinical trial

Background. one of the methods to control dental caries is to use ozone. since it is difficult for children to use mouthwashes, the present study aimed to evaluate 20-ppm zone and 1% chlorhexidine (chx) gels’ effects on the plaque index and streptococcus mutans counts in 6–12-year-old children. methods. in the present double-blind clinical trial, 165 children, 6–12 years of age, referring to the department of pediatric dentistry, tabriz faculty of dentistry, were selected based on inclusion and exclusion criteria and randomly assigned to three groups: ozone gel, chx gel, and control. the subjects were instructed to place an adequate amount of the gels on all the surfaces of their teeth with one clean finger. the patients and evaluators were blinded to the study groups. the plaque index and s. mutans counts in plaque samples were determined before intervention and three weeks after intervention on the buccal surface of the most posterior maxillary tooth (left or right). s. mutans counts were determined by culture. stata software version 14 was used for statistical analyses using wilcoxon, kruskal-wallis, and post hoc dum tests. statistical significance was defined at p<0.05. results. the 20-ppm ozone and 1% chx gels significantly decreased dental plaque compared to the control group (p<0.05), and their effects were similar (p>0.05). these gels significantly decreased the colonies and bacterial counts of s. mutans (p<0.05). conclusion. the performance of 20-ppm ozone gel in decreasing the dental plaque and s. mutans counts was similar to 1% chx gel.