ARTICLE INFO Article HistoryBackground and Aim: Reducing the number of pathogenic microorganisms can contribute to reducing the incidence and epidemiology of periodontal diseases. This study aimed to evaluate the clinical effects of Ardox-X active oxygen-containing toothpaste on periodontal indices in patients with at least 1 to 2 implants. Materials and Methods:In this crossover randomized clinical trial, 30 subjects were randomly divided into two groups (n=15). Oral hygiene instructions were delivered to all subjects before the study. Scaling and root planing (SRP) were performed for all subjects. The subjects were instructed to brush with Oral-B toothpaste and toothbrush twice daily for at least two minutes. All subjects returned 10 days later, and the plaque index (PI) and gingival bleeding index (GBI) were measured. The first group received Ardox-X, and the second group received Oral-B toothpaste. Both groups presented after 7 days, and GBI and PI were measured. SRP was performed again, and the plaque was zeroed. Both groups spent the wash-out period for 10 days. Next, the indices were measured again. The Ardox-X group received Oral-B toothpaste and vice versa. After 7 days, both groups returned, and the indices were measured again. T-test was used for statistical analysis. Results: No significant difference was observed in the PI changes between the control (0.88±0.22%) and case (0.83±0.22%) groups (P<0.6). The changes in the GBI were significantly different between the control (3.9±3.4%) and case (1.5±2%) groups (P<0.01). Conclusion:The results of this study showed that Ardox-X toothpaste performs better than the control group (Oral-B) in terms of the GBI.