measuring chlorhexidine tooth staining and efficacy of hydrogen peroxide mouthwash in common whitening procedures

Background: chlorhexidine (chx) mouthwash exerts a broad antibacterial spectrum against gram-positive, gram-negative bacteria, and yeasts but is not without its adverse effects, with staining being a prevalent side effect. this study aimed to determine the extent of discoloration induced by chx mouthwash and investigate the potential impact of hydrogen peroxide mouthwash in mitigating this staining effect.method: this study was a double-blind, randomized two group parallel experiment, using a 14-day non-brushing half-mouth model. patients with mild to moderate gingivitis requiring treatment with chlorhexidine mouthwash were referred to the periodontology clinic of urmia university of medical sciences. the test group was randomly assigned to the mixed 0.12% chx and 1.5% h2o2 mouthrinse, whereas the control group used 0.12% chx. the patients received scaling and polishing 2 weeks prior to the experiment and then rinsed with the allocated mouthrinses twice daily for 2 weeks. the extent and intensity of stain scores were evaluated and recorded by a calibrated investigator.results: thirty subjects completed the study (chx + h2o2 n=15/chx n = 15). there were more females than males in both groups (females: chx: 60%, chx + h2o2: 53.3%) with a mean age of 21.3 ± 2.3 years old. a significant decrease (mean ± sd) in staining scores was observed in both the gingival (0.245 ± 0.35 vs. 0.694 ± 0.50, p=0.001) and body (0.178 ± 0.32 vs. 0.501 ± 0.48, p=0.001) regions of the chx/h2o2 group compared to the chx group.  however, the extent of staining did not differ significantly (chx 0.61 ± 0.34 vs. chx + h2o2 0.62 ± 0.31, p = 0.938) between groups. a significant reduction in staining extent was also observed in both the gingival (0.311 ± 0.43 vs. 1.056 ± 0.87, p=0.001) and body (0.189 ± 0.33 vs. 0.656 ± 0.74, p=0.001) regions of the chx/h2o2 group compared to the chx group. conclusions: in the absence of oral hygiene practice, the mixed chx + h2o2 mouthrinse was slightly superior in reducing stain scores and stain with chx alone.