Aim & Objective: The purpose of this crossover design, randomised controlled clinical trial was to assess the effect of 0.2% chlorhexidine gluconate and 1.5% hydrogen peroxide mouthwash on mature and newly formed plaque.

Materials and Method: Forty-two patients having gingival index score and plaque index score of ≥1 were included in the study. Selected patients were randomly divided into three groups by using chit method. Gingival index score and plaque index score were recorded at each visit using two-tone plaque disclosing solution and respective mouthwash were given to each group and scaling was done as planned. After a certain period of time crossover was done between the test groups and same procedure was repeated.

Results: On intergroup comparison for gingival and plaque index scores at different time intervals between Group B (0.2 % chlorhexidine gluconate) and Group C (1.5% hydrogen peroxide mouthwash) significant difference was observed on newly formed plaque before crossover and at time intervals after crossover i.e., on both mature plaque and newly formed plaque