Aim: To compare the potential efficacy of two prototype chewing gums in extrinsic stain removal on natural teeth. Setting: Dental school clinics. Design: Double-blind, two groups, parallel design. Participants: 76 adult volunteers (32m, 44f, mean age: 20.6 years old). Methods: Oral hard and soft tissue health was examined. The subjects were randomly assigned to use either Product A (without active ingredients) or Product B (with active ingredients). Each subject was asked to brush their teeth for one minute twice daily (mornings and nights) and chew the gums supplied for 15 min (2 dragees each time), three times daily, once after each meal (breakfast, lunch and dinner) for the entire four-week duration. Dental stain assessment was made on the 12 incisors using the Lobene Stain Index (LSI). Results: The overall difference between the stain scores after 4-weeks' use of the chewing gums was statistically significant (p<0.01) for both test Product A (10.84) and Product B (7.77) with regard to the mean baseline stain scores (21.57). This difference represented a 48% reduction in stain scores for those subjects using Product A, while the reduction was 64% for the subjects using Product B. Conclusions: The results of this in vivo study suggest that chewing gums with and without active ingredients have potential effect on stain removal after regular use for one month.