The clinical effectiveness of a new flossing device, the Floss Plus easy flosser, in reducing interproximal plaque and interproximal gingival inflammation was compared to the effectiveness of hand-held floss. The first phase studied 36 dental students while the second studied 26 adult patients undergoing supportive periodontal treatment. In both phases, the subjects were divided into two groups. One group used the flossing device, while the second group used hand-held floss. The Gingival Index and Plaque Index were taken at baseline, 1 week, and 6 weeks. All groups experienced a significant decrease in the amount of interproximal inflammation and plaque, regardless of which flossing method was used. There was no statistically significant difference between the two flossing methods in the reduction of interproximal inflammation or plaque. These results indicated that the Floss Plus easy flosser is as effective as hand-held floss in reducing interproximal plaque and gingivitis. The use of this aid may benefit those patients who lack the dexterity for hand-held floss or who find flossing cumbersome.