Clinical evaluation of residual tetrasodium pyrophosphate released from two different anticalculus flosses

The aim of this study was to compare the residual content of tetrasodium pyrophosphate released by two different anticalculus dental flosses (Reach PP®--entangled polypropylene floss and Reach NT®--texturized nylon) in the oral cavity. Ten healthy individuals (aged between 18 and 30 years) were enrolled in this randomized crossover clinical investigation. Participants received instructions on daily dental flossing and the interventions were randomly performed in 2 different groups (NT or PP) of five individuals each according to the dental flosses. Individuals were instructed to use each dental floss with a total of six slides on the two interproximal aspects of target teeth (3 slides on each interproximal aspect). A washout period of one week was used before start flossing interventions and after each type of dental floss to prevent any bias related to the exposure to any product that contained the active ingredient. Samples were collected by #35 sterilized absorbent paper points from interdental fluid after flossing and assessed by ion chromatography. The levels of residual tetrasodium pyrophosphate were evaluated by means of binomial generalized linear model proportions and canonical link function. Both dental flosses were effective in tetrasodium pyrophosphate release at therapeutic levels in the interdental gingival crevicular fluid for a period of up to 2 h after use. No significant differences were found between both groups (p>0.05). It may be concluded that both material composition and physical structure of the new dental floss did not affect the release or the maintenance of anticalculus agent at therapeutic levels for a period of up to 2 h after single use.