Efficacy of an Anti-Discoloration System (ADS) to Reduce Dental Staining in a 0.12% Chlorhexidine-based Mouthwash

In the first phase, the "immediate" objective and subjective evaluation of dental discoloration by spectroscopic (CIE L*a*b* data analysis with DeltaE evaluation) and questionnaire-based analyses will be recorded. Immediate visual analysis of tooth pigmentation will be evaluated by volunteer him/herself, using a mirror, and by a single dentist soon after the end of each treatment. Participants will indicate the presence/absence of dental pigmentation, and to quantify it with a numeric scale (0= no pigmentation to 10= very strong pigmentation).

These analyses will be performed at baselines and after each 21-days-long cycle of mouthwash.

A wash-out period between the cycles of 21 days will be performed. In the second "late" phase, a long-term subjective evaluation of dental discoloration will be obtained by means of the visual analysis of clinical photograph and new questionnaires. After 6 months from clinical trial (second stage of the study), frontal dental images of volunteers, collected during the first phase, will be printed on photographic paper and, then, visually analyzed, in blind, by the 22 volunteers themselves, as well as by 14 dentists and 13 oral hygienists ad hoc recruited. Dentists and oral hygienists, in particular, will be asked to observe two images of all the 22 subjects, i.e. after treatment with A or B mouthwash, and to answer to the question: "Which picture shows the most pigmented teeth?" Possible answers will be: "A, or B or no difference between the two images". Pigmentation will be also quantified using the numeric scale (0= no pigmentation to 10=strong pigmentation).

The observer will be not instructed in how the color of the teeth should appear in case of CHX pigmentation.