Clinical characteristics of the study groups
GINGIVAL BLEEDING, PLAQUE
Ten volunteers were excluded from the initial sample of 60 participants, leaving 50 subjects separated into two study groups: test group A (n = 24) and test group B (n = 26). The mean ages of the volunteers were 21.87 ± 1.51 and 22.00 ± 3.07, respectively, with a predominance of females in both groups (58.33% and 76.92%, respectively). In the whole-mouth assessment, all the participants had very low levels of bacterial plaque (mean = 6%) and periodontal parameters indicative of health (mean gingival bleeding = 3%, probing depth = 1.75 mm, and absence of clinical attachment loss). No significant differences were detected between the two study groups in any of the clinical parameters recorded (Table 
Clinical characteristics of the study groupsValues indicate means (± standard deviations) and the number of subjects. After applying the Shapiro-Wilk test and determining the non-normal distribution of almost all the clinical variables, the Mann-Whitney U test was used to compare the quantitative clinical variables between the two study groups; the exception was the variable “probing pocket depth” (where the Student’s t-test was applied for independent groups). Fisher´s exact test was used to assess the association of the qualitative variables between the two study groups. A significance level of p < 0.05 was establishedmm, millimetres; SD, standard deviation