The effect of magnolia bark extract (MBE) on different variables related to caries and
gingivitis administered daily through a
sugar-free
chewing gum was evaluated. The study was performed with healthy adult volunteers at high risk for caries as a randomized double-blind interventional study. 120 subjects with a salivary mutans streptococci (MS) concentration ≥10(5) CFU/ml and presence of
bleeding on probing >25% were enrolled and divided into three groups: magnolia,
xylitol and control. The study design included examinations at baseline, after 7 days, after 30 days of gum use and 7 days after the end of gum use. Plaque pH was assessed using the strip method following a
sucrose challenge. Area under the curve (AUC(5.7) and AUC(6.2)) was recorded. Whole saliva was collected and the number of salivary MS (CFU/ml) was counted.
Bleeding on probing was recorded as a proxy of
dental plaque. Data were analyzed using ANOVA repeated measures. Magnolia gum significantly reduced plaque acidogenicity, MS salivary concentration and gingival
bleeding compared to
xylitol and control gums. Subjects from the magnolia and
xylitol groups showed both MS concentration (p = 0.01 and 0.06, respectively) and AUC(5.7) (p = 0.01 and 0.04, respectively) to be significantly lower compared to baseline. Thirty-day use of a
chewing gum containing MBE showed beneficial effects on oral health, including reduction of salivary MS, plaque acidogenicity and
bleeding on probing.