Effects of Pine Bark Extract Chewing Gum on Oral Malodor

Pycnogenol^® (PYC) is a standardized bark extract of the French maritime pine tree (Pinus pinaster Aiton).  It has been reported to have antibacterial activity or inhibitory effects on various pathogenic properties of oral bacteria.  The objective of this study is to evaluate the inhibitory effects of chewing gum containing the pine bark extract on oral malodor of the general adult population.

Methods:

Subjects were randomly assigned to the following groups; an experimental group (30 mg PYC intake per day) (n = 11) and a placebo group (n = 10), using the double-blind study method.  The subjects were instructed to chew 2 pieces of PYC gum or placebo gum 6 times daily for 15 min during the intake period (4 weeks).  The levels of volatile sulfur compounds (VSCs), measured by OralChroma^TM (ABIMEDICAL Co., Japan) and tongue-coating score were recorded at baseline, 2 and 4 weeks.  Stimulated saliva samples and tongue coatings were collected and spread onto Brucella blood agar plates containing 0.05% cysteine, 0.12% glutathione and 0.02% lead acetate to cultivate hydrogen sulfide-producing bacteria.

Results:

The level of oral malodor was observed greater than or equal to the threshold level in all subjects at baseline.  The PYC gum group exhibited significant reduction for hydrogen sulfide (H₂S), methyl mercaptan (CH₃SH), dimethyl sulfide [(CH₃)₂S] and total VSCs at 2 weeks after baseline.  Tongue-coating score was significantly lower at 4 weeks in the PYC gum group compared to the placebo gum group.  Furthermore, the number of hydrogen sulfide-producing bacteria in saliva samples decreased at 4 weeks in the PYC gum group.

Conclusion: The results suggest that PYC chewing gum is effective to reduce oral malodor by decreasing the accumulation of tongue coating and the number of hydrogen sulfide-producing bacteria in saliva.