Evaluation of the Effectiveness of a Mouthwash Containing Spilanthol and Cannabidiol on Improving Oral Health in Patients with Gingivitis—Clinical Trial

<b>Background/Objectives</b>: Plaque-associated gingivitis is widely regarded as a local inflammatory condition initiated by the accumulation of a non-specific dental biofilm in the interaction with the host immune system. The initial symptom noticed by the patient is bleeding gums. The use of mouthwash can serve to supplement mechanotherapy. However, there is an increasing interest in mouthwashes comprising natural ingredients, including cannabidiol (CBD) and spilanthol. The objective of this study was to evaluate the effect of an oral rinse containing spilanthol and CBD oil compared to a rinse containing tea tree oil on the oral microbiota and the values of selected oral status indicators in patients with gingivitis. <b>Methods</b>: The study included 40 patients treated with a rinse containing tea tree oil (TTO)/TTO + spilanthol + CBD for a period of 42 days. Patients rinsed their mouth twice daily for 30 s. The patients' oral microbiome was assessed before and after treatment, and bleeding on probing (BOP) and approximal plaque index (API) were assessed. The study was double-blind. <b>Results</b>: API and BOP were reduced in all groups, both the test and control. The most significant decrease in baseline BOP-1 scores was observed in test groups A and D (<i>p</i> = 0.005062 and <i>p</i> = 0.005062, respectively). A significant difference in API improvement was observed between the initial and final visits in the test (A, D) and control (B, C) groups (<i>p</i> = 0.012516, <i>p</i> = 0.005062, <i>p</i> = 0.004028, <i>p</i> = 0.003172, respectively). <b>Conclusions</b>: Firstly, the use of a mouthwash containing cannabidiol (CBD) and spilanthol was demonstrated to be efficacious in the maintenance of oral microbiota homeostasis. Secondly, the combination of TTO with spilanthol and CBD in the rinse was shown to result in a more significant reduction in selected oral health parameters (BOP and API) and anti-inflammatory effects when compared to a rinse with TTO alone. It should be noted that this is a pilot study and will continue.