Efficacy and Safety of BNP105 in the Treatment of Recurrent Aphthous Stomatitis

Inclusion Criteria: * Ability to confirm voluntary participation and agree to all trial purposes by signing and dating the informed consent forms; * Age greater than or equal to 12 years; * One minor recurrent aphthous stomatitis with onset of symptoms within 48 hours; * Moderate to severe baseline pain, with VAS ≥ 60 mm (EVA scale 0-100 mm). Exclusion Criteria: * Any clinical findings that, in the judgment of the investigator, may interfere with the safety of research participants; * Participants diagnosed with: Behcet's disease, rheumatoid arthritis, systemic lupus erythematosus, reactive arthritis, Reiter's syndrome, Crohn's disease, ulcerative colitis); * Participants with diseases that affect healing (e.g. diabetes); * Immunocompromised participants; * Participants with aphthous herpetiform ulceration or major aphthous ulceration; * Participants using medication to treat oral ulcerations (systemic or local); * Participants who used analgesics or anti-inflammatory drugs in the 6 hours prior to the beginning of the study; * Participants who used systemic antibiotics in the 2 weeks prior to the beginning of the study; * Participants using medications that can confuse pain assessment (psychotropics, antidepressants and sedative-hypnotics), except when on a stable dose for at least 30 days prior to the screening visit, and the dose cannot be changed during the clinical trial; * Participants with current smoking habits. * Participants who are pregnant, breastfeeding or planning to get pregnant or female participants with the potential to become pregnant who are not using a reliable method of contraception; * Known hypersensitivity to the formula components used during the clinical trial; * Participants with current or medical history of cancer in the last 5 years; * Participants who participated in other research protocol in the last 12 months, unless the investigator judges that there may be a direct benefit to it.