Mouth Ulcers Treatment Market By Drug Class (Analgesics And Corticosteroids , Antihistamine, Antimicrobial, Anesthetic); By Formulation Type (Sprays, Mouthwash, Gels, Lozenges); By Indication (Aphthous Stomatitis, Oral Lichen Planus, Others); By Region (North America, Europe, Asia Pacific, Middle East & Africa (Mea), South America) : Global Opportunity Analysis And Industry Forecast 2021-2027