Oral cavity: An open horizon for nanopharmaceuticals

Oral administration is the primary route employed for drug delivery. In addition to the gastrointestinal tract, the oral cavity has been drawing considerable attention owing to its physiological properties and advances in drug carrier development. Notably, nanotechnology has made immense contributions to enhancing drug bioavailability, stability, and efficacy, both in research and clinical settings. The present review comprises lessons from physiological characteristics to fundamental material science knowledge, summarizing the pros and cons of nanotechnology applications in therapeutic drug delivery. The oral cavity presents inherent challenges, including oral cancer, dental caries, oral infection, or oral inflammation, that necessitate local solutions. Simultaneously, the vascular system under the tongue and in the buccal region offers a portal for systemic drug absorption. Among available delivery systems, nanoparticle-based drug delivery, with the oral cavity as the action or absorption site, can be developed as a principal dosage formulation. Although convenience and fast onset might be advantageous, additional studies are warranted for preclinical characterization, especially in animal models, and for determining manufacturing competence, prior to human trials to meet standards in clinical settings.