**14. Restoration of tissue damage from PD: potential of current Nano RES formulations**

Nano-RES formulations intended specifically for the treatment of PD, are only beginning to emerge. For example, Berta et al., reported a nano-formulated REScyclodextrin mouthwash that was found to reduce plaque and bleeding gums in children [132]. Nonetheless, there are several nano RES formulations, intended to treat other conditions, which could, in theory, be studied as potential formulations for PD, with little divergence from the original formula.

For example, in a 2021 study, Li and colleagues produced nano-hydroxyapatite-RES-chitosan (CS) microspheres for bone generation, which could potentially be used to restore bone loss due to PD [133].

Also, electrospun 3-D nano-scaffolds loaded with RES, consisting of a biodegradable polymer (PLA)-biopolymer-gelatin (GEL) nano-scaffold was found to repair cartilage defects in the rat model [134].

Notably, monodispersed, spherical chitosan-zinc oxide-RES (CS-ZnO-RES) nanoparticles (NP) (38 nm) engineered by Du et al., were reported to attenuate gestational DM (GDM) [135].

Moreover, the successful application of nano-RES as a potential treatment for AD has been reported by Sun et al., who designed a RES-loaded mesoporous selenium-Fcβ-cyclodextrin-Borneol nanoparticle that crossed a blood-brain barrier model [136].
