Evaluation of the transdentinal capability of the intrinsic antibacterial cetylpyridinium chloride/cholesterol sterosomes in vitro and in vivo

Aim Dentinal tubules serve as disease-causing channels for infiltration and penetration of bacteria and their by-products; which are regarded as the major driver of pathogenesis in pulpal inflammation and infection. In this study, we aimed to evaluate the transdentinal potential of nanoscale cetylpyridinium chloride/cholesterol (CPC/Chol) sterosomes, which are a recently developed type of cationic non-phospholipid liposomal nanocarrier; as well as their intrinsic and universal antibacterial activity. Methodology Cetylpyridinium chloride/cholesterol sterosomes were formulated, with a hydrodynamic diameter of 134 +/- 4 nm, a low polydisperse index of 0.161 +/- 0.007, and a positive zeta potential of 41 +/- 3 mV at pH 7.4. Transdentinal diffusion ability of sterosomes was evaluated using human dentine blocks in vitro, and Wistar rat molar teeth in vivo. The intrinsic antibacterial activities of CPC/Chol sterosomes against Enterococcus faecalis, Streptococcus mutans, Fusobacterium nucleatum, and Porphyromonas gingivalis were further examined. Results Cetylpyridinium chloride/cholesterol sterosomes successfully penetrated through the dentinal tubules, and diffused into the pulp, which could be internalized by dental pulp cells with a high efficiency. In addition, they exhibited substantial levels of intrinsic antibacterial activity against these Gram-positive and Gram-negative endodontic bacteria and their biofilms. Conclusions Given its high penetration and diffusion ability through the dentine and pulp, great potential for multi-drug delivery, and distinct intrinsic antibacterial activity; sterosome-based nanocarriers might serve as a promising therapeutic strategy aimed at targeting various specific pathways associated with pulpal diseases. This will help determine and characterize the most appropriate prophylactic and therapeutic targets for early intervention in our future dentistry practice.

Automated summary

The transdentinal potential and antibacterial activity of nanoscale CPC/Chol sterosomes were evaluated in this study. The sterosomes successfully penetrated through dentinal tubules and diffused into the pulp with high efficiency, exhibiting substantial intrinsic antibacterial activity against endodontic bacteria and biofilms. These findings suggest that sterosome-based nanocarriers hold promise as a therapeutic strategy for targeting specific pathways associated with pulpal diseases.