## 7 Activity of Ceragenins in the Presence of Saliva and Dental Plaque
Recent Achievements in the Development of Ceragenin-Based Oral Formulations for the Prevention and Therapy of Oral Diseases  
The use of ceragenins in the creation of formulations to effectively maintain oral hygiene, both as a preventive measure and for treatment purposes, is continuing to be explored. Over the last two years, two studies were published with potential applications. In the first, published by [PERSON] et al. in 2022 [158], the potential of ceragenin CSA-44 to control mature biofilms of _E. faecalis_ and _C. albicans_ and in vitro biofilm prevention onremoved teeth and composite disks was examined. The study was motivated by two practical facts: (i) the necessity of repair or replacement of acrylic fillings after _C. albicans_ infection and (ii) the correlation between biofilm formation on teeth and dental fillings, usually made of composite materials, with the development of caries and periodontal diseases. The authors demonstrated that upon administration of CSA-44, a significant decrease in clusters of biofilm structures was noted, which indicates the protective effects of CSA-44 against mono- and dual-species biofilms. A decrease in stiffness of CSA-44-treated biofilm was also recorded, suggesting it potentially facilitated the removal of the biofilm and possibly improved the penetration of other antimicrobials into the biofilm matrix. When examining the impact of microorganisms on dental composites, no discernible impact on the polymer structure or visible damage in the form of micro-cracks or other mechanical degradation caused by biofilm was observed. Our most recent study also emphasizes the potential use of ceragenins as components of oral mouthwashes to prevent/restrict the spread of oral infections [140]. This is achieved through the antimicrobial effect of ceragenins on planktonic and biofilm forms of _Candidia_ fungi, as well as anaerobic and aerobic oral disease-associated bacteria, such as _B. fragilis, E. faecalis_, and _S. mutans_. The research has shown that ceragenins CSA-13, CSA-44, CSA-131, and CSA-255 exhibit potent antimicrobial and antib biofilm effects against well-recognized representatives of bacterial and fungal pathogens found in the oral cavity. Notably, those effects were observed at a relatively low concentration of ceragenins of approx. 5-10 ug/mL, which are recognized as non-toxic against human gingival fibroblasts and human erythrocytes used as host-derived cells to assess ceragenin toxicity. Importantly, our study is the first to compare the effectiveness of ceragenin-containing solutions with six commercially available mouthwashes containing cetylpyridinium chloride, chlorhexidine digluconate, ocentidine, or essential oils (with or without alcohol). Even though ceragenins exhibited comparable or slightly reduced efficacy relative to commercially available mouthwashes, they were distinguished by their lower toxicity toward host cells. This may potentially result in an improved maintenance of the stability of the host mucosal membrane [140]. These results, although carried out in in vitro settings, strongly suggest that ceragenins could be used in novel approaches for treatment of oral infections, and further research on the development of ceragenin-containing formulations is warranted. Clinical Introduction of Ceragenins--Future Directions for Research on Ceragenin-Containing Oral Formulations  
The extensive array of biological actions of ceragenins suggests several applications for ceragenins (Figure 3). Although a great majority of research regarding the antimicrobial and non-antimicrobial features of ceragenins was performed preclinically, some ceragenin-based solutions have entered a clinical research stage and are commercialized. Currently, the most advanced and clinically acceptable are ceragenin-coated endotracheal tubes designed to prevent the development of ventilator-associated pneumonia (VAP) in critically ill, high-risk patients and to significantly lower overall costs of hospital care [160].