Cytotoxicity of two fluoride-releasing adhesive tapes

Sodium fluoride-polyvinyl alcohol (NaF-PVA) tape was developed to deliver fluoride to teeth by adding fluoride to polymer tape. Previous studies have demonstrated that tapes are effective and have antimicrobial properties. This study aimed to evaluate the cytotoxicity of two fluoride-releasing adhesive tapes. We investigated two polyvinyl alcohol (PVA) tapes: (i) a fluoride-PVA (F-PVA) tape, and (ii) a pullulan-incorporated F-PVA (PF-PVA) tape. The cytotoxicity test was conducted on human gingival fibroblasts (HGF) and human periodontal ligament (PDL) cells. Using an adhesive tape containing fluoride, we performed the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on these cells. Genetic analysis of the cells was performed to conduct a stability test on humans. In the MTT assay, PF-PVA had 66% greater cytotoxicity than control by PDL and 69% by HGF. F-PVA showed less cytotoxicity than PF-PVA by 29% in PDL and 33% in HGF. Gene ontology (GO) analysis and gene set enrichment analysis (GSEA) were performed as gene expression analyses. GO analysis indicated that PF-PVA displayed more expression changes of genes related to cytotoxicity than F-PVA. In addition, GSEA found more inflammatory response associations in PF-PVA than in F-PVA. MTT and genetic testing yielded comparable results.