Fluoride-treated Roots and Viability and Attachment of Human Gingival Fibroblasts

Abstract

Topical fluoride treatment is used to help prevent root caries. It may also be useful in periodontal therapy because of its antimicrobial property. In addition, for therapeutic new attachment to occur, the fibroblasts approximating the treated root surface should remain viable, and should also be able to attach and grow onto the treated root surface. These conditions, at least, are required for fluoride not to interfere with new attachment. This study was designed to determine whether treatment of roots with fluoride adversely affects human gingival fibroblasts in culture; and what effect fluoride treatment has on attachment and growth of cells to the root surface.

Cells originally obtained from human gingiva were allowed to grow to confluency in multi-well tissue culture petri dishes, and were then incubated for 24 hr in the presence of root sections as follows: (1) no treatment; (2) root-planed only; (3) 2% NaF only; (4) root-planed + 2% NaF; (5) root-planed + citric acid, pH 1 + 2% NaF. In addition, cells were plated onto roots similarly treated and were subsequently allowed to incubate for 72 hr.

Viability of cells was determined by exclusion of vital dye and ⁵¹Cr retention. Attachment and growth of cells were determined by histology and scanning electron microscopy. Results indicated that, after 24 hours' exposure, there was little or no difference in cell viability between different treatment groups and control cultures. Also, all roots which had been planed accommodated cell attachment, regardless of additional treatment rendered. We conclude that treatment of roots with NaF or citric acid, or both, did not adversely affect the viability of cells, and also that attachment of cells to the roots could occur as long as they were previously planed.