Cytotoxic Potential of Vasoconstrictor Experimental Gingival Retraction Agents - in Vitro Study on Primary Human Gingival Fibroblasts (gingival margin retraction agents / cytotoxicity / human gingival fibroblasts)

The aim of this in vitro study was to evaluate the cytotoxic effects of the vasoconstrictor experimental gingival retraction agents (VEGRAs) in a dynamic setting. The strong cytotoxic effects of the astringent-based conventional gingival retraction agents (ACGRAs) on human gingival fibroblasts (HGFs) in vitro was our motivation to evaluate the biocompatibility of the vasoconstrictor-based experimental gingival retraction agents (VEGRAs) for the selected minimally invasive chemical agent. These agents were used to create three self-made retraction gels. Human gingival fibroblasts (HGFs) were treated with two groups of retraction agents: 1) three αand β-adrenergic agents (VEGRA-αβ-s) based on 0.1%, 0.01% and 0.05% HCl-epinephrine, and 2) seven α-adrenergic agents (VEGRA-α-s), including two commercially available 0.05% HCl-tetra hydrozoline solutions, one 0.05% HCl-oxymetazoline solution, 10% HCl-phenylephrine solution, and three new self-made experimental 0.05% HCl-tetrahydroReceived February 16, 2011. Accepted September 22, 2011. corresponding author: Danuta Nowakowska, Department of Dental materials, wroclaw medical university, ul. krakowska 26, 50-425 Wroclaw, Poland. Phone: (+48) 71 7840291; Fax: (+48) 71 7840292; e-mail: [email protected] Abbreviations: AST – aspartate amino-transferase, ACGRAs – astringent-based conventional gingival retraction agents, DMEM – Dulbecco’s Modified Eagle’s Medium, FBS – foetal bovine serum, GRAs – gingival retraction agents, GRFs – gingival retraction fluids, GRGs – gingival retraction gels, GRPs – gingival retraction pastes, HGFs – human gingival fibroblasts, MTT – 3-(4,5-dimethyl-2-thiazollyl)-2,5-diphenyl-2H tetrazolium bromide, PBS – phosphate-buffered saline, VEGRA-α-s – α-ad re nergic vasoconstrictor-based experimental gingival retraction agents, VEGRA-αβ-s – α and β-adrenergic vasoconstrictor-based experimental gingival retraction agents, VEGRAs – vasoconstrictorbased experimental gingival retraction agents. zoline-based gels. The methyl thiazolyl tetrazolium (MTT) colorimetric assay was performed to determine the oxidoreductive mitochondrial function after 3, 5, 10 min and 24 h of incubation. The cytotoxic effect, measured by cell viability lower than the 50% threshold, was not observed at any time period, even 24 h after application of 0.05% HCl-tetrahydrozolinebased self-manufactured retraction gels. High cell viability values of human gingival fibroblasts after the treatment with the three self-made 0.05% HCl-tetrahydrozoline-based gels may serve as a basis for further studies aimed at selecting the best retraction agents biocompatible with gingival margin tissues.