Adhesion of human gingival fibroblasts/Streptococcus mitis co-culture on the nanocomposite system Chitlac-nAg.

Amelia Cataldi,Eleonora Marsich,Simone Guarnieri,Maria Addolorata Mariggiò,Silvia Sancilio,Mara Di Giulio,Marialucia Gallorini,Luigina Cellini,Roberta Di Pietro,Tonino Traini

doi:10.1007/s10856-016-5701-x

Abstract

Composite materials are increasingly used as dental restoration. In the field of biomaterials, infections remain the main reason of dental devices failure. Silver, in the form of nanoparticles (AgNPs), ions and salt, well known for its antimicrobial properties, is used in several medical applications in order to avoid bacterial infection. To reduce both bacterial adhesion to dental devices and cytotoxicity against eukaryotic cells, we coated BisGMA/TEGDMA methacrylic thermosets with a new material, Chitlac-nAg, formed by stabilized AgNPs with a polyelectrolyte solution containing Chitlac. Here we analyzed the proliferative and adhesive ability of human gingival fibroblasts (HGFs) on BisGMA/TEGDMA thermosets uncoated and coated with AgNPs in a coculture model system with Streptococcus mitis. After 48 h, HGFs well adhered onto both surfaces, while S. mitis cytotoxic response was higher in the presence of AgNPs coated thermosets. After 24 h thermosets coated with Chitlac as well as those coated with Chitlac-nAg exerted a minimal cytotoxic effect on HGFs, while after 48 h LDH release raised up to 20 %. Moreover the presence of S. mitis reduced this release mainly when HGFs adhered to Chitlac-nAg coated thermosets. The reduced secretion of collagen type I was significant in the presence of both surfaces with the co-culture system even more when saliva is added. Integrin β1 localized closely to cell membranes onto Chitlac-nAg thermosets and PKCα translocated into nuclei. These data confirm that Chitlac-nAg have a promising utilization in the field of restorative dentistry exerting their antimicrobial activity due to AgNPs without cytotoxicity for eukaryotic cells.

Highlights

Composite materials are increasingly used in restorative dentistry, but in the broad field of biomaterials, infections remain the main reason of dental devices failure [1]
In order to assess the ability of human gingival fibroblasts (HGFs), S. mitis and the co-culture to adhere onto Bisphenol A glycidylmethacrylate (BisGMA)/ triethylenglicol dimethacrylate (TEGDMA) thermosets, Scanning electron microscopy (SEM) observations and quantifications were run out
As regard S. mitis, the percentage of cells growing onto Chitlac thermosets is significantly higher (96 % of the total surface analysed) with respect to those growing on Chitlac-nAg (6 %)

Summary

Introduction

Composite materials are increasingly used in restorative dentistry, but in the broad field of biomaterials, infections remain the main reason of dental devices failure [1]. The surface of the oral cavity is exposed to a broad variety of microorganisms capable of forming biofilms [2], on oral mucosa and teeth surfaces, and on the components used for dental restoration [3, 4]. It is well known that resin-based composites are susceptible to microbial colonization and to biofilm formation in the oral cavity. In order to avoid the proliferation and the bacterial adhesion on material surface, materials with antimicrobial properties have been set up [6, 7]. In the form of nanoparticles, ions and salt, well known for its antimicrobial properties, is used in several medical and general applications in order to avoid bacterial infection [8, 9]. Silver ions and nanoparticles are capable to destroy the bacterial cell wall by means of the reaction with electron

Objectives

Methods

Results

Conclusion