Investigation of gastric acid effect on chitosan modified glass ionomer cement

The aim of this study is to investigate surface microhardness and roughness properties of a modified glass ionomer cement composed by adding different ratios of Chitosan, with antibacterial properties, exposed to saliva and acid erosive gastric acid cycle environments. Chitosan with low molecular weight was added in conventional glass ionomer (GC Fuji IX GP EXTRA, GC Corporation, Tokyo, Japan) liquid by volume of 5% and 10% , after dissolution in 1% acetic acid, chitosan modified glass ionomer was used for experimental group whereas tradiotanal glass ionomer was formed the control. All the groups were derided to two subgroups an done subgroups was subjected to gastric acid erosive cycle 6 times a day for 60 seconds and at the and of the each cycle the examples were immersed in prepared artificial saliva the other subgroup was immersed in artificial saliva for 10 days. Microhardness measurements of all the samples were done by Buehler MMT-3 digital microhardness tester (Lake Bluff, IL, USA). The surface roughness measurements were made with the optical profilometer device (Phaze View / Zee Scope, France) and the atomic force microscope device Veeco Multimode 8 (Santa Barbara, CA, USA). Qualitative surface topographic evaluations were performed with the help of the scanning electron microscope device Quanta FEG 650 (FEI Company, Hillsboro, Oregon, USA). Statistical analyzes of the results were performed with Kruscall Wallis and Wilcoxon Signed Ranks Tests. As a result of the addition of chitosan, the microhardness and surface roughness properties of glass ionomer cement have been affected positively. Artificial saliva increased the microhardness values of the control and experimental groups in our study. However, in terms of surface roughness, chitosan modified glass ionomer cement groups were adversely affected. Gastric acid erosive cycle application negatively affected the microhardness and surface roughness properties of the sample groups. In our in vitro study, chitosan modified glass ionomer cement samples have shown clinically acceptable surface roughness values. The addition of chitosan positively affected the microhardness values. Further, In vitro and in vivo studies are needed for chitosan modified glass ionomer cement.