Evaluation of the chelating effect of chitosan solubilized in different acids: analysis through dentin microhardness and colorimetry

• Grant number: 13/22959-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2014
• End date: May 31, 2015
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Antonio Miranda da Cruz Filho
• Grantee: Paôla Caroline da Silva Mira
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

The present study aims to compare, through the dentin microhardness and Colorimetry, the chelating effect of chitosan 0.2 % solubilized in different acids. Will be used 10 central incisors, which will have their crowns cut and discarded. The remaining root will be included in acrylic resin and the crosswise bloc will be cut in hard tissue cutting machine. The second and third sections of the cervical region will be divided into four quadrants, which will be embedded in acrylic resin specimens yielding 8 per root. The specimens will be treated with 0.2% chitosan solution prepared as follow: GI- 0.2% chitosan solubilized in 1% acetic acid; GII - 0.2 % chitosan solubilized in 3.3% citric acid; GIII - 0.2% chitosan solubilized in 0.00145% hydrochloric acid, and GIV - 0.2% chitosan solubilized in 0.00112% nitric acid. In parallel , there will be a control chelating property of solubilizing acids as groups : GV - 3.3% citric acid; GVI - 0.00145 % hydrochloric acid; GVII - 0.00112% nitric acid; and GVIII - control (distilled water). Each specimen will receive a solution of 50mL for 5 minutes. After washing and drying it will be brought to the microhardness machine,Knoop, with a load of 10g for 15 seconds. Three indentations will be performed in the sense of the root canal towards the cement . The measurements obtained will be subjected to statistical analysis. Immediately after preparation of the solutions of chitosan , the same shall be submitted to the test of Colorimetry in order to verify that the chelating property of solution was kept and quantify the volume needed to chelate all calcium standard solution . The results of both tests , microhardness and colorimetry will be correlated.