Chemical composition profile of CO2 laser irradiated enamel

• Grant number: 17/03163-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2017
• End date: April 30, 2018
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Luciano Bachmann
• Grantee: Carla Regina Albino
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

The project will employ FTIR (Fourier transform infrared spectroscopy) and a progressive enamel wear to monitor the chemical composition at subsurface of the enamel after irradiation with CO2 laser (10.6 ¼m) using 3 irradiation parameters: 3 J/cm2 /5¼s; 1,25 J/mm2 /20¼s; 1,63 J/mm2 /33¼s. The analysis will evaluate the extension of laser action on enamel, such as carbonate loss, water loss or other changes in the mineral matrix as changes in phosphate radical. To aces the chemical composition profile we employ the FTIR spectroscopy, a microdurometer to produce marks that are able to measure the progressive wear, a polish machine to carry out the progressive tissue removal that will produce the controlled wear with steps of 0.5-1.0m, and optical microscope to measure the marks and the perfilometer to evaluate the enamel surface. As an example, we can take the carbonate radical; it is expected to observe its elimination on the irradiated surface and after progressive abrasion the carbonate will be restored up initial values. Similar profiles can be observed for water and other changes in the phosphate radical. (AU)