Related Experiment Video
Updated: Jul 13, 2026

In Vitro Evaluation of The Effects Of Er,Cr:YSGG and Diode Lasers Used on Titanium Cylinder
Published on: June 6, 2025
Analysis of Er:YAG lased dentin using attenuated total reflectance Fourier transform infrared and X-ray diffraction
Ahmed Samir Bakry1, Alireza Sadr, Hidekazu Takahashi
1Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8549, Japan. bakry.ope@tmd.ac.jp
Abstract:
The purpose of this study was to investigate the chemical characteristics of dentin after Er:YAG laser irradiation using various output energies with or without water irrigation. Analysis was carried out by means of attenuated total reflectance Fourier transform infrared spectroscopy (FT-IR/ATR) and X-ray diffraction (XRD). Furthermore, the relative infrared peak intensities of dentin specimens were compared statistically. Results showed that Er:YAG laser with an output energy of 100 mJ/pulse with water irrigation did not cause any detectable change in dentin. However, a higher energy output or the absence of water irrigation affected the organic portion of dentin. With XRD, no obvious phase changes were observed between the XRD pattern of the control (non-irradiated) dentin powder and those after Er:YAG irradiation - regardless of Er:YAG laser output energy or dehydration condition. It was suggested that the intrinsic water content of dentin - together with extrinsic water irrigation - were important factors to achieving the desired outcome of dentin ablation by Er:YAG laser.
Related Concept Videos
Attenuated Total Reflectance (ATR) Infrared Spectroscopy: Overview
The ATR process begins by directing a beam...
X-ray Crystallography
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
X-ray Diffraction of Biological Samples
According to Bragg's law, when X-rays strike the sample positioned on a stage, the rays are scattered by the electron clouds around the sample atoms. The X-ray diffraction or scattering is caused by constructive interference of the X-ray waves that reflect off the internal crystal...
Determination of Crystal Structures