Author(s): Balsam M. Mirdan, Shakir M. Lafta
Abstract. The research was performed to calculate the amount of the loss from the light incident on the tooth structure at the 1.064µm and 0.532 µm wavelengths via reflection and transmission. The d iffused scattering spectra at 400-900 µm were measured, too. The aim was to find a wavelength that possesses a stable behavior with the tooth structure. To find the suitable wavelength that is not influenced by the dryness of the tooth during laser irradiation. Material and method: UV/VIS/NIR spectrometer was implemented to measure the transmission and scattering spectra of.1mm thickness of wet human teeth as a function of time. The change in the light behavior was recorded during the experiment. Results: There was a dramatic drop in the amount of transmitted light as the tooth gets dry with time which may be due the abrupt increase in the variation in the refractive index at the interface between the incident media to the transmitted media. Recommendation: the presence of water at the interface between air and tooth surface influences the light behavior at 1.064µm while for 0.532 µm wavelength the light was not affected.