Ceramics-Silikáty 56 (4) 323-330 (2012)

LASER-INDUCED BIOACTIVITY IN DENTAL PORCELAIN MODIFIED BY BIOACTIVE GLASS

A. Beketova, M. Manda, D. Charoulis, D. Christofilos, L. Papadopoulou, O. M. Goudouri, E. Polychroniadis, K. M. Paraskevopoulos, P. Koidis

The aim of this study was to investigate the impact of laser-liquid-solid interaction method in the bioactivity of dental porcelain modified by bioactive glass. Forty sol-gel derived specimens were immersed in Dulbecco's Modified Eagle's Medium, 31 and 9 specimens of which were treated with Er:YAG and Nd:YAG laser respectively. Untreated specimens served as controls. Incubation of specimens followed. Bioactivity was evaluated, using Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM)/Energy Dispersive Spectroscopy (EDS) and Transmission Electron Microscopy (TEM). FTIR detected peaks associated with hydroxyapatite on 1 Nd:YAG- and 4 Er:YAG-treated specimens. SEM analysis revealed that Er:YAG-treated specimens were covered by granular hydroxyapatite layer, while Nd:YAG treated specimen presented growth of flake-like hydroxyapatite. TEM confirmed the results. The untreated controls presented delayed bioactivity. In conclusion, Nd:YAG and Er:YAG laser treatment of the material, under certain fluencies, accelerates hydroxyapatite formation. Nd:YAG laser treatment of specific parameters causes the precipitation of flake-like hydroxyapatite in nano-scale.

Keywords: Laser-liquid-solid interaction, Bioactive glass, Ceramics, Nano-hydroxyapatite, Bioactivity