Related Experiment Video
Updated: Aug 29, 2026
In Vitro Evaluation of The Effects Of Er,Cr:YSGG and Diode Lasers Used on Titanium Cylinder
Published on: June 6, 2025
Effect of Er:YAG laser and organic matrix on porosity changes in human enamel
Deng Ying1, G K Chuah, Chin-Ying S Hsu
1Department of Preventive Dentistry, Faculty of Dentistry, National University of Singapore, 5 Lower Kent Ridge Road, 119074 Singapore, Republic of Singapore.
Objectives:
Cariostatic effects of lasers have been well documented in the past few decades; however, the mechanisms remain unclear. Our previous study revealed the statistically significant effect of organic matrix (OM) in the laser-induced caries prevention. The aim of the present study is to further investigate the role of organic matters in the laser-induced porosity changes.
Methods:
Enamel powder from five sound molars was randomly divided into two samples. One sample was treated with approximately 10% NaClO solution to remove OM and the other was left untreated. Both groups were then subjected to irradiation by an Er:YAG laser. The samples were characterized by thermogravimetric analysis (TGA) and N(2) physico-adsorption.
Results:
TGA results confirmed that the NaClO treatment had at least partially removed the OM in enamel powder. The surface area and pore volume of normal enamel powder decreased significantly after laser treatment. In contrast, in the NaClO-treated enamel powder, laser treatment did not significantly decrease the surface area and the pore volume remained almost unchanged. The substantial difference between the normal enamel powder and the NaClO-treated enamel powder after laser treatment confirmed the laser-induced blocking of OM in the micro-diffusion pathway in enamel.
Conclusion:
The findings in this study seemed to substantiate the "organic blocking theory" as one of the mechanisms in the laser-induced caries prevention.
