Related Experiment Video
Updated: Jun 21, 2026

In situ Photo-rheology Monitors Viscoelastic Changes in Photo-responsive Polymer Networks
Published on: June 20, 2025
Relative efficiency of radiation sources for photopolymerization
Rie Nomoto1, John F McCabe, Keiko Nitta
1Department of Dental Engineering, Tsurumi University School of Dental Medicine, 2-1-3 Tsurumi, Tsurumi-ku, Yokohama 230-8501, Japan. nomoto-r@tsurumi-u.ac.jp
Abstract:
The aim of this study was to evaluate the characteristics of new-generation light-emitting diode (LED) units in comparison with the conventional tungsten-halogen, plasma arc, and first-generation LED units reported in our previous study. The irradiance of light from new-generation LED units, the temperature rise of the bovine enamel surface, and the depth of cure of composites exposed to each unit were investigated. The irradiances in the range 400-515 nm emitted from the new-generation LED units were greater than those from the first-generation LED units. The temperature increase was 15-25 degrees C for new-generation LED units compared with a typical value of 5 degrees C for the first-generation LED units at 10 s of irradiation. The relationship between the depth of cure and the logarithm of total exposure energy suggested that LED units can cure light-cured composite resins more efficiently than tungsten-halogen or plasma arc units.

