Related Experiment Video
Updated: Mar 11, 2026
05:30
Roughness Impact of Piezoelectric Dental Scaler on Two Distinct Flowable Composite Filling Materials
Published on: January 10, 2025
1.1K
Influence of acceleration setting reaction by halogen light-curing on GIC-dentin interface: Qualitative analysis by
Laysa Yoshioka1, Tamara Kerber Tedesco1,2, Ana Flávia Bissoto Calvo1
1Department of Orthodontics and Pediatric Dentistry, University of São Paulo, São Paulo, SP, Brazil.
Microscopy Research and Technique
|November 19, 2016
Summary
Halogen light-curing reduces voids in high-viscosity glass ionomer cements (GIC). This study found that applying light-curing to GIC significantly decreases the size and number of spherical hollow spaces, improving material quality.
Area of Science:
- Dental Materials Science
- Biomaterials Engineering
- Restorative Dentistry
Background:
- High-viscosity glass ionomer cements (GIC) are widely used in pediatric dentistry.
- Understanding factors that affect GIC setting and interface integrity is crucial for clinical success.
- Spherical hollow spaces within GIC can compromise restoration longevity.
Purpose of the Study:
- To investigate the effect of halogen light-curing on the setting reaction of high-viscosity GIC.
- To assess the influence of light-curing on the material/dentin interface using scanning electron microscopy (SEM).
- To quantify the reduction of spherical hollow spaces in GIC with light-curing.
Main Methods:
- Twelve human primary canines were divided into four groups.
- Two types of GIC (Fuji IX, Maxxion R) were used, with and without halogen light-curing (60 seconds).
- SEM analysis was performed on sectioned specimens to evaluate the material/dentin interface and identify hollow spaces.
Main Results:
- Spherical hollow spaces were observed in all experimental groups.
- Groups treated with halogen light-curing exhibited a noticeable decrease in both the size and quantity of these hollow spaces.
- SEM photomicrographs confirmed the positive impact of light-curing on reducing voids within the GIC.
Conclusions:
- Halogen light-curing application positively influences the setting of high-viscosity GIC.
- Light-curing significantly reduces the size and quantity of spherical hollow spaces in GIC.
- This technique may enhance the quality and durability of GIC restorations.
More Related Videos
Related Concept Videos
01:25Accelerated Curing of Concrete
533
Accelerating concrete curing is achieved by applying heat and additional moisture. This process accelerates the hydration of the cement, resulting in an earlier strength gain in the concrete. Steam curing is a method wherein the concrete products are either transported through a chamber on a conveyor belt or encased in plastic, allowing steam at atmospheric pressure to circulate freely around them. This process begins with a phase of moist curing that typically lasts between 3 to 5 hours, after...
533
02:46E1 Reaction: Kinetics and Mechanism
18.3K
Here, in contrast to the E2 reaction mechanism, we delve into the aspects of the E1 reaction mechanism, which has two steps: rate-limiting loss of the leaving group and abstraction of the beta hydrogen by a weak base. Typically, the experimental proof for the E1 mechanism is via kinetic studies or isotope studies. While the former demonstrates the first-order kinetics—the dependence of the reaction solely on substrate concentration—the latter proves the abstraction of hydrogen only...
18.3K
01:17Accelerators
323
Accelerators in concrete serve as admixtures to speed up the hardening process, enabling the concrete to achieve early strength faster. Although accelerators do not necessarily impact the time it takes concrete to set, they reduce this time in practice. A common accelerator is calcium chloride, which is particularly useful for hastening early strength development in cold weather or for rapid repair jobs that require quick heat generation after mixing.
The effectiveness of calcium chloride can...
The effectiveness of calcium chloride can...
323
01:24ortho–para-Directing Deactivators: Halogens
7.0K
Halogens are ortho–para directors. They are more electronegative than carbon. Therefore, as ring substituents, they can withdraw electrons through the inductive effect and deactivate the aromatic ring towards electrophilic substitution. Halogens also have an electron-donating resonance effect on the ring, which influences the orientation of the incoming electrophile. If an electrophile attacks at the ortho or the para position, the halogen donates electrons and stabilizes the intermediate...
7.0K
01:34Radical Halogenation: Thermodynamics
4.6K
The thermodynamic favorability of a reaction is determined by the change in Gibbs free energy (ΔG). ΔG has two components- enthalpy (ΔH) and entropy (ΔS). The entropy component is negligible for alkane halogenation because the number of reactants and product molecules are equal. In this case, the ΔG is governed only by the enthalpy component. The most crucial factor that determines ΔH is the strength of the bonds. ΔH can be determined by comparing the energy...
4.6K