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VOLUME 13 , ISSUE 6 ( November-December, 2022 ) > List of Articles


Comparison of Four Different Light-curing Units and Evaluation of the Depth of Cure and Microhardness of Nanohybrid Composite Resin

Megha Gugnani, Mamta Singla, Mandeep S Grewal, Anshul Arora, Gaurav Setya, Ayush Jain

Keywords : Depth of cure, Hardness ratio, Light-emitting diode, Nanohybrid composite, Vickers hardness

Citation Information : Gugnani M, Singla M, Grewal MS, Arora A, Setya G, Jain A. Comparison of Four Different Light-curing Units and Evaluation of the Depth of Cure and Microhardness of Nanohybrid Composite Resin. World J Dent 2022; 13 (6):611-616.

DOI: 10.5005/jp-journals-10015-2114

License: CC BY-NC 4.0

Published Online: 26-08-2022

Copyright Statement:  Copyright © 2022; The Author(s).


Aim: The current in vitro study compared four different light-curing units and evaluated the depth of cure and microhardness of nanohybrid composite resin. Materials and methods: Ninety-six composite specimens were obtained using polyurethane molds with 5 mm diameter and 2, 4, and 6 mm depth. Each specimen was light-cured using four different light-curing units (Bluephase N, iLED, SmartLite Focus, and Elipar DeepCure-L) for 20 seconds. The Vickers microhardness (VK) of the surface was determined by a microhardness indenter with a load of 200 gm applied for 15 seconds. The hardness ratio = VK of the bottom surface/VK of the top surface was calculated and compared. Depth of cure using a scraping method described in the International Organization for Standardization (ISO) standard for resin-based composites was performed, and mean was calculated and compared. Results: Data were analyzed using analysis of variance (ANOVA) test. Significant differences were found in hardness ratio and depth of cure (DOC) of samples cured by abovementioned light sources. Conclusion: Bluephase N reaches the minimum value indicated in literature (0.8) and depth of cure of 1.5 as compared to other light-curing units. Clinical significance: Clinicians need to follow the manufacturer's instructions for each light and to be cured accordingly to obtain a properly cured composite resin.

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