Degree of conversion of different composite resins photo-activated with light-emitting diode and argon ion laser

Clinical Relevance Irradiance may decrease as the light-emitting diode (LED) is discharged. Therefore, the LED must be charged carefully to prevent the possibility of influencing the chemical, mechanical, and physical properties of composite resin. SUMMARY The aim of this study was to evaluate the influence of different light-emitting diode (LED) curing units and battery levels on the chemical, mechanical, and physical properties of composite resins. The irradiance for each cycle from full to completely discharged battery level was evaluated, for five different new cordless LED units: Optilight Color (Gnatus), Bluephase (Ivoclar), Valo (Ultradent), Radii Plus (SDI), and Radii Xpert (SDI). After the irradiance evaluation, composite resin specimens were prepared and light cured, while varying the battery level for each LED unit: high level (HL, 100%), medium level (ML, 50%), and low level (LL, 10%). The degree of conversion, diametral tensile strength, sorption, and solubility were also evaluated. Data were checked for homoscedasticity and submitted to two-way and three-way analysis of variance, depending on the test performed, followed by the Tukey test with a significance level of 95%. A negative correlation was found between irradiance and cycles of light curing, which was checked by the Pearson correlation test. Valo and Radii Xpert were not influenced by the battery level in any test performed. However, different battery levels for some LED units can influence the degree of conversion, diametral tensile strength, sorption, and solubility of composite resins.

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Effect of different light sources on degree of conversion, hardness and plasticization of a composite

Journal of Research in Dentistry ◽

10.19177/jrd.v1e22013134-139 ◽

2013 ◽

Vol 1 (2) ◽

pp. 134

Author(s):

Bruno de Castro Ferreira Barreto ◽

Anderson Catelan ◽

Ricardo Coelho Okida ◽

Gisele Fernanda Gonçalves ◽

Gisele Rodrigues da Silva ◽

...

Keyword(s):

Clinical Performance ◽

Light Emitting Diode ◽

Knoop Hardness ◽

Composite Resins ◽

Degree Of Conversion ◽

Light Sources ◽

Light Emitting ◽

Quartz Tungsten Halogen ◽

Light Curing ◽

Ft Ir

Clinical performance of composite resins depends largely on their mechanical properties, and those are influenced by several factors, such as the light-curing mode. The purpose of this study was to evaluate the influence of different light sources on degree of conversion (DC), Knoop hardness (KHN) and plasticization (P) of a composite resin. Disc-shaped specimens (5 x 2 mm) of Esthet-X (Dentsply) methacrylate-based microhybrid composite were light-cured using quartz-tungsten-halogen (QTH) Optilight Plus (Gnatus) or light-emitting diode (LED) Ultraled (Dabi Atlante) curing units at 400 and 340 mW/cm2 of irradiance, respectively. After 24 h, absorption spectra of composite were obtained using Nexus 670 (Nicolet) FT-IR spectrometer in order to calculate the DC. The KHN was measured in the HMV-2000 (Shimadzu) microhardness tester under 50 g loads for 15 s, and P was evaluated by percentage reduction of hardness after 24 h of alcohol storage. Data were subjected to t-Student test (alpha = 0.05). QTH device showed lower P and higher KHN than LED (p < 0.05), and no difference between the light-curing units was found for DC (p > 0.05). The halogen-curing unit with higher irradiance promoted higher KHN and lower softening in alcohol than LED.

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Basic study on visible light activated dental composite resins - Polymerization and curing properties in argon ion laser irradiation.

The Review of Laser Engineering ◽

10.2184/lsj.17.9_642 ◽

1989 ◽

Vol 17 (9) ◽

pp. 642-651 ◽

Cited By ~ 2

Author(s):

Kaoru SUZUKI ◽

Shigeyuki MASUTANI ◽

Tetsuya TANIYAMA ◽

Junji NAKATA ◽

Takaya MASUTANI

Keyword(s):

Visible Light ◽

Laser Irradiation ◽

Composite Resins ◽

Dental Composite ◽

Basic Study ◽

Argon Ion Laser ◽

Dental Composite Resins ◽

Ion Laser ◽

Argon Ion

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Laser Induced Etching for Generation of Si Nanocrystals and Spectroscopic Investigation of Morphology

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.23.43 ◽

2005 ◽

Vol 23 ◽

pp. 43-46

Author(s):

H.S. Mavi ◽

S. Rath ◽

Arun Shukla

Keyword(s):

Quantum Confinement ◽

Silicon Nanocrystals ◽

Laser Wavelength ◽

Interconnected Network ◽

Substrate Type ◽

Argon Ion Laser ◽

Si Nanocrystals ◽

Ion Laser ◽

Laser Induced Etching ◽

Argon Ion

Laser-induced etching of silicon is used to generate silicon nanocrystals. The pore structure depends on the substrate type and etching laser wavelength. Porous silicon (PS) samples prepared by Nd:YAG laser (1.16 eV) etching of n-type substrate showed a fairly uniform and highly interconnected network of nearly circular pores separated by thin columnar boundaries, while no circular pits were produced by argon- ion laser (2.41 eV) etching under similar conditions. The size and size distribution of the nanocrystals are investigated by Raman and photoluminescence spectroscopies and analyzed within the framework of quantum confinement models.

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Electron temperatures in a segmented-metal argon-ion laser

Journal of Physics D Applied Physics ◽

10.1088/0022-3727/5/10/309 ◽

1972 ◽

Vol 5 (10) ◽

pp. 1807-1814 ◽

Cited By ~ 6

Author(s):

A Maitland ◽

J C L Cornish

Keyword(s):

Argon Ion Laser ◽

Ion Laser ◽

Argon Ion

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ChemInform Abstract: High-Intensity, Argon Ion Laser-Jet Photochemistry. Reactions Between Transient Species: The Addition of Diphenylcarbene to the Photoenol of 2-Methylbenzophenone.

ChemInform ◽

10.1002/chin.199318113 ◽

2010 ◽

Vol 24 (18) ◽

pp. no-no

Author(s):

R. M. WILSON ◽

K. A. SCHNAPP ◽

W. S. PATTERSON

Keyword(s):

High Intensity ◽

Transient Species ◽

Argon Ion Laser ◽

Ion Laser ◽

Argon Ion

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Spectroscopic Properties of Photoproduct of Hematoporphyrin Derivative Oligomer by Photoradiation of Argon-ion Laser

Nippon Laser Igakkaishi ◽

10.2530/jslsm1980.8.4_3 ◽

1988 ◽

Vol 8 (4) ◽

pp. 3-9

Author(s):

Norio MIYOSHI ◽

Takahiro SEKI ◽

Shuichi KINOSHITA ◽

Takashi KUSHIDA ◽

Tsuyoshi NISHIZAKA ◽

...

Keyword(s):

Spectroscopic Properties ◽

Hematoporphyrin Derivative ◽

Argon Ion Laser ◽

Ion Laser ◽

Argon Ion

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Surface Hardness of Nanohybrid and Microhybrid Resin Composites Cured by Light Emitting Diode and Quartz Tungsten Halogen Light Curing Systems: An Invitro Study

JOURNAL FOR CLINICAL AND DIAGNOSTIC RESEARCH ◽

10.7860/jcdr/2020/43875.13834 ◽

2020 ◽

Author(s):

Anuradha Vitthal Wankhade ◽

Sharad Basavraj Kamat ◽

Santosh Irappa Hugar ◽

Girish Shankar Nanjannawar ◽

Sumit Balasaheb Vhate

Keyword(s):

Light Emitting Diode ◽

Surface Hardness ◽

Composite Resins ◽

Resin Composites ◽

Light Emitting ◽

Quartz Tungsten Halogen ◽

Halogen Light ◽

Intergroup Comparison ◽

Light Curing ◽

Curing Systems

Introduction: New generation composite resin materials have revolutionized the art of aesthetic dentistry. The clinical success is dependent on effective polymerisation and surface hardness which in turn are dependent on the performance of Light Curing Units (LCU). This study utilises surface hardness as a measure of degree of polymerisation of composite resins achieved by LCUs. Aim: To evaluate the difference in surface hardness of nanohybrid and microhybrid resin composites cured by light curing systems, Light Emitting Diode (LED) and Quartz Tungsten Halogen (QTH). Materials and Methods: In this invitro experimental study, two types of hybrid composites (Nanohybrid and Microhybrid) were tested for surface hardness by using two different light curing systems (LED and QTH). All the Nanohybrid and Microhybrid specimens were cured using LED and QTH LCUs, thus giving four combinations. A total of 60 specimens (6 mm diameter and 2 mm depth) were prepared using Teflon mould with 15 samples for each combination. Surface hardness was measured on upper and lower surface after 24 hours and hardness ratio was calculated. Data was analysed using independent t-test for intergroup comparison. Level of significance was kept at 5%. Results: Surface hardness of resin composites cured by LED LCU was greater than those cured by QTH LCU. Additionally, the hardness value was greater for the upper surface. Nanohybrids showed better surface hardness than Microhybrids for both the LCUs. Conclusion: Nanohybrid composite resins and LED system were found to be more effective in terms of surface hardness as compared to their counterparts.

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