The Effects of Light Intensity and Light-curing Time on the Degree of Polymerization of Dental Composite Resins

In this study, the wear characteristics of five different dental composite resins cured by conventional halogen light and LED light sources were investigated. Five different dental composite resins of Surefil, Z100, Dyract AP, Fuji II LC and Compoglass were worn against a zirconia ceramic ball using a pin-on-disk type wear tester with 15 N contact force in a reciprocal sliding motion of sliding distance of 10 mm/cycle at 1Hz under the room temperature dry condition. The wear variations of dental composite resins were linearly increased as the number of cycles increased. It was observed that the wear resistances of these specimens were in the order of Dyract AP > Surefil > Compoglass > Z100 > Fuji ı LC. On the morphological observations by SEM, the large crack formation on the sliding track of Fuji ıLC specimen was the greatest among all resin composites. Dyract AP showed less wear with few surface damage. There is no significant difference in wear performance between conventional halogen light curing and light emitting diodes curing sources. It indicates that a light emitting diodes (LED) source can replace a halogen light source as curing unit for composite resin restorations.

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Evaluation of Light Curing Distance and Mylar Strips Color on Surface Hardness of Two Different Dental Composite Resins

The Open Dentistry Journal ◽

10.2174/1874210601408010144 ◽

2014 ◽

Vol 8 (1) ◽

pp. 144-147 ◽

Cited By ~ 3

Author(s):

Seyed Mostafa Mousavinasab ◽

Mehrdad Barekatain ◽

Elahe Sadeghi ◽

Farzaneh Nourbakhshian ◽

Amin Davoudi

Keyword(s):

Dental Materials ◽

Surface Hardness ◽

Hardness Test ◽

Composite Resins ◽

Dental Composite ◽

Test Machine ◽

Dental Composite Resins ◽

Light Curing ◽

Spss Software ◽

Temperature Surface

Introduction:Hardness is one of the basic properties of dental materials, specially composite resins which is relevant to their polymerization. The aim of this study was to evaluate the effect of light curing distance and the color of clear Mylar strips on surface hardness of Silorane-based (SCR) and Methacrylate-based composite resins (MCR).Materials and methods:40 samples of MCRs (Filtek Z250) and SCRs (Filtek P90) were prepared in size of 5 mm×2 mm (80 samples in total). The samples divided into 8 groups (10 samples in each one) based on the color of clear Mylar strips (white or blue) and distance from light curing source (0 mm or 2 mm). All the samples cured for 40 second and stored in incubator for 24 hours in 37°C temperature. Surface hardness test was done by Vickers test machine and the collected data were analyzed by one-way ANOVA and paired T-test by using SPSS software version 13 at significant level of 0.05.Results:MCRs cured with blue Mylar strips from 0 mm distance had the highest (114.5 kg/mm2) and SCRs cured with white Mylar strips from 2 mm distance had the lowest (42.2 kg/mm2) mean of surface hardness. Also, the results of comparison among SCRs and MCRs showed significant differences among all groups (all P values <0.01).Conclusion:The hardness decreased as the distance increased and the blue Mylar strips provided higher hardness than clear ones. Also, Filtek Z250 showed higher hardness compared to Filtek P90.

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Effect of the Time of Salivary Contamination during Light Curing on Degree of Conversion and Microhardness of a Restorative Composite Resin

Biomimetics ◽

10.3390/biomimetics3030023 ◽

2018 ◽

Vol 3 (3) ◽

pp. 23 ◽

Cited By ~ 1

Author(s):

Rasoul Sahebalam ◽

Alireza Boruziniat ◽

Fahimeh Mohammadzadeh ◽

Abdolrasoul Rangrazi

Keyword(s):

Composite Resin ◽

Clinical Problem ◽

Human Saliva ◽

Point Of View ◽

Composite Resins ◽

Degree Of Conversion ◽

Dental Composite ◽

Dental Composite Resins ◽

Light Curing ◽

Saliva Contamination

Saliva contamination is a major clinical problem in restorative procedures. The purpose of this study was to evaluate the effect of the time of salivary contamination during light curing on the degree of conversion and the microhardness of a restorative composite resin. Eight groups of 10 samples for measuring the microhardness and eight groups of 5 samples for evaluating the degree of conversion were prepared. The samples of each group were contaminated with human saliva at a certain time. The first group (T0) was contaminated before light curing. The specimens in groups T2–T30 were contaminated at 2, 5, 10, 15, 20 and 30 s after the start of light curing, respectively. The samples of group T40 were contaminated after light curing. The degree of conversion and the microhardness of the specimens were measured by Fourier transform infrared (FTIR) spectroscopy and Vickers hardness testing techniques, respectively. The results of this study revealed that there were no significant differences between the groups in terms of the degree of conversion of the composite resin. Consistent with the findings for the degree of conversion, significant differences in the microhardness between the groups were not found. In conclusion, from a clinical point of view, the results of our study showed that the time of salivary contamination (before, during or after light curing of composite resin) has no significant effect on the polymerization (degree of conversion) and one of the important mechanical properties of dental composite resins (microhardness).

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Interactive effects of resin composition and ambient temperature of light curing on the percentage conversion, molar heat of cure and hardness of dental composite resins

Journal of Materials Science Materials in Medicine ◽

10.1007/bf00702940 ◽

1992 ◽

Vol 3 (1) ◽

pp. 19-27 ◽

Cited By ~ 25

Author(s):

J. Vaidyanathan ◽

T. K. Vaidyanathan

Keyword(s):

Ambient Temperature ◽

Composite Resins ◽

Dental Composite ◽

Interactive Effects ◽

Dental Composite Resins ◽

Light Curing ◽

Percentage Conversion

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Effect of light-curing units on microleakage under dental composite resins

Laser Physics ◽

10.1134/s1054660x09170174 ◽

2009 ◽

Vol 19 (9) ◽

pp. 1909-1911 ◽

Cited By ~ 4

Author(s):

R. S. Queiroz ◽

M. C. Bandéca ◽

L. R. Calixto ◽

E. G. Saade ◽

M. R. Nadalin ◽

...

Keyword(s):

Composite Resins ◽

Dental Composite ◽

Dental Composite Resins ◽

Light Curing ◽

Effect Of Light

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Interactions Between Dental Composite Resins and Saliva A comparative biochemical in vitro study

Materiale Plastice ◽

10.37358/mp.19.3.5223 ◽

2019 ◽

Vol 56 (3) ◽

pp. 529-533

Author(s):

Mihaela Pantea ◽

Diana Andreea Ighigeanu ◽

Alexandra Totan ◽

Maria Greabu ◽

Daniela Miricescu ◽

...

Keyword(s):

Oxidative Stress ◽

In Vitro Study ◽

Composite Resins ◽

Vitro Study ◽

Dental Composite ◽

Gamma Glutamyl Transferase ◽

Specific Protocol ◽

Dental Composite Resins ◽

Glutamyl Transferase

This in vitro study analyses the biochemical interaction between saliva and three types of dental composite resins (a direct resin, an indirect resin and a dual-cure resin used for cementation of indirect dental restorations). The resin samples were obtained following a specific protocol and in line with the producers� recommendations; the resin samples were incubated with saliva samples collected from 19 healthy volunteers. The obtained results showed that the tested composite resins did not produce significant changes in oxidative stress parameters that were analysed (albumin, uric acid, GGT / gamma glutamyl transferase, OXSR-1 / oxidative stress responsive kinase 1) and do not influence the inflammatory salivary status reflected by the levels of IL-6 - an inflammatory marker.

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