scholarly journals Water sorption of resin-modified glass-ionomer cements photoactivated with LED

2006 ◽  
Vol 20 (4) ◽  
pp. 342-346 ◽  
Author(s):  
Daniela Francisca Gigo Cefaly ◽  
Linda Wang ◽  
Liliam Lucia Carrara Paes de Mello ◽  
Janaína Lima dos Santos ◽  
Jean Rodrigo dos Santos ◽  
...  
Keyword(s):  
Water Sorption ◽  
Resin Composite ◽  
Composite Resins ◽  
Glass Ionomer Cements ◽  
Glass Ionomer ◽  
Constant Mass ◽  
Light Emitting ◽  
Halogen Light ◽  
Resin Modified Glass Ionomer ◽  
Light Curing

The Light Emitting Diodes (LED) technology has been used to photoactivate composite resins and there is a great number of published studies in this area. However, there are no studies regarding resin-modified glass-ionomer cements (RMGIC), which also need photoactivation. Therefore, the aim of this study was to evaluate water sorption of two RMGIC photoactivated with LED and to compare this property to that obtained with a halogen light curing unit. A resin composite was used as control. Five specimens of 15.0 mm in diameter x 1.0 mm in height were prepared for each combination of material (Fuji II LC Improved, Vitremer, and Filtek Z250) and curing unit (Radii and Optilight Plus) and transferred to desiccators until a constant mass was obtained. Then the specimens were immersed into deionized water for 7 days, weighed and reconditioned to a constant mass in desiccators. Water sorption was calculated based on weight and volume of specimens. The data were analyzed by two-way ANOVA and Tukey test (p < 0.05). Specimens photocured with LED presented significantly more water sorption than those photocured with halogen light. The RMGIC absorbed statistically significant more water than the resin composite. The type of light curing unit affected water sorption characteristics of the RMGIC.

Sorption and Solubility of Composites Cured with Quartz-tungsten Halogen and Light Emitting Diode Light-curing Units

2008 ◽  
Vol 9 (2) ◽  
pp. 73-80 ◽  
Author(s):  
Luci Regina P. Archegas ◽  
Danilo B. M. Caldas ◽  
Rodrigo N. Rached ◽  
Sergio Vieira ◽  
Evelise M. Souza
Keyword(s):  
Water Sorption ◽  
Hybrid Composites ◽  
Light Emitting Diode ◽  
Composite Resins ◽  
Light Sources ◽  
Constant Mass ◽  
Light Emitting ◽  
Quartz Tungsten Halogen ◽  
Light Curing ◽  
Storage Times

Abstract Aim The objective of this study was to evaluate the effect of light polymerization on water sorption and solubility of hybrid composites. Methods and Materials Three composite resins were used to make discs cured with either quartz-tungsten halogen (QTH) or light emitting diode (LED) curing units. The specimens were stored in a desiccator at 37°C and weighted to a constant mass, then immersed in deionized water for different periods of time, and reconditioned until achieving a constant mass. Sorption and solubility were calculated and subjected to analysis of variance (ANOVA) and Tukey tests (p<0.01). Results There were no statistically significant differences between the light sources. Water sorption increased with storage time for all the composites. The lowest sorption was observed for Herculite XRV™, followed by Tetric Ceram™, and Filtek Z250™. Increased storage times reduced the solubility of Filtek Z250™ but did not affect the solubility of Herculite XRV™ and Tetric Ceram™. Conclusion Water sorption and solubility of composites are not affected by the type of polymerization when the same intensity and exposure times are used. Thus, the differences found are probably related to the composition of the materials. Clinical Significance Water sorption and solubility of composites can lead to a shortened service life. However, these properties are not correlated to the type of polymerization. Citation Archegas LRP, Caldas DBM, Rached RN, Vieira S, Souza EM. Sorption and Solubility of Composites Cured with Quartz-tungsten Halogen and Light Emitting Diode Light-curing Units. J Contemp Dent Pract 2008 February;(9)2:073-080.

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

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.

scholarly journals Abrasion resistance of composites polymerized by light-emitting diodes (LED) and halogen light-curing units

2006 ◽  
Vol 17 (1) ◽  
pp. 29-33 ◽  
Author(s):  
Janisse Martinelli ◽  
Fernanda de Carvalho Panzeri Pires-de-Souza ◽  
Luciana Assirati Casemiro ◽  
Camila Tirapelli ◽  
Heitor Panzer
Keyword(s):  
Surface Roughness ◽  
Mass Loss ◽  
Abrasion Resistance ◽  
Composite Resin ◽  
Composite Resins ◽  
Halogen Lamp ◽  
Light Emitting ◽  
Halogen Light ◽  
Light Curing ◽  
Toothbrush Abrasion

This study compared the abrasion resistance of direct composite resins cured by light-emitting diodes (LED) and halogen light-curing units. Twenty specimens (12 mm in diameter; 1.0 mm thick) of each composite resin [TPH (Dentsply); Definite (Degussa); Charisma (Heraus Kulzer)] were prepared using a polytetrafluoroethylene matrix. Ten specimens per material were cured with the LED source and 10 with the halogen lamp for 40 s. The resin discs were polished, submitted to initial surface roughness reading (Ra initial - mum) in a roughness tester and stored in water at 37°C for 15 days. The specimens were weighed (M1) and submitted to simulated toothbrushing using slurry of water and dentifrice with high abrasiveness. After 100 minutes in the toothbrushing simulator, the specimens were cleaned, submitted to a new surface roughness reading (Ra final - mum) and reweighed (M2). Mass loss was determined as the difference between M1 and M2. Data were recorded and analyzed statistically by one-way ANOVA and Tukey Test at 5% significance level. The composite resin with greater size of inorganic fillers (TPH) showed the lowest mass loss and surface roughness means, indicating a higher resistance to toothbrush abrasion (p<0.05). Definite cured with LED presented the least resistance to toothbrush abrasion, showing the highest means of surface roughness and mass loss (p<0.05). The LED source did not show the same effectiveness as the halogen lamp for polymerizing this specific composite resin. When the composite resins were cured a halogen LCU, no statistically significant difference was observed among the materials (p>0.05). It may be concluded that the type of light-curing unit and the resin composition seemed to interfere with the materials' resistance to abrasion.

Surface Hardness Properties of Resin-Modified Glass Ionomer Cements and Polyacid-Modified Composite Resins

2004 ◽  
Vol 5 (4) ◽  
pp. 42-49 ◽  
Author(s):  
Yusuf Ziya Bayindir ◽  
Mehmet Yildiz
Keyword(s):  
Glass Ionomer Cement ◽  
Water Storage ◽  
Surface Hardness ◽  
Composite Resins ◽  
Bottom Surface ◽  
Glass Ionomer Cements ◽  
Glass Ionomer ◽  
Resin Modified Glass Ionomer ◽  
Hardness Values ◽  
Ionomer Cement

Abstract In this study the top and bottom surface hardness of two polyacid-modified composite resins (PMCRs), one resin-modified glass ionomer cement (RMGIC), and one composite resin were evaluated. The affect of water storage on their hardness was also investigated. The study was conducted using four different groups, each having five specimens obtained from fiberglass die molds with a diameter of 5 mm and a height of 2 mm. Measurements were made on the top and bottom surface of each specimen and recorded after 24 hours and again at 60 days. All tested materials showed different hardness values, and the values of top surfaces of the specimens were found to be higher than the bottom surface in all test groups. There was no statistical difference in the Vickers hardness (HV) values when the test specimens were kept in water storage. In conclusion Hytac displayed microhardness values higher than Vitremer and Dyract. We found the order of HV values to be Surfil > Hytac > Dyract > Vitremer, respectively. Vitremer presented the lowest microhardness level and Surfil the highest. Citation Bayindir YZ, Yildiz M. Surface Hardness Properties of Resin-Modified Glass Ionomer Cements and Polyacid-Modified Composite Resins. J Contemp Dent Pract 2004 November;(5)4:042-049.

Wear of Resin Composites Polymerized by Conventional Halogen Light Curing and Light Emitting Diodes Curing Units

2005 ◽  
Vol 288-289 ◽  
pp. 645-648
Author(s):  
Hwan Kim ◽  
Sung Ho Park ◽  
I.Y. Jung ◽  
S.B. Jeon ◽  
Kwon Yong Lee
Keyword(s):  
Light Emitting Diodes ◽  
Composite Resins ◽  
Dental Composite ◽  
Zirconia Ceramic ◽  
Resin Composites ◽  
Light Emitting ◽  
Dental Composite Resins ◽  
Halogen Light ◽  
Significant Difference ◽  
Light Curing

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.

scholarly journals Effect of light curing unit on resin-modified glass-ionomer cements: a microhardness assessment

2009 ◽  
Vol 17 (3) ◽  
pp. 150-154 ◽  
Author(s):  
Daniela Francisca Gigo Cefaly ◽  
Liliam Lucia Carrara Paes de Mello ◽  
Linda Wang ◽  
José Roberto Pereira Lauris ◽  
Paulo Henrique Perlatti D'Alpino
Keyword(s):  
Glass Ionomer Cements ◽  
Glass Ionomer ◽  
Resin Modified Glass Ionomer ◽  
Light Curing ◽  
Effect Of Light

scholarly journals Effects of Different Light Curing Units/Modes on the Microleakage of Flowable Composite Resins

2008 ◽  
Vol 02 (04) ◽  
pp. 240-246 ◽  
Author(s):  
A. Ruya Yazici ◽  
Cigdem Celik ◽  
Berrin Dayangac ◽  
Gul Ozgunaltay
Keyword(s):  
Light Emitting Diode ◽  
In Vitro Study ◽  
Composite Resins ◽  
Light Emitting ◽  
Flowable Composite ◽  
Group I ◽  
Halogen Light ◽  
Light Curing ◽  
The Difference

Objectives: The aim of this in vitro study was to evaluate the influence of different light curing units and modes on microleakage of flowable composite resins.Methods: Eighty Class V cavities were prepared in buccal and lingual surfaces of 40 extracted human premolars with cervical wall located in dentin and the occlusal wall in enamel. These teeth were randomly assigned into two groups (n=20) and restored with different flowable composites; Group I: Esthet-X Flow, Group II: Grandio Flow. Each group was randomly divided into four subgroups; while the samples of the first subgroup were polymerized with conventional Halogen light, the rest of them were polymerized with different curing modes of Light Emitting Diode (LED). The second subgroup was polymerized with fast-curing; the third subgroup with pulse-curing and those of the fourth subgroup with step-curing modes of LED. After the samples were thermocycled and immersed in dye, they were longitudinally sectioned. Dye penetration was assessed under a stereomicroscope. Data were analyzed by Kruskal-Wallis and Mann-Whitney U tests.Results: None of the restorations showed leakage on enamel margins. On dentin margins no significant differences were observed between flowable composite resins polymerized with halogen light (P>.05). While step curing mode of LED presented significant differences between the resins, the difference was insignificant when fast-curing and pulse-curing mode of LED were used. No statistically significant differences were observed between curing units for Esthet-X Flow samples. For Grandio Flow samples, only step-curing mode of LED caused statistically higher leakage scores than halogen and other curing modes of LED (P<.05).Conclusions: The effect of curing units� type and curing mode on flowable composite resin leakage might be material-dependent. (Eur J Dent 2008;2:240-246)

Sign in / Sign up

Export Citation Format

Share Document