Light-Curing Units, Photoinitiators System, and Monomers on Physico-Mechanical Properties of Experimental Composite Resins

The future of manufacturing applications in three-dimensional (3D) printing depends on the improvement and the development of materials suitable for 3D printing technology. This study aims to develop an applicable and convenient protocol for light-curing resin used in 3D industry, which could enhance antibacterial and mechanical properties of polymethyl methacrylate (PMMA) resin through the combination of nano-fillers of surface modified titanium dioxide (TiO2) and micro-fillers of polyetheretherketone (PEEK). PMMA-based composite resins with various additions of TiO2 and PEEK were prepared and submitted to characterizations including mechanical properties, distribution of the fillers (TiO2 or/and PEEK) on the fractured surface, cytotoxicity, antibacterial activity, and blood compatibility assessment. These results indicated that the reinforced composite resins of PMMA (TiO2-1%-PEEK-1%) possessed the most optimized properties compared to the other groups. In addition, we found the addition of 1% of TiO2 would be an effective amount to enhance both mechanical and antibacterial properties for PMMA composite resin. Furthermore, the model printed by PMMA (TiO2-1%-PEEK-1%) composite resin showed a smooth surface and a precise resolution, indicating this functional dental restoration material would be a suitable light-curing resin in 3D industry.

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Influence of the photoactivation mode and the distance of light-curing unit in mechanical properties of silorane and methacrylate based resins.

Journal of Research in Dentistry ◽

10.19177/jrd.v1e42013281-287 ◽

2013 ◽

Vol 1 (4) ◽

pp. 281

Author(s):

Bárbara Malta Neves Oliveira ◽

Renata Pereira ◽

Maria Do Carmo Aguiar Jordão Mainardi ◽

Gláucia Maria Bovi Ambrosano ◽

Débora Alves Nunes Lima ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Composite Resin ◽

Resin Composite ◽

Composite Resins ◽

Bottom Surface ◽

Base Resin ◽

Light Curing ◽

Base Composite

This in vitro work had as aim evaluate the effect of photoactivation mode and the distance of light-curing unit (LCU) in microhardness Knoop (KHN) and the diametrical tensile strength (DTS) of methacrylate and silorane-based resins. Filtek Z250 (methacrylate-based resin) and Filtek P90 (silorane-based resin), both from 3M Espe, were selected for this work. The photoactivation were performed by one of the following modes: Valo (Ultradent) at 1000 mW/cm2 X 18 s (S); 1400 mW/cm2 X 12 s (HP); 3200 mW/cm2 X 6 s (PE); and XL 3000 (3M Espe) at 450 mW/cm2 X 40 s (XL). Resin composite were inserted in one increment into a bipartide Teflon matrix (5mm X 2mm) and photoactivated at 0mm, 3 or 6mm from the increment surface, according to the experimental groups. After the confection, the specimens (n=5) were submitted to KHN on the top (T) and on the bottom (B), and to DTS. Data were analyzed through ANOVA/Tukey tests (α=5%). It was observed that Filtek Z250 presented values of KHN equal or higher than Filtek P90. The surface T presented higher values of KHN than B. For both composite resins, the values of KHN on the surface B were lower, as higher the distance of LCU. In relation to DTS, the higher values were observed in Filtek Z250. Silorane base composite resin presented lower mechanical properties when compared to the methacrylate base resin. The distance of LCU is able to influence the microhardness of bottom surface.

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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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Deterioration of Mechanical Properties of Composite Resins

Dental Materials Journal ◽

10.4012/dmj.14.78 ◽

1995 ◽

Vol 14 (1) ◽

pp. 78-83,104 ◽

Cited By ~ 15

Author(s):

Hiroyuki ARIKAWA ◽

Hiroyuki KUWAHATA ◽

Hideo SEKI ◽

Takahito KANIE ◽

Koichi FUJII ◽

...

Keyword(s):

Mechanical Properties ◽

Composite Resins

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

Brazilian Oral Research ◽

10.1590/s1806-83242006000400011 ◽

2006 ◽

Vol 20 (4) ◽

pp. 342-346 ◽

Cited By ~ 11

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.

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

Brazilian Dental Journal ◽

10.1590/s0103-64402006000100007 ◽

2006 ◽

Vol 17 (1) ◽

pp. 29-33 ◽

Cited By ~ 8

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.

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