scholarly journals Examining the Effect of Radiant Exposure on Commercial Photopolimerizable Dental Resin Composites

2018 ◽  
Vol 6 (4) ◽  
pp. 55 ◽  
Author(s):  
Carlos Cuevas-Suárez ◽  
Belinda Pimentel-García ◽  
Alejandro Rivera-Gonzaga ◽  
Carlos Álvarez-Gayosso ◽  
Adriana Ancona-Meza ◽  
...  

The objective of this study was to evaluate the effect of radiant exposure on the chemical and physical properties of four commercial dental resin composites. The four dental resin composites used were Kalore, Admira, Tetric N-Ceram Bulk Fill, and Filtek Z350 XT. The composites were subjected to three curing protocols: 1000 mW/cm2 for 5 s, 1000 mW/cm2 for 10 s, and 400 mW/cm2 for 25 s. The flexural strength, elastic modulus, water sorption, water solubility, degree of conversion, and polymerization shrinkage were evaluated. The results were analyzed by means of ANOVA and Tukey tests. For Admira and Kalore, significant differences between light exposure protocols were observed for the elastic modulus (p < 0.001), which was higher when a higher amount of radiant exposure was used. For Filtek Z350, differences were only observed for the degree of conversion (p < 0.001), and a higher amount of radiant exposure allowed us to obtain higher values. The Tetric N-Ceram Bulk Fill analysis showed significant differences for the elastic modulus and water sorption (p < 0.001), and specimens that had been subject to a radiant exposure of 10 J/cm2 showed a higher elastic modulus. In most cases, the physical and mechanical properties analyzed were not affected by different radiant exposure values. Other resin-based composite (RBC) characteristics seem to have a greater influence on material properties.

2017 ◽  
Vol 28 (6) ◽  
pp. 726-730 ◽  
Author(s):  
Caio Vinícius Signorelli Grohmann ◽  
Eveline Freitas Soares ◽  
Eduardo José Carvalho Souza-Junior ◽  
William Cunha Brandt ◽  
Regina Maria Puppin-Rontani ◽  
...  

Abstract The aim in this study was to evaluate the influence of different ratio of camphorquinone/tertiary amine concentration on the flexural strength (FS), elastic modulus (EM), degree of conversion (DC), yellowing (YL), water sorption (WS) and water solubility (WSL) of experimental composites. Thus, acrylate blends were prepared with different camphorquinone (CQ) and amine (DABE) concentrations and ratios by weight: (CQ/DABE%): 0.4/0.4% (C1), 0.4/0.8% (C2), 0.6/0.6% (C3), 0.6/1.2% (C4), 0.8/0.8% (C5), 0.8/1.6% (C6), 1.0/1.0% (C7), 1.0/2.0% (C8), 1.5/1.5% (C9), 1.5/3.0% (C10). For the FS and EM, rectangular specimens (7x2x1 mm, n=10) were photo-activated by single-peak LED for 20 s and tested at Instron (0.5 mm/min). Then, the same specimens were evaluated by FTIR for DC measurement. For YL, disks (5x2 mm, n=10) were prepared, light-cured for 20 s and evaluated in spectrophotometer using the b aspect of the CIEL*a*b* system. For WS and WSL, the volume of the samples was calculated (mm³). For WS and WSL, composites disks (5x0.5 mm, n=5) were prepared. After desiccation, the specimens were stored in distilled water for 7 days and again desiccated, in order to measure the WS and WSL. Data were submitted to one-way ANOVA and Tukey’s test (5%). The groups C8, C9 and C10 showed higher DC, EM and YL means, compared to other composites. Therefore, the FS and WS values were similar among all groups. Also, C1, C2 and C3 presented higher WSL in 7 days, compared to other composites. In general, higher concentrations of camphorquinone promoted higher physical-mechanical properties; however, inducing higher yellowing effect for the experimental composites


2020 ◽  
Vol 4 (2) ◽  
pp. 81 ◽  
Author(s):  
Tejas Barot ◽  
Deepak Rawtani ◽  
Pratik Kulkarni

Objective: The objective of this study was to explore the effect of Chlorhexidine-loaded Halloysite nanotubes (HNT/CHX) fillers (diverse mass fractions from 1 to 10 wt.%) on physicochemical, morphological and biological properties of newly developed experimental dental resin composite, in order to compare with the properties of composites composed of conventional glass fillers. Methods: The dental resin composites were prepared by incorporating various proportions of HNT/CHX. Six different groups of specimens: control group and five groups composed of varied mass fractions of HNT/CHX (e.g., 1.0, 2.5, 5.0, 7.5 and 10 wt.%) as fillers in each group were fabricated. Mechanical properties of the composites were monitored, using UTM. The degree of conversion of dental resin composites and their depth of cure were also evaluated. Antimicrobial properties of dental composites were studied in vitro by applying agar diffusion test on strain Streptococcus mutans and cytotoxicity were studied using NIH-3T3 cell line. Results: The incorporation of varied mass fractions (1.0 to 5.0 wt.%) of HNT/CHX in dental resins composites enhanced mechanical properties considerably with significant antibacterial activity. The slight decrease in curing depth and degree of conversion values of composites indicates its durability. No cytotoxicity was noticed on NIH-3T3 cell lines. Significance: Consistent distribution of HNT/CHX as a filler into dental composites could substantially improve not only mechanical properties but also biological properties of dental composites.


2008 ◽  
Vol 24 (9) ◽  
pp. 1169-1177 ◽  
Author(s):  
Luis Felipe J. Schneider ◽  
Carmem S.C. Pfeifer ◽  
Simonides Consani ◽  
Scott A. Prahl ◽  
Jack L. Ferracane

2013 ◽  
Vol 745-746 ◽  
pp. 466-472 ◽  
Author(s):  
Feng Wei Liu ◽  
Jing Hang Hu ◽  
Rui Li Wang ◽  
Ying Ying Pan ◽  
Xiao Ze Jiang ◽  
...  

Hydroxyapatite (HAP), as an essential component of bone and tooth, is one of the promising bioactive materials. The purpose of this study was to investigate the effects of incorporation of nanoHAP and SiO2 particles on the properties of bioactive dental composite. Silanized HAP and SiO2 were mixed with BisGMA/TEGDMA (1/1 wt/wt) monomers at various HAP/SiO2 mass ratios of 0:7 (no HAP), 5.25/1.75, 3.5/3.5, 1.75/5.25, 7:0 (no SiO2) to yield a series of pastes all containing 70 wt% filler loading. The results showed that flexural strength, elastic modulus and compressive strength gradually decreased with increasing amount of HAP particles, as well as curing depth and polymerization shrinkage, which resulted from the nature of HAP particle material. Water sorption and solubility in water increased slightly with addition of HAP particles. Degree of conversion test could support results above well. Remineralization test in SBF demonstrated dental composite with HAP particles had a good apatite-forming ability. Consequently, dental composite filled with lower amount of nanoHAP (HAP/SiO2 around 0.25) particles would possess better comprehensive performances.


2019 ◽  
Vol 64 (11) ◽  
pp. 1007-1014
Author(s):  
Tong XU ◽  
◽  
Jia-Hui ZHANG ◽  
Zhao-Ying LIU ◽  
Xuan LI ◽  
...  

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2817
Author(s):  
Biao Yu ◽  
Jingwei He ◽  
Sufyan Garoushi ◽  
Pekka K. Vallittu ◽  
Lippo Lassila

In order to improve the toughness and reduce polymerization shrinkage of traditional bisphenol A-glycidyl methacrylate (Bis-GMA)/triethylene glycol dimethacrylate (TEGDMA) based dental resin system, a hyperbranched thiol oligomer (HMDI-6SH) was synthesized via thiol-isocyanate click reaction using pentaerythritol tetra(3-mercaptopropionate (PETA) and dicyclohexylmethane 4,4′-diisocyanate (HMDI) as raw materials. Then HMDI-6SH was mixed with 1,3,5-Triallyl-1,3,5-Triazine-2,4,6(1H,3H,5H)-Trione (TTT) to prepare thiol-ene monomer systems, which were added into Bis-GMA/TEGDMA resins with different mass ratio from 10 wt% to 40 wt% to serve as anti-shrinking and toughening agent. The physicochemical properties of these thiol-ene-methacrylate ternary resins including functional groups conversion, volumetric shrinkage, flexural properties, water sorption, and water solubility were evaluated. The results showed that the incorporation of HMDI/TTT monomer systems into Bis-GMA/TEGDMA based resin could improve C=C double bond conversion from 62.1% to 82.8% and reduced volumetric shrinkage from 8.53% to 4.92%. When the mass fraction of HMDI/TTT monomer systems in the resins was no more than 20 wt%, the flexural strength of the resin was higher or comparable to Bis-GMA/TEGDMA based resins (p > 0.05). The toughness (it was measured from the stress–strain curves of three-point bending test) of the resins was improved. Water sorption and water solubility tests showed that the hydrophobicity of resin was enhanced with increasing the content of thioester moiety in resin.


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