Oxygen inhibition layer of composite resins: effects of layer thickness and surface layer treatment on the interlayer bond strength

The aim of the present study was to investigate and compare the quantity of residual monomers leached from the bulk-fill composites with different compositions polymerized at varying layer thickness. Three bulk-fill (X-tra-fil, Beautifil Bulk Restorative, Fill-Up) and a nanohybrid composite (Filtek Z550) were used for the study. The composite resin samples were prepared with a stainless steel mold. For each composite, two groups were constructed. The samples in the first group were prepared using the 2 + 2 mm layering technique. In the second group, the composite samples were applied as a 4 mm-thick one layer and polymerized. Then, each composite samples were kept in a 75% ethanol solution and residual monomers released from composite resins were analyzed with an HPLC device after 24hour and 1 month. The data were analyzed using Kruskal-Wallis and Mann-Whitney U tests. Except the Fill-Up, all of residual monomer elution from the bulk-fill composites was significantly affected by the layer thickness (p < 0.05). The greatest monomer release was detected at 1 month after polymerization as a single 4 mm layer for Beautifil Bulk Restorative. Fill-Up composite showed similar residual monomer release in polymerization at different layer thicknesses compared to other composite resins. In the 2 + 2 mm layering technique, the least monomer elution was detected in the Filtek Z550 composite group. While Bis-GMA was the most released monomer in X-tra fil composite, UDMA was the most released monomer in all other composite resins. During polymerization of the bulk-fill composite, the layer thickness of the composite applied may affect the amount of residual monomers released from the composite resins. Conventional composites may release less monomer than bulk-fill composites when used with layering.

Download Full-text

Interfacial Fracture Toughness Comparison of Three Indirect Resin Composites to Dentin and Polyether Ether Ketone Polymer

European Journal of Dentistry ◽

10.1055/s-0040-1713309 ◽

2020 ◽

Vol 14 (03) ◽

pp. 456-461

Author(s):

Rayhaneh Khalesi ◽

Mahdi Abbasi ◽

Zahra Shahidi ◽

Masoumeh Hasani Tabatabaei ◽

Zohreh Moradi

Keyword(s):

Fracture Toughness ◽

Bond Strength ◽

Testing Machine ◽

Composite Resins ◽

High Wear Resistance ◽

Luting Cements ◽

Anterior Teeth ◽

Polyether Ether Ketone ◽

Ether Ketone

Abstract Objectives Advances in laboratory composites and their high wear resistance and fracture toughness have resulted in their growing popularity and increasing use for dental restorations. This study sought to assess the fracture toughness of three indirect composites bonded to dental substrate and polyether ether ketone (PEEK) polymer. Materials and Methods This in vitro study was conducted on two groups of dental and polymer substrates. Each substrate was bonded to three indirect composite resins. Sixty blocks (3 × 3 × 12 mm) were made of sound bovine anterior teeth and PEEK polymer. Sixty blocks (3 × 3 × 12 mm) were fabricated of CRIOS (Coltene, Germany), high impact polymer composite (HIPC; Bredent, Germany), and GRADIA (Indirect; GC, Japan) composite resins. Composites were bonded to dentin using Panavia F 2.0 (Kuraray, Japan). For bonding to PEEK, Combo.lign (Bredent) and Visio.Link (Bredent) luting cements were used. In all samples, a single-edge notch was created by a no. 11 surgical blade at the interface. The samples were subjected to 3,500 thermal cycles, and their fracture toughness was measured in a universal testing machine (Zwick/Roell, Germany) by application of four-point flexural load. Statistical Analysis Data were analyzed using one-way analysis of variance, Kruskal–Wallis. Results The fracture toughness of CRIOS–PEEK interface was significantly higher than HIPC–PEEK. The fracture toughness of GRADIA–PEEK was not significantly different from that of HIPC and CRIOS. The fracture toughness of GRADIA–dentin was significantly higher than HIPC–dentin. Conclusion Considering the limitations of this study, GRADIA has the highest bond strength to dentin, while CRIOS shows the highest bond strength to PEEK.

Download Full-text

Effect of Polypropylene Fibre Addition on Properties of Geopolymers Made by 3D Printing for Digital Construction

Materials ◽

10.3390/ma11122352 ◽

2018 ◽

Vol 11 (12) ◽

pp. 2352 ◽

Cited By ~ 41

Author(s):

Behzad Nematollahi ◽

Praful Vijay ◽

Jay Sanjayan ◽

Ali Nazari ◽

Ming Xia ◽

...

Keyword(s):

3D Printing ◽

Bond Strength ◽

Fibre Volume ◽

Interface Plane ◽

Flexural Performance ◽

Fresh State ◽

Hardened State ◽

3D Printed ◽

Shape Retention ◽

Interlayer Bond

This paper investigates the effect of polypropylene (PP) fibres on the fresh and hardened properties of 3D-printed fibre-reinforced geopolymer mortars. Different percentages of PP fibres ranging between 0.25% and 1.00% by volume were added to an optimised geopolymer mixture. All samples showed reasonable workability and extrudability. In addition, shape-retention ability in the fresh state was investigated as a major requirement for 3D-printing. The compressive strength of the printed specimens was tested in the hardened state in three loading directions, viz. longitudinal, perpendicular, and lateral. The flexural strength of samples was also tested in the longitudinal and lateral directions. In addition, the interlayer bond strength was investigated. Fibre addition seems to influence compressive strengths positively only when the loading is perpendicular to the interface plane. This is due to the preferential fibre alignment parallel to the direction of extrusion. The addition of fibre significantly enhanced the flexural performance of the printed samples. The use of fibre dosages of 0.75 and 1.00 vol % caused deflection-hardening behaviour of the 3D-printed geopolymers and, hence, a significantly higher fracture energy in comparison to specimens without fibre or with lower fibre content. However, an increase in the fibre volume caused some minor reduction in interlayer bond strength. With respect to properties in the fresh state, higher fibre volumes caused better shape-retention ability in the printed samples. The results indicate the possibility of printing fibre-reinforced geopolymers which meet all the necessary properties in both the fresh and hardened states.

Download Full-text

Enhanced continuous liquid interface production with track-etched membrane

Rapid Prototyping Journal ◽

10.1108/rpj-12-2017-0251 ◽

2019 ◽

Vol 25 (1) ◽

pp. 117-125 ◽

Cited By ~ 3

Author(s):

Wenxiong Lin ◽

Huagang Liu ◽

Haizhou Huang ◽

Jianhong Huang ◽

Kaiming Ruan ◽

...

Keyword(s):

Pure Oxygen ◽

Inhibition Layer ◽

High Permeability ◽

Content Type ◽

Oxygen Inhibition ◽

Speed Up ◽

Continuous Liquid Interface Production ◽

Track Etched Membrane ◽

Printing Speed ◽

Etched Membrane

PurposeThe purpose of this paper is to explore the possibility of an enhanced continuous liquid interface production (CLIP) with a porous track-etched membrane as the oxygen-permeable window, which is prepared by irradiating polyethylene terephthalate membranes with accelerated heavy ions. Design/methodology/approachExperimental approaches are carried out to characterize printing parameters of resins with different photo-initiator concentrations by a photo-polymerization matrix, to experimentally observe and theoretically fit the oxygen inhibition layer thickness during printing under conditions of pure oxygen and air, respectively, and to demonstrate the enhanced CLIP processes by using pure oxygen and air, respectively. FindingsOwing to the high permeability of track-etched membrane, CLIP process is demonstrated with printing speed up to 800 mm/h in the condition of pure oxygen, which matches well with the theoretically predicted maximum printing speed at difference light expose. Making a trade-off between printing speed and surface quality, maximum printing speed of 470 mm/h is also obtained even using air. As the oxygen inhibition layer created by air is thinner than that by pure oxygen, maximum speed cannot be simply increased by intensifying the light exposure as the case with pure oxygen. Originality/valueCLIP process is capable of building objects continuously instead of the traditional layer-by-layer manner, which enables tens of times improvement in printing speed. This work presents an enhanced CLIP process by first using a porous track-etched membrane to serve as the oxygen permeable window, in which a record printing speed up to 800 mm/h using pure oxygen is demonstrated. Owing to the high permeability of track-etched membrane, continuous process at a speed of 470 mm/h is also achieved even using air instead of pure oxygen, which is of significance for a compact robust high-speed 3D printer.

Download Full-text

Effect of Surface Treatment and Storage Time on Immediate Repair Bond Strength Durability of Methacrylate- and Ormocer-Based Bulk Fill Resin Composites

Applied Sciences ◽

10.3390/app10228308 ◽

2020 ◽

Vol 10 (22) ◽

pp. 8308

Author(s):

Farid S. El-Askary ◽

Sara A. Botros ◽

Mutlu Özcan

Keyword(s):

Bond Strength ◽

Surface Treatment ◽

Shear Bond Strength ◽

Storage Time ◽

Strength Testing ◽

Repair System ◽

Resin Composites ◽

Oxygen Inhibition ◽

And Storage ◽

Effect Of Surface

The aim of this study was to evaluate the effect of surface treatment and storage time on immediate repair bond durability of methacrylate- and ormocer-based bulk fill composites. In total, 265 discs were divided into 32 groups (n = 8/group) according to: (1) Material: X-tra fil and Admira Fusion X-tra; (2) Surface treatment: oxygen inhibition; matrix; Futurabond M+; Silane/Futurabond M+; Admira Bond; Silane/Admira Bond; ceramic repair system; and Silane/Cimara bond; and (3) Storage time: 24 h and 6 months. Each disc received three micro-cylinders from the same material. Specimens were subjected to micro-shear bond strength testing either at 24 h or 6 months. Data were analyzed using ANOVA/Tukey’s test/Student t-test (p = 0.05). All experimental factors had significant effect on bond strength (p < 0.0001). Drop in bond strength was noticed in both materials after six months (p < 0.05), except for Admira Fusion X-tra treated with silane/cimara adhesive (p = 0.860). Both materials showed insignificant values with Admira bond either at 24 h or 6 months (p = 0.275 and p = 0.060, respectively). For other treatments, X-tra fil showed significantly higher values at 24 h and 6 months (p < 0.05). Ceramic repair system can be used to immediately repair both methacrylate- and ormocer-based composites.

Download Full-text

Comparison of Shear Bond Strength and Microleakage of Various Bulk-fill Bioactive Dentin substitutes: An in vitro Study

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-1970 ◽

2016 ◽

Vol 17 (12) ◽

pp. 997-1002 ◽

Cited By ~ 6

Author(s):

Fahad I Alkhudhairy ◽

Zeeshan H Ahmad

Keyword(s):

Bond Strength ◽

Shear Bond Strength ◽

Physical And Mechanical Properties ◽

Pairwise Comparison ◽

In Vitro Study ◽

Composite Resins ◽

Intergroup Comparison ◽

Significant Difference ◽

Tukey Honestly Significant Difference

ABSTRACT Introduction Various bulk-fill materials depending on their composition, viscosity, and flow ability have different physical and mechanical properties. The aim of this in vitro study was to determine and compare the shear bond strength and microleakage properties of activa restorative with other bulk-fill restorative materials surefil (SDR), Biodentine, ever X posterior. Materials and methods Forty permanent premolars were selected for shear bond strength, and 20 permanent premolars were selected with class II cavities on mesial and distal side for microleakage. Universal testing device was used to assess the shear bond strength. Microleakage was checked using dye penetration method under a stereomicroscope. Mean and standard deviation values were calculated from the recorded values. Intergroup comparison was done by one-way analysis of variance (ANOVA) followed by pairwise comparison using Tukey honestly significant difference (HSD) post hoc test. Results The mean shear bond strength was highest for SDR surefil followed by Ever X posterior, Bioactive restorative, and Biodentine respectively. In this study, SDR (surefil) showed better shear bond strength and better microleakage properties compared with the other test materials (F = 186.7157, p < 0.05). Conclusion The result of this study showed that flowable and fiber-reinforced composites have better shear bond strength and microleakage properties. Clinical significance Flowable bulk-fill composite resins can be used as dentin substitutes because of its superior properties. How to cite this article Alkhudhairy FI, Ahmad ZH. Comparison of Shear Bond Strength and Microleakage of Various Bulk-fill Bioactive Dentin substitutes: An in vitro study. J Contemp Dent Pract 2016;17(12):997-1002.

Download Full-text

Correlation between tensile and bond strength of composite resins

European Journal Of Oral Sciences ◽

10.1111/j.1600-0722.1980.tb01237.x ◽

1980 ◽

Vol 88 (4) ◽

pp. 348-351

Author(s):

OMAR ZIDAN ◽

ERIK ASMUSSEN ◽

KNUD DREYER JØRGENSEN

Keyword(s):

Bond Strength ◽

Composite Resins

Download Full-text

Microtensile Bond Strength of Methacrylate and Silorane Resins to Enamel and Dentin

Brazilian Dental Journal ◽

10.1590/0103-6440201300009 ◽

2014 ◽

Vol 25 (4) ◽

pp. 327-331 ◽

Cited By ~ 5

Author(s):

Gisele Rodrigues da Silva ◽

Isabela Sousa Araújo ◽

Rodrigo Dantas Pereira ◽

Bruno de Castro Ferreira Barreto ◽

Célio Jesus do Prado ◽

...

Keyword(s):

Bond Strength ◽

Aging Time ◽

Storage Time ◽

Composite Resin ◽

Glass Plate ◽

Composite Resins ◽

Microtensile Bond Strength ◽

Bonding Interaction ◽

Significant Difference ◽

And Storage

The aim of this study was to evaluate the microtensile bond strength (µTBS) of two substrates (enamel and dentin) considering two study factors: type of composite resin [methacrylate-based (Filtek Supreme) or silorane-based (Filtek LS)] and aging time (24 h or 3 months). Twenty human molars were selected and divided into 2 groups (n=10) considering two dental substrates, enamel or dentin. The enamel and dentin of each tooth was divided into two halves separated by a glass plate. Each tooth was restored using both tested composite resins following the manufacturer's instructions. The samples were sectioned, producing 4 sticks for each composite resin. Half of them were tested after 24 h and half after 3 months. µTBS testing was carried out at 0.05 mm/s. Data were analyzed by three-way ANOVA and Tukey's HSD tests at α=0.05. Significant differences between composite resins and substrates were found (p<0.05), but no statistically significant difference was found for aging time and interactions among study factors. The methacrylate-based resin showed higher µTBS than the silorane-based resin. The µTBS for enamel was significantly higher than for dentin, irrespective of the composite resin and storage time. Three months of storage was not sufficient time to cause degradation of the bonding interaction of either of the composite resins to enamel and dentin.

Download Full-text

Impact of Intracoronal Dentin Treatment Prior to Bleaching on Bond Strength of Restorative Materials

Brazilian Dental Journal ◽

10.1590/0103-6440201302441 ◽

2014 ◽

Vol 25 (6) ◽

pp. 519-523 ◽

Cited By ~ 2

Author(s):

Erica Moreno Zanconato-Carvalho ◽

João Felipe Bruniera ◽

Natália Spadini de Faria ◽

Vivian Colucci ◽

Danielle Cristine Messias

Keyword(s):

Phosphoric Acid ◽

Bond Strength ◽

Surface Treatment ◽

Shear Bond Strength ◽

Composite Resin ◽

Er:Yag Laser ◽

Composite Resins ◽

Bleaching Procedure ◽

Significant Difference ◽

Restorative Materials

Surface treatment of dentin before the bleaching procedure may affect its permeability and influence the bond strength of restorative materials. This study evaluated the influence of surface treatment before the bleaching on shear bond strength (SBT) of restorative materials to intracoronal dentin. Dentin slabs were subjected to surface treatment: no bleaching (control - CON), no surface treatment + bleaching (HP), 37% phosphoric acid + bleaching (PA) and Er:YAG laser + bleaching (L). After the bleaching procedure, specimens (n=10) were restored with: microhybrid composite resin (MH), flowable composite resin (F), and resin-modified glass-ionomer cement (RMGIC). The shear test was carried out. ANOVA and Tukey's test (α=0.05) showed significant difference for surface treatment and restorative materials (p<0.05). CON presented higher STB and was statistically different from HP (p<0.05). PA and L showed intermediate values and were statistically similar to CON and HP (p>0.05). STB for MH and F were higher than RMGIC (p<0.05), and did not differ from each other (p>0.05). The surface treatments with phosphoric acid and Er:YAG laser before the bleaching procedure provided shear bond strength at the same level of unbleached dentin and the composite resins presented superior bond strength to the intracoronal dentin.

Download Full-text