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  1. Fulltext Crystal structure of 5-[4-(di-methyl-amino)-phen-yl]-3-(4-methyl-phen-yl)-4,5-di-hydro-1H-pyrazole-1-carbaldehyde
    Adam F, Samshuddin S, Ameram N, Subramaya, Samartha L
    Acta Crystallogr E Crystallogr Commun, 2015 Dec 1;71(Pt 12):o1031-2.
    PMID: 26870482 DOI: 10.1107/S2056989015023294
    The title compound, C19H21N3O, comprises a central pyrazole ring which is N-connected to an aldehyde group and C-connected twice to substituted benzene rings. The pyrazole ring is twisted on the C-C single bond, and the least-squares plane through this ring forms dihedral angles of 82.44 (5) and 4.52 (5)° with the (di-methyl-amino)-benzene and p-tolyl rings, respectively. In the crystal, weak C-H⋯O hydrogen bonds link mol-ecules into supra-molecular tubes along the b axis.
    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate
  2. Fulltext Bond strengths of composite resins used for the attachment of bonded retainers
    Sinniah, Saraswathy D., Jones, Steven P., Georgiou, George, Cunningham, Susan J., Petrie, Aviva
    Compendium of Oral Science, 2016;3(1):17-24.
    MyJurnal
    used with bonded retainers. Setting: Department of Orthodontics, UCL Eastman Dental Institute, United Kingdom. Methods: Flowable composite resins (Transbond TM Supreme LV, StarFlowTM and Tetric EvoFlow®) and non -flowable control resin (TransbondTM LR) were made into cylinders prior to bonding to hydoxyapatite discs. They were then mounted into jigs and tested in the InstronTM Universal Testing Machine in both shear and tensile modes. Results: The highest mean shear bond strength was seen with StarFlow TM (14.09 MPa), which was significantly higher than both TransbondTM LR (9.48 MPa) and TransbondTM Supreme LV (8.20 MPa). The mean shear bond strength of Tetric EvoFlow® (11.86 MPa) was also significantly higher than TransbondTM Supreme LV. The highest mean tensile bond strength was seen with Tetric EvoFlow® (2.14 MPa), which was significantly higher than TransbondTM LR (1.15 MPa) and TransbondTM Supreme LV (0.61 MPa) but not significantly different to StarFlowTM (1.47 MPa). For shear loading, StarFlowTM had the highest 50th percentile survival estimate at 15.10 MPa, followed by Tetric EvoFlow® (13.00 MPa) and TransbondTM Supreme LV (7.50 MPa). TransbondTM LR had a 50th percentile estimate at 9.00 MPa. For tensile loading, Tetric EvoFlow® had the highest 50th percentile survival estimate at 2.50 MPa, followed by StarFlowTM (1.30 MPa) and TransbondTM Supreme LV (0.50 MPa). TransbondTM LR had a 50th percentile estimate at 1.00 MPa. Conclusions: Mean shear bond strengths for all of the resins were significantly higher than the mean tensile bond strengths. StarFlowTM and Tetric EvoFlow® could potentially be suitable clinical alternatives to TransbondTM LR due to its low viscosity flow characteristics and adequate shear and tensile bond strengths.
    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate
  3. Fulltext The effect of different dental adhesive systems on hybrid layer qualities
    SH, Ku, YS, Tan, Yahya NA
    Ann Dent, 2014;21(1):25-32.
    MyJurnal
    The study aimed to evaluate the quality of the hybrid
    layer form by three different adhesive systems. Class V
    cavities were prepared on the buccal surface of fourty
    extracted human premolars. The prepared teeth were
    randomly assigned into four groups according to the
    adhesive system and application mode. The systems
    were: Optibond S (OS, total-etch); Optibond Versa (OV,
    two-bottles, self-etch); Single Bond Universal (SBU,
    one-bottle, self-etch) and Single Bond Universal with
    etchant (SBU + etchant). All cavities were restored with
    composite (Filtek Z350XT). The samples were sectioned,
    polished and pretreated to remove minerals, protein
    and water prior to SEM evaluation. From the images,
    thickness of the hybrid layers was measured. Present of
    resin tags and adaptation failure were also recorded. The
    data obtained were analyzed using ANOVA, Dunnett’s
    T3, Kruskal-Wallis and Mann-Whitney tests. OS group
    showed the highest average hybrid layer thickness (4.34
    µm), followed by SBU + etchant (3.06 µm), OV (1.91 µm)
    and SBU (0.95 µm). Both adhesive and cohesive failures
    were observed in SBU group. Present of prominent resin
    tags were seen in both OS and OV groups. In conclusion,
    all the investigated adhesive systems were able to perform
    distinguishable actions as shown in micro-morphological
    alteration and hybrid layer thickness. Two-bottles, selfetch
    adhesive (OV) was proven to produce negligible
    adaptation failure compared to other adhesive systems in
    the present study. Combined all-in-one adhesive (SBU)
    was found to render a superior bonding performance in
    total-etch mode comparing to self-etch mode.
    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate
  4. Fulltext Surface Energy Mapping of Modified Silica Using IGC Technique at Finite Dilution
    Ngeow YW, Williams DR, Chapman AV, Heng JYY
    ACS Omega, 2020 May 12;5(18):10266-10275.
    PMID: 32426583 DOI: 10.1021/acsomega.9b03920
    The reinforcing silica filler, which can be more than 40% of an elastomer composite, plays a key role to achieve the desired mechanical properties in elastomer vulcanizates. However, the highly hydrophilic nature of silica surface causes silica particle aggregation. It remained a challenge for many tire manufacturers when using silica-filled elastomer compounds. Here, the silica surface energy changes when the surface is modified with coupling or noncoupling silanes; coupling silanes can covalently bond the silica to the elastomers. The surface energy of silica was determined using inverse gas chromatography (IGC) at finite dilution (FD-IGC) and found to be reduced by up to 50% when the silica surface was silanized. The spatial distribution of silica aggregates within the tire matrix is determined by transmission electron microscopy (TEM) and a direct correlation between aggregate size (silica microdispersion) and work of cohesion from IGC is reported, highlighting surface energy and work of cohesion being excellent indicators of the degree of dispersion of silica aggregates.
    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate
  5. Degree of conversion and physicomechanical properties of newly developed flowable composite derived from rice husk using urethane dimethacrylate monomer
    Azlisham NAF, Johari Y, Mohamad D, Yhaya MF, Mahmood Z
    Proc Inst Mech Eng H, 2023 Dec;237(12):1339-1347.
    PMID: 38014749 DOI: 10.1177/09544119231208222
    This study evaluated the use of urethane dimethacrylate (UDMA) as a base monomer to prepare the newly developed flowable composite (FC) using nanohybrid silica derived from rice husk in comparison to bisphenol A-glycidyl methacrylate (Bis-GMA) on the degree of conversion and physicomechanical properties. The different loadings of base monomer to diluent monomer were used at the ratio of 40:60, 50:50, and 60:40. The bonding analysis confirmed the presence of nanohybrid silica in the newly developed FC. Independent t-test revealed a statistically significant increase in the degree of conversion, depth of cure and Vickers hardness of the UDMA-based FC, while surface roughness showed comparable results between the two base monomers. In conclusion, UDMA-based FC demonstrated superior performance with 60%-65% conversions, a significantly higher depth of cure exceeding 1 mm which complies with the Internal Standard of Organization 4049 (ISO 4049), and a substantial increase in Vickers hardness numbers compared to Bis-GMA-based FC, making UDMA a suitable alternative to Bis-GMA as a base monomer in the formulation of this newly developed FC derived from rice husk.
    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate
  6. Fulltext Effect of delayed light-cured activation on bond-strengths between composites and adhesives
    Masudi, S.M., Padtong, E.A.
    Archives of Orofacial Sciences, 2006;1(1):36-41.
    MyJurnal
    The objective of this study was to evaluate and compare the effect of times elapsed on the application of a single-step adhesive system and activation of light cured subsequently placed composite to the bond strength between composites and adhesives. This was an experimental study using fifteen teeth extracted human premolars, which were caries and pathology free. Sample of teeth were embedded up to cemento-enamel junction on box of acrylic resin. All teeth were cut to obtain flat occlusal dentin surfaces. The specimens were randomly selected and divided into three groups with five teeth each. All the teeth were assigned to single-step bonding system AQ Bond (Sun Medical Co. Ltd., Shiga, Japan) according to manufacturer’s direction. Group 1 was left for 45 seconds, group 2 for 2 minutes, while group 3 was 5 minutes before putting subsequently restorative material. Composite resin was applied in 3 mm diameter and 6 mm height of cylinder mold and cured according to manufacturer’s direction on the dentin surface. Shear bond strength were measured using a testing system (Instron 8874, Instron Corp., Canton, MA, USA) at a crosshead speed of 2 mm/min with cell load capacity of 25 KN. The bond-strengths between single step adhesive system (AQ Bond) and light cured composites were tested. Mann-Whitney test showed no significant differences in bond-strength between Group 1 and Group 2. However, there were significantly differences (p
    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate
  7. Fulltext Effect of desensitizing agent on shear bond strength of an adhesive system
    Awang, R.A.R., Masudi, S.M., Mohd Nor, W.Z.W.
    Archives of Orofacial Sciences, 2007;2(1):32-35.
    MyJurnal
    Desensitization of teeth after cavity preparation has been recommended in an attempt to avoid post-operative sensitivity. However, there is concern regarding application effect of desensitizing agent on shear bond strength of the adhesive system used. The purpose of our study was to compare the shear bond strength of adhesive system in two different dentin surface treatments, with and without desensitizing agent. Sixteen extracted human premolars were sectioned off at the coronal portion to expose the flat dentin surfaces. The surfaces were finished using 600 Grit Wet Silicon Carbide abrasive papers. The premolars were randomly assigned to two groups: control and treated with MS Coat desensitizing agent. The desensitizer was applied according to manufacturer’s instruction. Resin composite was bonded to each dentin surface using Prime & Bond ® adhesive system. The composite resin was debonded by shear stress. Mann-Whitney Test was used in statistical analysis. Our result showed that application of MS Coat desensitizing agent on dentin surface had significantly reduced the shear bond strength of the adhesive system used (z = - 0.14, p < 0.05). Thus, we conclude that shear bond strength of Prime & Bond ® NT (Dentsply, USA) adhesive system will be reduced if dentin surface is treated with MS Coat (Sun Medical, Japan) desensitizing agent.
    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate
  8. Fulltext Co-Blend Application Mode of Bulk Fill Composite Resin
    Al-Nabulsi M, Daud A, Yiu C, Omar H, Sauro S, Fawzy A, et al.
    Materials (Basel), 2019 Aug 07;12(16).
    PMID: 31394743 DOI: 10.3390/ma12162504
    Objective: To evaluate the effect of a new application method of bulk-fill flowable composite resin material on bond-strength, nanoleakage, and mechanical properties of dentine bonding agents.

    MATERIALS AND METHODS: Sound extracted human molars were randomly divided into: manufacturer's instructions (MI), manual blend 2 mm (MB2), and manual blend 4 mm (MB4). Occlusal enamel was removed and flattened, dentin surfaces were bonded by Prime & Bond universal (Dentsply and Optibond FL, Kerr). For the MI group, adhesives were applied following the manufacturer's instructions then light-cured. For MB groups, SDR flow+ bulk-fill flowable composite resin was applied in 2- or 4-mm increment then manually rubbed by a micro brush for 15 s with uncured dentine bonding agents and the mixture was light-cured. Composite buildup was fabricated incrementally using Ceram.X One, Dentsply nanohybrid composite resin restorative material. After 24-h water storage, the teeth were sectioned to obtain beams of about 0.8 mm2 for 24-h and thermocycled micro-tensile bond strength at 0.5 mm/min crosshead speed. Degree of conversion was evaluated with micro-Raman spectroscopy. Contraction gaps at 24 h after polymerization were evaluated and atomic force microscopy (AFM) nano-indentation processes were undertaken for measuring the hardness across the interface. Depth of resin penetration was studied using a scanning electron microscope (SEM). Bond strength data was expressed using two-way ANOVA followed by Tukey's test. Nanoindentation hardness was separately analyzed using one-way ANOVA.

    RESULTS: Factors "storage F = 6.3" and "application F = 30.11" significantly affected the bond strength to dentine. For Optibond FL, no significant difference in nanoleakage was found in MI/MB4 groups between baseline and aged specimens; significant difference in nanoleakage score was observed in MB2 groups. Confocal microscopy analysis showed MB2 Optibond FL and Prime & Bond universal specimens diffusing within the dentine. Contraction gap was significantly reduced in MB2 specimens in both adhesive systems. Degree of conversion (DC) of the MB2 specimens were numerically more compared to MS1 in both adhesive systems.

    CONCLUSION: Present study suggests that the new co-blend technique might have a positive effect on bond strengths of etch-and-rinse adhesives to dentine.

    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate
  9. Fulltext Effect of luting cement to push-out bond strength of fibre reinforced post
    Yahya, N.A., Lui, J.L., Chong, K.W.A., Abu Kasim, N.H., Radzi, Z., Lim, C.M.
    Ann Dent, 2008;15(1):11-19.
    MyJurnal
    The objective of this study was to investigate the effect of various luting cement systems on bond strength of fibre-reinforced posts to root canal dentine. 40 extracted single rooted sound premolar teeth were root filled, decoronated and randomly divided into four groups. Fibre posts, Aestheti- Plus™ (Bisco,Inc. Schaumburg, IL, USA) were cemented using four luting cements: Group A (control): Elite 100® Zinc phosphate (GC Corp, Japan), Group B: Calibra ™ Esthetic Resin Cement (Dentsply Caulk, USA), Group C: RelyX ARC Adhesive Resin (3M ESPE), Group D: RelyX Unicem Aplicap (3M ESPE). Each root was sliced into 2 discs representing the coronal and middle portions of the root canal giving rise to 20 specimens per group. Bond strength was determined using push-out tests and data was analyzed using SPSS version 14.0. The mean bond strength of Group A to Aestheti-Plus™ post was 7.71 MPa (±2.51) and Group B was 5.69 MPa (±3.23). Group C exhibited the lowest mean bond strength, 4.29 MPa (±3.53) while the highest bond strength was obtained from Group D, 7.98 MPa (±2.61). One way ANOVA showed significant interaction between all groups (p=.OOI). Post-hoc Bonferroni test reve;iled that bond strength of Group C was significantly lower compared to Group A (p=.008) and D (p=.004). In conclusion, the mean bond strength of Aestheti- Plus™ post to root canal dentine was highest when cemented with RelyX Unicem resin cement followed by Elite 100® zinc phosphate cement, Calibra and RelyX ARC resin cements. However, the bond strengths of Cali bra and RelyX Unicem resin cements were not significantly different from Elite 100® zinc phosphate cement.
    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate
  10. Microleakage assessment of a repaired, nano-filled, resin-based fissure sealant
    Qadri GW, Noor SN, Mohamad D
    Pediatr Dent, 2009 Sep-Oct;31(5):389-94.
    PMID: 19947133
    The purpose of this study was to evaluate the effects of different repairing techniques of a fractured sealant on microleakage in vitro.
    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate
  11. Effect of one-step polishing system on the color stability of nanocomposites
    Alawjali SS, Lui JL
    J Dent, 2013 Aug;41 Suppl 3:e53-61.
    PMID: 23103847 DOI: 10.1016/j.jdent.2012.10.008
    This study was to compare the effect of three different one-step polishing systems on the color stability of three different types of nanocomposites after immersion in coffee for one day and seven days and determine which nanocomposite material has the best color stability following polishing with each of the one-step polishing system.
    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate/chemistry
  12. The effect of filler content and processing variables on dimensional accuracy of experimental composite inlay material
    Razak AA, Harrison A
    J Prosthet Dent, 1997 Apr;77(4):353-8.
    PMID: 9104710
    Dimensional accuracy of a composite inlay restoration is important to ensure an accurate fit and to minimize cementation stresses.
    Matched MeSH terms: Bisphenol A-Glycidyl Methacrylate/chemistry
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