Displaying publications 1 - 20 of 141 in total

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  1. Walle KZ, Musuvadhi Babulal L, Wu SH, Chien WC, Jose R, Lue SJ, et al.
    ACS Appl Mater Interfaces, 2021 Jan 20;13(2):2507-2520.
    PMID: 33406841 DOI: 10.1021/acsami.0c17422
    Although solid-state Li-metal batteries (LMBs) featuring polymer-based solid electrolytes might one day replace conventional Li-ion batteries, the poor Li-ion conductivity of solid polymer electrolytes at low temperatures has hindered their practical applications. Herein, we describe the first example of using a co-precipitation method in a Taylor flow reactor to produce the metal hydroxides of both the Ga/F dual-doped Li7La3Zr2O12 (Ga/F-LLZO) ceramic electrolyte precursors and the Li2MoO4-modified Ni0.8Co0.1Mn0.1O2 (LMO@T-LNCM 811) cathode materials for LMBs. The Li/Nafion (LiNf)-coated Ga/F-LLZO (LiNf@Ga/F-LLZO) ceramic filler was finely dispersed in the poly(vinylidene fluoride)/polyacrylonitrile/lithium bis(trifluoromethanesulfonimide)/succinonitrile matrix to give a trilayer composite polymer electrolyte (denoted "Tri-CPE") through a simple solution-casting. The bulk ionic conductivity of the Tri-CPE at room temperature was approximately 4.50 × 10-4 S cm-1 and exhibited a high Li+ ion transference number (0.84). It also exhibits a broader electrochemical window of 1-5.04 V versus Li/Li+. A full cell based on a CR2032 coin cell containing the LMO@T-LNCM811-based composite cathode, when cycled under 1 C/1 C at room temperature for 300 cycles, achieved an average Columbic efficiency of 99.4% and a capacity retention of 89.8%. This novel fabrication strategy for Tri-CPE structures has potential applications in the preparation of highly safe high-voltage cathodes for solid-state LMBs.
    Matched MeSH terms: Ceramics
  2. Hashim SM, Mohamed AR, Bhatia S
    Adv Colloid Interface Sci, 2010 Oct 15;160(1-2):88-100.
    PMID: 20813344 DOI: 10.1016/j.cis.2010.07.007
    There has been tremendous progress in membrane technology for gas separation, in particular oxygen separation from air in the last 20 years. It provides an alternative route to the existing conventional separation processes such as cryogenic distillation and pressure swing adsorption as well as cheaper production of oxygen with high purity. This review presents the recent advances of ceramic membranes for the separation of oxygen from air at high temperature. It covers the issues and problems with respect to the selectivity and separation performance. The paper also presents different approaches applied to overcome these challenges. The future directions of ceramic-based membranes for oxygen separation from air are also presented.
    Matched MeSH terms: Ceramics/chemistry*
  3. Yahya, N.A., Lim, K.H.D.
    Ann Dent, 2008;15(2):89-93.
    MyJurnal
    Direct composite veneers can be used to mask tooth discolorations and/or to correct unaesthetic tooth forms and/or positions. However, these type of restorations are often regarded as one of the most challenging in aesthetic dentistry presumably due to the extent of natural tooth structure that must be recreated. This paper discusses easy application techniques and tips for Ceram.X Duo™, a nano ceramic composite restorative material. Its natural shading system allows the restoration of tooth with both dentine and enamel shade and transforms it into a final direct veneer restoration that mimics a natural tooth.
    Matched MeSH terms: Ceramics
  4. Ahmad, R., Wu, B.W., Morgano, S.M.
    Ann Dent, 2001;8(1):-.
    MyJurnal
    Polishing of dental ceramics has become an increasingly important procedure in restorative dentistry as allceramic restorations, which require post-cementation occlusal adjustment, are gaining in popularity. There are numerous studies in both dental and ceramic literature on polishing of dental ceramics and the effects of polishing on their mechanical properties. However, lack of standardization in polishing parameters, precludes comparison among these studies. A clear understanding is lacking of the relative roles and interdependence of handpiece speed, abrasive characteristic, and polishing load. This paper will discuss the mechanism of polishing and review the literature on polishing and its effect on the mechanical properties of ceramic restorations.
    Matched MeSH terms: Ceramics
  5. Khan, A., Mohd Noor, N.S., Sukumaran, P., Sheikh Aladin, S.H.A., Wai Ying, Y.
    Ann Dent, 2016;22(2):1-8.
    MyJurnal
    This clinical audit is aimed to provide an insight into the performance of dental technicians in rendering
    fixed prosthodontics services at Faculty of Dentistry, University of Malaya. A retrospective audit was
    carried out between 1st of November 2014 and 31st January 2015 using data derived from records and
    monthly returns of the technicians, which are kept at the ceramic laboratory. Retrospective data on
    cases of diagnostic wax-ups, full metal crowns, metal ceramic crowns, all ceramic crowns and bridges
    that were sent to ceramic laboratory for fabrication from 1st of September 2013 to 31st of August 2014
    was systematically extracted from the record and tabulated categorically in SPSS version 22.0. The
    turnaround time in workings day for diagnostic wax-ups and the prostheses was calculated by deducting
    exit date from entry date. Subsequently, the turnaround time and the complexity of cases were categorized
    accordingly. The association of turnaround time and the complexity of the cases was analysed using
    Fisher Exact test with p value < 0.05. Within this time frame, a total of 102 cases of diagnostic waxups,
    36 cases of crown and 18 cases of bridges were fabricated. 57.8% of diagnostic wax-ups were
    completed within 3 days. 100% of 1 unit crown were completed within 7 days and 94.4% of bridges were
    completed within 14 days. There was a significant association of turnaround time and the complexity of
    the cases for diagnostic wax-ups and crowns with p value
    Matched MeSH terms: Ceramics
  6. Munusamy SM, Helen-Ng LC, Farook MS
    BMC Oral Health, 2024 Feb 01;24(1):162.
    PMID: 38302972 DOI: 10.1186/s12903-024-03905-7
    BACKGROUND: Computer-aided design/computer-aided manufacturing (CAD/CAM) dental composites were introduced with superior mechanical properties than conventional dental composites. However, little is known on effects of dietary solvents on microhardness or inorganic elemental composition of CAD/CAM composites.

    OBJECTIVES: The objectives of this study were to evaluate the degradation effects of each dietary solvent on the microhardness of the different CAD/CAM dental composites and to observe the degradation effects of dietary solvent on the inorganic elements of the dental composites investigated.

    METHODS: Fifty specimens with dimensions 12 mm x 14 mm x 1.5 mm were prepared for direct composite (Filtek Z350 XT [FZ]), indirect composite (Shofu Ceramage [CM]), and three CAD/CAM composites (Lava Ultimate [LU], Cerasmart [CS], and Vita Enamic [VE]). The specimens were randomly divided into 5 groups (n = 10) and conditioned for 1-week at 37°C in the following: air (control), distilled water, 0.02 N citric acid, 0.02 N lactic acid and 50% ethanol-water solution. Subsequently, the specimens were subjected to microhardness test (KHN) using Knoop hardness indenter. Air (control) and representative postconditioning specimens with the lowest mean KHN value for each material were analyzed using energy dispersive X-ray spectroscopy (EDX). Statistical analysis was done using one-way ANOVA and post hoc Bonferroni test at a significance level of p = 0.05.

    RESULTS: Mean KHN values ranged from 39.7 ± 2.7 kg/mm2 for FZ conditioned in 50% ethanol-water solution to 79.2 ± 3.4 kg/mm2 for VE conditioned in air (control). With exception to LU, significant differences were observed between materials and dietary solvents for other dental composites investigated. EDX showed stable peaks of the inorganic elements between air (control) and representative postconditioning specimens.

    CONCLUSIONS: The microhardness of dental composites was significantly affected by dietary solvents, except for one CAD/CAM composite [LU]. However, no changes were observed in the inorganic elemental composition of dental composites between air (control) and 1-week postconditioning.

    Matched MeSH terms: Ceramics*
  7. Abd Samad H, Jaafar M, Othman R, Kawashita M, Abdul Razak NH
    Biomed Mater Eng, 2011;21(4):247-58.
    PMID: 22182792 DOI: 10.3233/BME-2011-0673
    In present study, a new composition of glass-ceramic was synthesized based on the Na2O-CaO-SiO2-P2O5 glass system. Heat treatment of glass powder was carried out in 2 stages: 600 °C as the nucleation temperature and different temperature on crystallization at 850, 950 and 1000 °C. The glass-ceramic heat-treated at 950 °C was selected as bioactive filler in commercial PMMA bone cement; (PALACOS® LV) due to its ability to form 2 high crystallization phases in comparison with 850 and 1000 °C. The results of this newly glass-ceramic filled PMMA bone cement at 0-16 wt% of filler loading were compared with those of hydroxyapatite (HA). The effect of different filler loading on the setting properties was evaluated. The peak temperature during the polymerization of bone cement decreased when the liquid to powder (L/P) ratio was reduced. The setting time, however, did not show any trend when filler loading was increased. In contrast, dough time was observed to decrease with increased filler loading. Apatite morphology was observed on the surface of the glass-ceramic and selected cement after bioactivity test.
    Matched MeSH terms: Ceramics/chemical synthesis*; Ceramics/chemistry*
  8. Ng MH, Duski S, Tan KK, Yusof MR, Low KC, Rose IM, et al.
    Biomed Res Int, 2014;2014:345910.
    PMID: 25165699 DOI: 10.1155/2014/345910
    Calcium phosphate-based bone substitutes have not been used to repair load-bearing bone defects due to their weak mechanical property. In this study, we reevaluated the functional outcomes of combining ceramic block with osteogenic-induced mesenchymal stem cells and platelet-rich plasma (TEB) to repair critical-sized segmental tibial defect. Comparisons were made with fresh marrow-impregnated ceramic block (MIC) and partially demineralized allogeneic bone block (ALLO). Six New Zealand White female rabbits were used in each study group and three rabbits with no implants were used as negative controls. By Day 90, 4/6 rabbits in TEB group and 2/6 in ALLO and MIC groups resumed normal gait pattern. Union was achieved significantly faster in TEB group with a radiological score of 4.50 ± 0.78 versus ALLO (1.06 ± 0.32), MIC (1.28 ± 0.24), and negative controls (0). Histologically, TEB group scored the highest percentage of new bone (82% ± 5.1%) compared to ALLO (5% ± 2.5%) and MIC (26% ± 5.2%). Biomechanically, TEB-treated tibiae achieved the highest compressive strength (43.50 ± 12.72 MPa) compared to those treated with ALLO (15.15 ± 3.57 MPa) and MIC (23.28 ± 6.14 MPa). In conclusion, TEB can repair critical-sized segmental load-bearing bone defects and restore limb function.
    Matched MeSH terms: Ceramics/pharmacology
  9. Usman J, Salami BA, Gbadamosi A, Adamu H, Usman AG, Benaafi M, et al.
    Chemosphere, 2023 Aug;331:138726.
    PMID: 37116721 DOI: 10.1016/j.chemosphere.2023.138726
    Due to the significant energy and economic losses brought on by the global oil spill, there has been an increased interest in oil-water separation. This study presents strong non-linear machine learning models (support vector regression (SVR) and Gaussian process regression (GPR)) with the Response surface method (RSM) to predict the oil flux and oil-water separation efficiency of wastewater using ceramic membrane technology. For the model development and prediction of oil flux (OF) and oil-water separation efficiency (OSE), oil concentration (mg/L), feed flow rate (mL/min), and pH were considered as input variables. The input variables are combined in three combinations to study the most contributing input features to the models' performance. Mean square error (MSE) and Nash-Sutcliffe coefficient efficiency (NSE) were used to assess the prediction performances of the developed models with the different number of input combinations considered in the study. For the two target variables (OF and OSE), GPR and SVR models were used to separately predict them. For OF, the SVR-2 [Combo-2] model (MSE = 0.9255 and NSE = 2.7976) performed better with higher prediction accuracy compared to GPR-2 [Combo-2] model (MSE = 0.763 and NSE = 6.437). In addition, for OSE, the GPR-3 [Combo-3] model (MSE = 0.995 and NSE = 0.5544) performed slightly better than SVR-3 [Combo-3] model (MSE = 0.992 and NSE = 0.8066). The results showed that the SVR model with the combo-2 and GPR-3 models for OF and OSE variables are the proposed models with the best performance and accuracy. This machine learning study will aid in better evaluating the function of materials such as ceramic in membrane performance features such as oil flux and rejection prediction, separation efficiency, water recovery, membrane fouling, and so on. As for academics and manufacturers, this machine learning (ML) strategy will boost performance and allow a better understanding of system governance.
    Matched MeSH terms: Ceramics
  10. Siti Mariam Ab Ghani, Ahmad Syahir Ahmad Zu Saifudin, Muhammad Aliff Ikram Noor Zari, Teh Adilla Mustaza
    Compendium of Oral Science, 2015;2(1):47-51.
    MyJurnal
    Dental fluorosis incidence had been reported to be affecting children widely, especially in water-fluoridated ar-ea. As these children grow into young adults, perceived aesthetic problems arise mainly due to their concern with generalized mottled and stained teeth appearance. Fixed prosthodontics treatment involving single anterior tooth in patients with generalized fluorosis condition had been found challenging due to aesthetic restorability to blend with fluorosis condition. Clinical considerations: A simplified procedural direct chair-side technique of mimicking fluorosis condition onto anterior all-ceramic crowns are discussed in this paper. The mimicked fluoro-sis is reversible and has the opportunity to be adjusted according to the patient’s fluorosis condition thus hinder-ing the need to redo the crown in the future. Conclusions: The appearance of anterior all-ceramic crowns with direct chair-side staining technique provided blended and harmonized well with the dental fluorosis condition in both patients thus, giving natural looking smile.
    Matched MeSH terms: Ceramics
  11. Abdullah AM, Rahim TNAT, Hamad WNFW, Mohamad D, Akil HM, Rajion ZA
    Dent Mater, 2018 11;34(11):e309-e316.
    PMID: 30268678 DOI: 10.1016/j.dental.2018.09.006
    OBJECTIVE: To compare the mechanical and biological properties of newly developed hybrid ceramics filled and unfilled polyamide 12 (PA 12) for craniofacial reconstruction via a fused deposition modelling (FDM) framework.

    METHODS: 15wt% of zirconia (ZrO2) as well as 30, 35, and 40wt% of beta-tricalcium phosphate (β-TCP) were compounded with PA 12, followed by the fabrication of filament feedstocks using a single screw extruder. The fabricated filament feedstocks were used to print the impact specimens. The melt flow rate, tensile properties of fabricated filament feedstocks, and 3D printed impact properties of the specimens were assessed using melt flow indexer, universal testing machine, and Izod pendulum tester, respectively. The microstructure of selected filament feedstocks and broken impact specimens were analysed using a field emission scanning electron microscope and universal testing machine. Human periodontal ligament fibroblast cells (HPdLF) were used to evaluate the cytotoxicity of the materials by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromid) (MTT) assay.

    RESULTS: Hybrid ceramics filled PA 12 indicated sufficient flowability for FDM 3D printing. The tensile strength of hybrid ceramics filled PA 12 filament feedstocks slightly reduced as compared to unfilled PA 12. However, the tensile modulus and impact strength of hybrid ceramics filled PA 12 increased by 8%-31% and 98%-181%, respectively. A significant increase was also detected in the cell viability of the developed composites at concentrations of 12.5, 25, 50 and 100mg/ml.

    SIGNIFICANCE: The newly developed hybrid ceramics filled PA 12 filament feedstock with improved properties is suitable for an FDM-based 3D printer, which enables the creation of patient-specific craniofacial implant at a lower cost to serve low-income patients.

    Matched MeSH terms: Ceramics/toxicity; Ceramics/chemistry*
  12. Cahyanto A, Martins MVS, Bianchi O, Sudhakaran DP, Sililkas N, Echeverrigaray SG, et al.
    Dent Mater, 2023 Sep;39(9):763-769.
    PMID: 37400298 DOI: 10.1016/j.dental.2023.06.009
    OBJECTIVES: to characterize the effects of graphene oxide (GO) on polymethyl methacrylate's (PMMA) reliability and lifetime. The hypothesis tested was that GO would increase both Weibull parameters and decreased strength degradation over time.

    METHODS: PMMA disks containing GO (0.01, 0.05, 0.1, or 0.5 wt%) were subjected to a biaxial flexural test to determine the Weibull parameters (m: modulus of Weibull; σ0: characteristic strength; n = 30 at 1 MPa/s) and slow crack growth (SCG) parameters (n: subcritical crack growth susceptibility coefficient, σf0: scaling parameter; n = 10 at 10-2, 10-1, 101, 100 and 102 MPa/s). Strength-probability-time (SPT) diagrams were plotted by merging SCG and Weibull parameters.

    RESULTS: There was no significant difference in the m value of all materials. However, 0.5 GO presented the lowest σ0, whereas all other groups were similar. The lowest n value obtained for all GO-modified PMMA groups (27.4 for 0.05 GO) was higher than the Control (15.6). The strength degradation predicted after 15 years for Control was 12%, followed by 0.01 GO (7%), 0.05 GO (9%), 0.1 GO (5%), and 0.5 GO (1%).

    SIGNIFICANCE: The hypothesis was partially accepted as GO increased PMMA's fatigue resistance and lifetime but did not significantly improve its Weibull parameters. GO added to PMMA did not significantly affect the initial strength and reliability but significantly increased PMMA's predicted lifetime. All the GO-containing groups presented higher resistance to fracture at all times analyzed compared with the Control, with the best overall results observed for 0.1 GO.

    Matched MeSH terms: Ceramics
  13. Al-Maqtari AA, Razak AA, Hamdi M
    Dent Mater J, 2014;33(4):458-65.
    PMID: 25087658
    This study aimed at investigating and establishing stress distributions in graded multilayered zirconia/alumina ceramic cores and at veneer-core-cement-dentin interfaces, using finite element analysis (FEA), to facilitate the structural design of ceramic cores through computer modeling. An intact maxillary premolar was digitized using CT scanning. An imaging software, Mimics, was used to reconstruct 3D models based on computed tomography (CT) data saved in DICOM format. Eight different 3D models were created for FEA, where each 3D model was meshed and its bottom boundaries constrained. A static load was applied in the oblique direction. The materials were assumed to be isotropic and homogeneous. Highest von Mises stress values were found in areas directly below the load application point, and stress gradually decreased in occlusal loading direction from the external surface toward the dentin. Stress levels occurring at veneer-ceramic core-cement-dentin interfaces were shown to be lower in multilayered ceramic cores than in single-layer models.
    Matched MeSH terms: Ceramics*
  14. Tawalbeh M, Mohammed S, Al-Othman A, Yusuf M, Mofijur M, Kamyab H
    Environ Res, 2023 Jul 01;228:115919.
    PMID: 37072081 DOI: 10.1016/j.envres.2023.115919
    The rapid increase in the global population and its ever-rising standards of living are imposing a huge burden on global resources. Apart from the rising energy needs, the demand for freshwater is correspondingly increasing. A population of around 3.8 billion people will face water scarcity by 2030, as per the reports of the World Water Council. This may be due to global climate change and the deficiency in the treatment of wastewater. Conventional wastewater treatment technologies fail to completely remove several emerging contaminants, especially those containing pharmaceutical compounds. Hence, leading to an increase in the concentration of harmful chemicals in the human food chain and the proliferation of several diseases. MXenes are transition metal carbide/nitride ceramics that primarily structure the leading 2D material group. MXenes act as novel nanomaterials for wastewater treatment due to their high surface area, excellent adsorption properties, and unique physicochemical properties, such as high electrical conductivity and hydrophilicity. MXenes are highly hydrophilic and covered with active functional groups (i.e., hydroxyl, oxygen, fluorine, etc.), which makes them efficient adsorbents for a wide range of species and promising candidates for environmental remediation and water treatment. This work concludes that the scaling up process of MXene-based materials for water treatment is currently of high cost. The up-to-date applications are still limited because MXenes are currently produced mainly in the laboratory with limited yield. It is recommended to direct research efforts towards lower synthesis cost procedures coupled with the use of more environmentally friendly materials to avoid secondary contamination.
    Matched MeSH terms: Ceramics*
  15. Yusof MSM, Othman MHD, Mustafa A, Rahman MA, Jaafar J, Ismail AF
    Environ Sci Pollut Res Int, 2018 Aug;25(22):21644-21655.
    PMID: 29785602 DOI: 10.1007/s11356-018-2286-6
    Palm oil fuel ash (POFA) is an agricultural waste which was employed in this study to produce novel adsorptive ceramic hollow fibre membranes. The membranes were fabricated using phase inversion-based extrusion technique and sintered at 1150 °C. The membranes were then evaluated on their ability to adsorb cadmium (Cd(II)). These membranes were characterised using (nitrogen) N2 adsorption-desorption analysis, field emission scanning electron microscopy-energy-dispersive X-ray spectroscopy (FESEM-EDX) mapping, X-ray fluorescence (XRF), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) analyses while adsorptivity activity was examined by batch adsorption studies. The adsorption test results show that the quantity of hollow fibre used and water pH level significantly affected the adsorption performance with the 3-fibre membrane yielding 96.4% Cd(II) removal in 30 min equilibrium time at pH 7. These results are comparable to those reported by other studies, and hence demonstrate a promising alternative of low-cost hollow fibre adsorbent membrane. Graphical abstract Figure of FESEM image of the hollow fibre, proposed mechanism and the graph of percentage removal of Cd(II) using POFA.
    Matched MeSH terms: Ceramics
  16. Mohtor NH, Othman MHD, Ismail AF, Rahman MA, Jaafar J, Hashim NA
    Environ Sci Pollut Res Int, 2017 Jul;24(19):15905-15917.
    PMID: 28620856 DOI: 10.1007/s11356-017-9341-6
    Despite its extraordinary price, ceramic membrane can still be able to surpass polymeric membrane in the applications that require high temperature and pressure conditions, as well as harsh chemical environment. In order to alleviate the high cost of ceramic material that still becomes one of the major factors that contributes to the high production cost of ceramic membrane, various attempts have been made to use low cost ceramic materials as alternatives to well-known expensive ceramic materials such as alumina, silica, and zirconia in the fabrication of ceramic membrane. Thus, local Malaysian kaolin has been chosen as the ceramic material in this study for the preparation of kaolin hollow fibre membrane since it is inexpensive and naturally abundant in Malaysia. Due to the fact that the sintering process plays a prominent role in obtaining the desired morphology, properties, and performances of prepared ceramic membrane, the aim of this work was to study the effect of different sintering temperatures applied (ranging from 1200 to 1500 °C) in the preparation of kaolin hollow fibre membrane via dry/wet phase inversion-based spinning technique and sintering process. The morphology and properties of membrane were then characterised by SEM, AFM, FTIR, XRD, and three-point bending test, while the performances of membrane were investigated by conducting water permeation and Reactive Black 5 (RB5) dye rejection tests. From the experimental results obtained, the sintering temperature of 1400 °C could be selected as the optimum sintering temperature in preparing the kaolin hollow fibre membrane with the dense sponge-like structure of separation layer that resulted in the good mechanical strength of 70 MPa with the appreciable water permeation of 75 L/h m(2) bar and RB5 rejection of 68%.
    Matched MeSH terms: Ceramics
  17. Rajeev V, Arunachalam R, Nayar S, Arunima PR, Ganapathy S, Vedam V
    Eur J Dent, 2017 4 25;11(1):58-63.
    PMID: 28435367 DOI: 10.4103/ejd.ejd_113_16
    OBJECTIVE: This in vitro study was designed to assess shear bond strength (SBS) of ormocer flowable (OF) resin as a luting agent, ormocer as an indirect veneer material with portrayal of modes of failures using scanning electron microscope (SEM).

    MATERIALS AND METHODS: Sixty maxillary central incisors were divided into Group I, II, and III with 20 samples each based on luting cement used. They were OF, self-adhesive (SA) cement, and total etch (TE) cement. These groups were subdivided into "a" and "b" of ten each based on the type of veneering materials used. Veneer discs were fabricated using Ormocer restorative (O) and pressable ceramic (C). Specimens were thermocycled and loaded under universal testing machine for SBS. The statistical analysis was done using one-way ANOVA post hoc Tukey honest significant difference method.

    RESULTS: A significant difference was observed between the Groups I and II (P < 0.05). The highest mean bond strength when using ormocer veneer was obtained with the Group Ia (19.11 ± 1.92 Mpa) and lowest by Group IIa (8.1 ± 1.04 Mpa), whereas the highest mean bond strength while using ceramic veneer was of similar range for Group Ib (18.04 ± 4.08 Mpa) and Group IIIb (18.07 ± 1.40 Mpa). SEM analysis revealed OF and TE presented mixed type of failure when compared with SA where failure mode was totally adhesive.

    CONCLUSION: OF was found equally efficient like TE. Bond strength of ormocer as a veneer was not inferior to ceramic making it one of the promising additions in the field of dentistry.

    Matched MeSH terms: Ceramics; Organically Modified Ceramics
  18. Abdul Hamid NF, Wan Bakar WZ, Ariffin Z
    Eur J Dent, 2019 Feb;13(1):17-21.
    PMID: 31170751 DOI: 10.1055/s-0039-1688740
    OBJECTIVE: This study was carried out to assess and compare the marginal gap of conventionally used metal onlays and new resin nanoceramic (RNC) (Lava Ultimate block) onlays.

    MATERIALS AND METHODS: This is an in vitro study using two extracted sound human mandibular molars. One tooth was prepared to receive the metal onlays and another one for the RNC onlays which were fabricated using the computer-aided design and computer-aided manufacturing (CAD/CAM) technology. Twelve metals and 12 ceramic onlays were fabricated before they were placed at their respective preparation and examined under the Leica stereomicroscope, M125C (Leica Microsystems, Wetzlar, Germany) for a marginal analysis. The gap width was measured at 10 predefined landmarks which included 3 points on the buccal and lingual surfaces each and 2 points each on the mesial and distal surfaces, respectively.

    STATISTICAL ANALYSIS: Mann-Whitney post hoc test was used for statistical analysis (P ≤ 0.05).

    RESULTS: Overall, the RNC onlays showed significant lower marginal gap with the exception of the landmarks 5 and 6 (on distolingual) and no significant difference at landmark 7 (on midlingual). It was observed that the marginal gap were all within the clinically acceptable limit of 120 μm.

    CONCLUSIONS: Based on the results obtained, it can be concluded that the RNC CAD/CAM onlays are a promising alternative to the metal onlays.

    Matched MeSH terms: Ceramics
  19. Brandão A, Eng KK, Rito T, Cavadas B, Bulbeck D, Gandini F, et al.
    Hum Genet, 2016 Apr;135(4):363-76.
    PMID: 26875094 DOI: 10.1007/s00439-016-1640-3
    There has been a long-standing debate concerning the extent to which the spread of Neolithic ceramics and Malay-Polynesian languages in Island Southeast Asia (ISEA) were coupled to an agriculturally driven demic dispersal out of Taiwan 4000 years ago (4 ka). We previously addressed this question using founder analysis of mitochondrial DNA (mtDNA) control-region sequences to identify major lineage clusters most likely to have dispersed from Taiwan into ISEA, proposing that the dispersal had a relatively minor impact on the extant genetic structure of ISEA, and that the role of agriculture in the expansion of the Austronesian languages was therefore likely to have been correspondingly minor. Here we test these conclusions by sequencing whole mtDNAs from across Taiwan and ISEA, using their higher chronological precision to resolve the overall proportion that participated in the "out-of-Taiwan" mid-Holocene dispersal as opposed to earlier, postglacial expansions in the Early Holocene. We show that, in total, about 20 % of mtDNA lineages in the modern ISEA pool result from the "out-of-Taiwan" dispersal, with most of the remainder signifying earlier processes, mainly due to sea-level rises after the Last Glacial Maximum. Notably, we show that every one of these founder clusters previously entered Taiwan from China, 6-7 ka, where rice-farming originated, and remained distinct from the indigenous Taiwanese population until after the subsequent dispersal into ISEA.
    Matched MeSH terms: Ceramics
  20. Hutagalung SD, Ying OL, Ahmad ZA
    PMID: 18276560 DOI: 10.1109/TUFFC.2007.582
    This paper presents the effects of calcination time and sintering temperature on the properties of CaCu(3)Ti(4)O(12). Electroceramic material of CaCu(3)Ti(4)O(12) was prepared using a modified mechanical alloying technique that covers several processes, which are preparation of raw material, mixing and ball milling for 5 hours, calcination, pellet forming and, sintering. The objective of this modified technique is to enable the calcination and sintering processes to be carried out at a shorter time and lower temperature. The x-ray diffraction (XRD) analysis result shows that a single-phase of CaCu(3)Ti(4)O(12) was completely formed by calcination at 750 degrees C for 12 hours. Meanwhile, the grain size of a sample sintered at 1050 degrees C for 24 hours is extremely large, in the range of 20-50 mum obtained from field emission scanning electron microscopy (FESEM) images. The dielectric constant value of 14,635 was obtained at 10 kHz by impedance (LCR) meter in the sintered sample at 1050 degrees C. However, the dielectric constant value of samples sintered at 900 and 950 degrees C is quite low, in the range of 52-119.
    Matched MeSH terms: Ceramics/chemistry*
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