Displaying publications 21 - 40 of 114 in total

Abstract:
Sort:
  1. Siti Nazira Masrom, Mohd Hariri Arifin, Abd Rahim Harun, Abdul Rahim Samsudin
    Sains Malaysiana, 2011;40:1223-1229.
    Survei keberintangan geoelektrik ini telah dijalankan di kawasan Bukit Tenggek, Setiu, Terengganu untuk mengesan kemungkinan wujudnya terowong lama yang dipercayai berada di kawasan berkenaan. Kaedah keberintangan geoelektrik ini bukanlah asing dan didapati amat berkesan di dalam eksplorasi mencari bahan arkeologi dan struktur terkambus di bawah tanah (terowong dan bahan artifak). Survei keberintangan geoelektrik ini dijalankan dengan menggunakan peralatan ABEM Terrameter SAS1000 dan susun atur elektrod jenis Wenner. Kawasan kajian terletak di kawasan lembah yang lembap dan terdapat anak sungai yang merentasi kawasan tersebut. Imej keberintangan 2-D menunjukkan wujudnya beberapa kawasan beranomali yang boleh dikaitkan dengan struktur yang dicari. Nilai keberintangan yang rendah mewakili kawasan yang dianggarkan wujudnya terowong lama. Manakala anomali yang menunjukkan bentuk gugusan dianggarkan berasosiasi dengan lokasi tong/bahan artifak. Profil keberintangan 3-D menunjukkan anomali yang mungkin disebabkan oleh wujudnya satu terowong mendatar dan dua terowong menegak. Namun, kerja galicari perlu dilakukan bagi menentukan punca sebenar anomali tersebut.
    Matched MeSH terms: Composite Resins
  2. 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: Composite Resins
  3. Sidhu P, Sultan OS, Math SY, Malik NA, Wilson NHF, Lynch CD, et al.
    J Dent, 2021 07;110:103683.
    PMID: 33957189 DOI: 10.1016/j.jdent.2021.103683
    OBJECTIVE: To investigate the current and future teaching of posterior composite restorations in undergraduate curricula in Malaysian dental schools.

    METHODS: A 24-item validated questionnaire including closed and open questions on the teaching of posterior composites was emailed to faculty members in all 13 Dental Schools in Malaysia. Responses were compiled on Excel and analysed.

    RESULTS: All 13 dental schools responded to the survey yielding a 100 % response. All schools indicated the use of posterior composites for 2- and 3-surface cavities in premolars and molars. The didactic teaching time devoted to composites was greater than for amalgam (38 h vs 29 h). Clinically, most posterior restorations placed by students were composites (average 74.1 %, range 10 %-100 %); the remaining 25.9 % were amalgams (range, 0 %-50 %). Slot-type cavities were the preparation techniques most commonly taught (n = 11,84.6 %). The use of rubber dam for moisture control was mandatory in most schools (n = 11, 84.6 %). History of adverse reaction to composites was found to be the most common contraindication to composite placement. The phase down of teaching and use of amalgam in Malaysia is expected to occur within the next six years.

    CONCLUSION: The trend to increase the teaching of posterior composites reported for other countries is confirmed by the findings from Malaysian dental schools. Notwithstanding this trend, the use of amalgam is still taught, and future studies are required to investigate the implications of the phase down of amalgam in favour of posterior composites.

    CLINICAL SIGNIFICANCE: Notwithstanding the increase in the teaching of posterior composites there is a pressing need to update and refine clinical guidelines for the teaching of posterior composites globally.

    Matched MeSH terms: Composite Resins
  4. Shahidan Radiman
    The evolution of microemulsion microstructure formed from didodecyl dimethyl ammonium bromide, water and cyclohexane which started from being structureless (fiat scattering profile) to a mean-field Ginsburg-Landau behaviour is shown. The evolution gave the characteristic Lorentzian scattering profile as the system approaches phase separation.
    Evolusi mikrostruktur mikroemulsi yang terbentuk daripada didodesil dimetil ammonium bromida, air dan sildoheksana tiada berstruktur (profil serakan yang malar) kepada medan-min Ginsburg-Landau. Evolusi tersebut memberikan serakan Lorentz apabila komposisinya menghampiri sempadan pemisahan fasa.
    Matched MeSH terms: Composite Resins
  5. Seow, L.L., Chong, S.Y., Lau, M.N., Tiong, S.G., Yew, C.C.
    Malaysian Dental Journal, 2008;29(1):34-39.
    MyJurnal
    Certain beverages e.g. coffee, tea, soft drinks, fruit juices, alcoholic beverages, may affect the physical properties of composite resins. Objectives: The objectives of this study were to: (1) evaluate the effect of different beverages and chilli sauce on the wear resistance of composite resins, (2) evaluate effect of the duration of immersion in the beverages and chilli sauce on the wear resistance of composite resins.

    Materials and methods: Disc specimens were fabricated using two different types of composite resins: (i) Filtek Z350 (3M ESPE, USA, nano-filled composite, 40 specimens) and (ii) Solare P (GC Dental Products Corp, Japan, microhybrid composite, 40 specimens). After polymerization, all the specimens were polished using Enhance Polishing System (Dentsply International Inc.,USA). The specimens were air-dried before weighing using Sartorius BP 221S weighing balance (Sartorius AG, Goettingen, Germany). Ten specimens from each type of composite were immersed in distilled water (control group), Coca cola®, orange juice (Peel Fresh®) and chilli sauce (Maggi®) respectively. The duration of immersion was 6 hours and 1 week. A reciprocal compression-sliding system was used to evaluate the wear resistance of the specimens. The specimens were moved back and forth with a loaded counter-body (235g) against sand paper (P1000, 3M ESPE, USA) in running water. The weight of the specimens were measured after 6 hours of immersion and 20,000 wear cycles and also at 1 week of immersion with further 20,000 wear cycles. The wear resistances were tabulated as percentage of weight loss from the specimens. Results were statistically analyzed using one way ANOVA and post-hoc Tukey’s test (p= 0.05).
    Results: The results showed that Solare P has significantly lower wear resistance compared to Filtek Z350. There was no significant difference in wear resistance for Filtek Z350 when immersed in chili sauce, Coca-cola® and orange juice in comparison with control group for 6 hours and 1 week. Similar findings were observed for Solare P.

    Conclusion: Within the limitations of this study, it was concluded that Solare P has poorer wear resistance than Filtek Z350. The soaking medium investigated and duration of immersion have no influence on the wear resistance of Solare P and Filtek Z350.
    Matched MeSH terms: Composite Resins
  6. Samsuzzaman M, Islam MT, Mandeep JS, Misran N
    ScientificWorldJournal, 2014;2014:804068.
    PMID: 24696661 DOI: 10.1155/2014/804068
    This paper presents a printed wide-slot antenna design and prototyping on available low-cost polymer resin composite material fed by a microstrip line with a rotated square slot for bandwidth enhancement and defected ground structure for gain enhancement. An I-shaped microstrip line is used to excite the square slot. The rotated square slot is embedded in the middle of the ground plane, and its diagonal points are implanted in the middle of the strip line and ground plane. To increase the gain, four L-shaped slots are etched in the ground plane. The measured results show that the proposed structure retains a wide impedance bandwidth of 88.07%, which is 20% better than the reference antenna. The average gain is also increased, which is about 4.17 dBi with a stable radiation pattern in the entire operating band. Moreover, radiation efficiency, input impedance, current distribution, axial ratio, and parametric studies of S11 for different design parameters are also investigated using the finite element method-based simulation software HFSS.
    Matched MeSH terms: Composite Resins/economics; Composite Resins/chemistry*
  7. Salim NA, Muttlib NAA, Alawi R, Rahman NA, Ariffin Z
    Acta Stomatol Croat, 2018 Sep;52(3):218-226.
    PMID: 30510297 DOI: 10.15644/asc52/3/5
    Objective: This study aimed to compare the difference in marginal dye penetration between everStick, Parapost XP, Parapost fiber white and control groups under gradual loading.

    Materials and Methods: Sixty-eight human maxillary permanent incisors were divided into four groups. Each specimen was endodontically treated with step-back technique and prepared for each post system according to experimental groups, subsequently cemented in the canal. Composite resin cores were built and laboratory fabricated metal crowns were cemented. All specimens except those in the control group were subjected to thermal cycling. All groups were subjected to gradual loading from 0N-50N for 100 cycles. Specimens were sectioned transversely and the depths of dye penetration along the post were measured. Data were entered in SPSS ver. 22 and analyzed using two-way ANOVA test.

    Results: There was no significant difference in marginal dye penetration between each group (p-value>0.05). However, there was a significant difference in percentage of marginal dye penetration between all groups (p-value<0.05); post-hoc comparison showed significant difference between Fiber White and Control groups (p-value=0.009).

    Conclusion: All the groups showed dye penetration but the percentage was significant only between Parapost Fiber White and the control groups.

    Matched MeSH terms: Composite Resins
  8. Rizal S, Fizree HM, Hossain MS, Ikramullah, Gopakumar DA, Wan Ni EC, et al.
    Heliyon, 2020 Mar;6(3):e03550.
    PMID: 32190763 DOI: 10.1016/j.heliyon.2020.e03550
    This study was conducted to determine the influence of the oil palm boiler ash (OPBA) reinforcement on the microstructural, physical, mechanical and thermal properties of epoxy polymer composites. The chemical composition analysis of OPBA revealed that it contains about 55 wt.% of SiO2 along with other metallic oxides and elements. The surface morphology of OPBA showed angular and irregular shapes with porous structures. The influence of OPBA as a reinforcement in epoxy composite was studied with varying filler loadings (10-50 wt.%) and different particle sizes (50-150 μm). The result showed that the incorporation of OPBA in composites has improved the physical, mechanical and thermal properties of the epoxy matrix. The highest physical and mechanical properties of fabricated composites were attained with 30 wt.% loading and size of 50 μm. Also, thermal stability and the percentage of char residue of the composite increased with increasing filler loading. Furthermore, the contact angle of OPBA reinforced epoxy composites increased with the increase of filler loading. The lowest value of the contact angle was obtained at 30 wt.% of filler loading with the OPBA particle size of 50 μm. The finding of this study reveals that the OPBA has the potential to be used as reinforcement or filler as well as an alternative of silica-based inorganic fillers used in the enhancement of mechanical, physical and thermal properties of the epoxy polymer composite.
    Matched MeSH terms: Composite Resins
  9. 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: Composite Resins/analysis; Composite Resins/chemistry*
  10. Rahim TN, Mohamad D, Md Akil H, Ab Rahman I
    Dent Mater, 2012 Jun;28(6):e63-70.
    PMID: 22480722 DOI: 10.1016/j.dental.2012.03.011
    To determine the diffusion coefficient, water sorption and solubility of various types of restorative dental composites and to evaluate the effect of acidic media (orange juice and coke) on their characteristics.
    Matched MeSH terms: Composite Resins/chemistry*
  11. Radzi, Z., Yahya, N.A., Zamzam, N., Wood, D.J.
    Ann Dent, 2004;11(1):-.
    MyJurnal
    Choosing the right light-curing unit can be a very difficult task for some orthodontists. Currently, there are various types of light curing units available in the market with various trade names and specifications. Most of the time information regarding light curing units is obtained from advertisements, websites or manufacturers’ catalogues. Sometimes such information can be misleading. This article attempts to provide several tips for orthodontists in selecting light curing units.
    Matched MeSH terms: Composite Resins
  12. Radzi, Z., Abu Kasim, N.H., Yahya, N.A., Abu Osman, N.A., Kassim, N.L.
    Ann Dent, 2008;15(1):33-39.
    MyJurnal
    The purpose of this study was to investigate the light intensity of selected light curing units with varying distance and angulation of the light curing tip and lightmeter. Materials and method: Four types of light units; Spectrum 800 (Dentsply), Coltulux 3 (Coltene), Elipar FreeLight 2 (3M Espe) and Starlight Pro (Mectron) were evaluated for light intensity at various distances between the light curing tip and the radiometer Cure Rite Denstply (0,1,3,5,10 and 15 mm). The light curing units were tested at right angles to the aperture of the light meter and at the angles of 45°, 60° to it at a standardized 5 mm distance. Results: The highest light intensity was obtained when the tip of light curing unit was in contact with the lightmeter aperture. The light intensity decreased significantly when the light tip was placed 5mm, 10mm and 15mm away from the lightmeter aperture. However, no significant differences (p> .05) were detected between Omm, Imm and 3mm. There was a decrease in light intensity when light~·tip was angulated at 45° and 60° except for Coltolux 3. Conclusions: The intensity of the curing light was affected by the distance between the light curing tip and the lightmeter. However, the decrease in light intensity of the light curing unit was found not to obey the inverse square law for the distances 0 to 15 mm. The study found that there was no significant difference between 45° and 60° angulation between the light curing tip and the lightmeter. However, the decrease in light intensity was significant when compared to the light tip placed perpendicular (90°) to the aperture of the light meter.
    Matched MeSH terms: Composite Resins
  13. Qamar Z, Zeeshan T, Alqahtani WMS, Alanazi A, Khalid Aqeel Almejlad N, Ahmed Khan T, et al.
    Photodiagnosis Photodyn Ther, 2023 Sep;43:103689.
    PMID: 37414110 DOI: 10.1016/j.pdpdt.2023.103689
    AIM: The chief aim of the study was to determine/equate the surface roughness (SRa) and shear bond strength (BS) of pretreated PEEK discs with contemporary air abrasion techniques, photodynamic (PD) therapy by curcumin photosensitizer (PS) and conventional diamond grit straight fissure bur adhered to the composite resin discs.

    MATERIAL AND METHOD: Two hundred discs of PEEK were prepared of 6 mm × 2 mm × 10 mm dimension. The discs were randomly divided into five groups (n = 40) for treatment, Group I: treatment with deionized distilled water (control group); Group II: PD therapy using curcumin PS; Group III: discs treated and abraded with air-borne particles (ABP) silica (30 μm particle size) modified alumina (Al); Group IV: ABP of alumina (110 μm particle size); and Group V: The PEEK were finished with 600-μm grit size straight diamond cutting bur installed in high speed hand-piece. The surface profilometer was used to evaluate the values of surface roughness (SRa) of pretreated PEEK discs. The discs were luted and bonded to discs of composite resin. The bonded PEEK samples were placed in Universal testing machine to evaluate shear BS. The type of BS failure for PEEK discs pre-treated with five regimes respectively was evaluated under stereo-microscope. The data was statistically analyzed using one-way ANOVA and the comparisons between mean values of shear BS were evaluated by Tukey's test (ρ≤0.05).

    RESULTS: The PEEK samples pre-treated with diamond cutting straight fissure burs displayed statistically significant highest value of SRa values (3.258± 0.785 µm). Similarly, the shear BS was observed to be higher for the PEEK discs pre-treated with straight fissure bur (22.37±0.78 MPa). A comparable difference but not statistically significant difference was observed between PEEK discs pre-treated by curcumin PS and ABP-silica modified alumina (ρ ≥ 0.05).

    CONCLUSION: PEEK discs pre-treated with diamond grit straight fissure bur displayed highest values of SRa and shear BS. It was trailed by ABP-Al pre-treated discs; whereas the SRa and shear BS values for the discs pre-treated with ABP-silica modified Al and curcumin PS did not show competitive difference.

    Matched MeSH terms: Composite Resins/chemistry
  14. 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: Composite Resins*
  15. Purmal K, Sukumaran P
    Aust Orthod J, 2010 Nov;26(2):184-8.
    PMID: 21175030
    To investigate the shear bond strengths of buccal tubes and to determine the sites of failure.
    Matched MeSH terms: Composite Resins/chemistry
  16. Purmal K, Nambiar P
    J Vet Dent, 2009;26(1):36-9.
    PMID: 19476086
    Matched MeSH terms: Composite Resins
  17. Nurul Shazana Abdul Hamid, Viksuthorn Ai Wen, Nur Izzati Mohd Rosli, Akimasa Yoshikawa, Akimasa Yoshikawa
    Sains Malaysiana, 2018;47:1923-1929.
    Sistem arus di ionosfera khatulistiwa terdiri daripada elektrojet khatulistiwa (EEJ) dan suria senyap (Sq). Arus EEJ merupakan satu jalur arus yang mengalir ke arah timur sepanjang kawasan dip khatulistiwa. Arus Sq pula adalah gegelung arus yang mengalir di hemisfera utara dan selatan bumi pada arah yang bertentangan. Kajian ini bertujuan untuk menganalisis kesan aktiviti matahari terhadap profil latitud sistem arus, khususnya di kawasan Asia Tenggara. Data yang digunakan dalam kajian ini merangkumi data geomagnet daripada lima stesen magnetometer dalam rangkaian MAGDAS iaitu stesen Muntinlupa (MUT), Cebu (CEB), Davao (DAV), Manado (MND) dan Pare Pare (PRP). Keamatan arus EEJ yang paling tinggi adalah pada waktu tengah hari sekitar 1000 dan 1100 LT semasa solar minimum dan kajian ini telah menganalisis sistem arus daripada 1000 hingga 1400 LT. Analisis menunjukkan bahawa ribut geomagnet yang berlaku pada 23 April 2008 adalah disebabkan oleh letusan jirim korona (CME) yang memberikan peningkatan kepada nilai arus pada hari tersebut. Peningkatan yang ketara dapat dilihat pada arus di stesen hemisfera selatan, iaitu stesen MND dan PRP. Berdasarkan analisis yang dilakukan, ia turut mendapati bahawa ribut geomagnet memberikan peningkatan kepada nilai arus walaupun di luar waktu puncak. Selain itu, profil arus ini turut dibandingkan dengan profil arus pada hari senyap iaitu pada 21 April 2008.
    Matched MeSH terms: Composite Resins
  18. Norul Azlin, M.Z., Senin, H.B., Kok Sheng, C.
    MyJurnal
    Phenolic resin-silica nanocomposites samples in pellet shape have been successfully prepared by intercalation of polymer solution through the hot pressing method. The phenolic resin is modified with organic elastomers of silica nanoparticles, which is about 20 nanometer in diameter. The change of density and porosity was studied based on the addition of silica content in the phenolic resin composites. The densities of composites increased with the addition of the silica content from 10 wt.% to 40 wt.%. On the other hand, the porosity percentage was decreased with increasing of silica contents. The mechanical properties (Young’s modulus, energy to break and time to failure) of the nanocomposites samples were identified using the Universal Testing Material Machine (UTM). The results of Young’s modulus, energy to break and time to failure of the phenolic resin composites were found to be slightly increased with silica content from 10 wt.% to 30 wt.%. The X-Ray Microtomogaphy (XRM) topographies have shown that the porosity exists on fracture structure for each nanocomposite. The nanocomposites surface structure has been analyzed using Scanning Electron Microscope (SEM). The observation shows that the fracture surface of the pure phenolic resin is relatively smooth and glassy, which is typical for a brittle material, but the phenolic resin- silica composites fracture surface is not smooth at all. The observations indicate the pure phenolic resin is brittle than phenolic resin-silica nanocomposites. Consequently, the physical properties of the phenolic resin-silica nanocomposites were improved with the addition of 10 wt.% to 30 wt.% silica contents, as compared to that of the pure phenolic resin.
    Matched MeSH terms: Composite Resins
  19. Normaliza Ab. Malik, Marhazlinda Jamaludin, Seow, Liang Lin
    Malaysian Dental Journal, 2010;31(1):52-57.
    MyJurnal
    Objectives: To evaluate the marginal microleakage of Class II cavities restored with various types of composite resins.
    Materials and Methods: Standard Class II slot cavities were prepared at the proximal surfaces of 40 intact premolars which were divided into 4 groups. Four types of composite resins (Esthet-X-Denstply, USA, FiltekTMZ350- 3M ESPE, USA, Beautifil- Shofu, Japan and Solare P-GC, Japan) were used to restore the slot cavities. All the specimens were thermocycled and immersed in 0.5% basic fuschin dye for 24 hours. The specimens were then sectioned in mesio-distal direction. The marginal microleakage at the occlusal and cervical margin was scored using the ISO microleakage scoring system. Data was entered using SPSS Version 12.0 and analyzed using STATA software programme.
    Results and discussion: All composite resins exhibited worse microleakage at the cervical margin compared to occlusal margin. Esthet-X showed significantly better microleakage score at the occlusal margin compared to Beautifil and Solare P. FiltekTMZ350 and Beautifil showed mainly microleakage into enamel only at the occlusal margin. Solare P demostrated better resistance against microleakage at the cervical margin compared to other composite resin tested. Esthet-X, Filtek Z350 and Beautiful is not significantly different from each other in terms of microleakage at the cervical margin.
    Conclusion: This study showed that none of the materials used in this study is able to eliminate microleakage. Composite resin restorations exhibited worse micorleakage at cervical margin in comparison to occlusal margin.
    Matched MeSH terms: Composite Resins
  20. Normaliza Ab. Malik, Seow LL, Normastura Abd. Rahman, Marhazlinda Jamaludin
    Sains Malaysiana, 2013;42:45-51.
    This study was carried out to evaluate the microleakage of Class II cavities restored with various types of lining materials. Four types of composite resins (Esthet-X-Denstply, USA, FiltekTMZ350-3M ESPE, USA, Beautifil- Shofu, Japan and Solare P-GC, Japan) were used and the lining were the Fuji IXGP (GC, Japan), the Beautifil flow (Shofu, Japan), the FiltexTMZ350 flow (3M ESPE, USA) and the Esthet-X flow (Denstply, USA). All the specimens were thermocycled and immersed in 0.5% basic fuschin dye for 24 h. The microleakage was scored using the ISO microleakage scoring system. The data were entered using SPSS version 12.0 and analyzed using STATA software programme. This study showed that none of the materials used in this study was able to eliminate microleakage. However, it was shown that the glass ionomer cement was better in reducing the incident of microleakage at the cervical margin. Among the flowable composite resin, FiltexTMZ350 flow showed less microleakage at the cervical margin.
    Matched MeSH terms: Composite Resins
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links