Ping Wang

Wuhan University of Technology, Wu-han-shih, Hubei, China

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Publications (27)47.6 Total impact

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    ABSTRACT: Usually, cocatalyst modification of photocatalysts is an efficient approach to enhance the photocatalytic performance by promoting effective separation of photogenerated electrons and holes. It is highly required to explore new and effective cocatalysts to further enhance the photocatalytic performance of photocatalytic materials. In the present work, Cu(II) cocatalyst was successfully loaded on the surface of various Ag-based compounds (such as AgCl, Ag3PO4, AgBr, AgI, Ag2CO3, and Ag2O) by a simple impregnation route, and their photocatalytic activity of Cu(II)/Ag-based photocatalysts was evaluated by the photocatalytic decolorization of methyl orange and photocatalytic decomposition of phenol solution under visible-light illumination. As one of the typical photosensitive Ag-based compounds, the photocatalytic activity of AgCl could be greatly improved by optimizing the amount of Cu(II) cocatalyst, and the highest photocatalytic performance of the resulted Cu(II)/AgCl was higher than that of the unmodified AgCl by a factor of 2.1. Significantly, the Cu(II) was demonstrated to be a general and effective cocatalyst to improve the visible-light photocatalytic performance of other various photosensitive Ag-based compounds (such as AgBr, AgI, Ag3PO4, Ag2CO3, and Ag2O) in addition to the AgCl photocatalyst. Based on the present results, it is proposed that the Cu(II) cocatalyst functions as electron scavengers to quickly capture photogenerated electrons from the excited photocatalysts and then works as reduction active sites to reduce O2 effectively, resulting in an effective separation of photogenerated electrons and holes. Compared with the expensive noble metal cocatalyst (such as Pt, Au, and Pd), the present promising Cu(II) cocatalyst can be considered to be one of the perfect cocatalysts for the smart preparation of various highly efficient photocatalysts in view of its abundance and low cost.
    The Journal of Physical Chemistry C. 04/2014; 118(17):8891–8898.
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    ABSTRACT: Usually, cocatalyst modification and nanonization of photocatalytic materials have been demonstrated to be two kinds of effective strategies to improve the photocatalytic performance. For the well-known Ag/AgCl photocatalyst, it is difficult to obtain AgCl nanoparticles by a conventional precipitation reaction in aqueous solutions. It is highly required to develop a facile and effective strategy to simultaneously realize the cocatalyst modification and nanonization of Ag/AgCl photocatalysts. In this study, cocatalyst modification and nanonization of Ag/AgCl photocatalyst were simultaneously realized via a facile reduction–reoxidization route by using graphene oxide (GO) as the cocatalyst modifier. It was found that the chemical reduction of both Ag+ and GO by NaBH4 leaded to the formation of nanoscale Ag grafted on the reduced GO (rGO), whereas the following in situ reoxidization of metallic Ag in FeCl3 solution resulted in the final formation of well-dispersed Ag/AgCl nanoparticles on the rGO surface. Owing to a good encapsulation of Ag nanoparticles by rGO nanosheets, the resultant AgCl nanoparticles could be easily controlled to be 20–200 nm and were tightly grafted on the rGO cocatalyst surface. The photocatalytic experimental results indicated that all the Ag/AgCl-rGO (1–5 wt% rGO) nanocomposites exhibited a much higher photocatalytic decomposition of phenol than the Ag/AgCl under visible light irradiation, and the Ag/AgCl-rGO (3 wt% rGO) showed the highest performance. The enhanced photocatalytic activity of Ag/AgCl-rGO can be attributed to the cooperation effect of rGO nanosheet cocatalyst promoting the effective transfer of photogenerated electrons, and the nanonization of AgCl particles that provide more surface active sites for the decomposition of organic substances. This work may provide new insights into the fabrication of high-performance visible-light photocatalytic materials.
    Journal of Molecular Catalysis A Chemical 01/2014; 381:114–119. · 3.19 Impact Factor
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    ABSTRACT: Narrow band-gap (NBG) Ag2S nanocrystals (NCs) attaching on the surface of wide band-gap (WBG) Ag8W4O16 nanorods were prepared by employing a facile in situ anion exchange method with the reaction between S(2)(-) and WO4(2-), and the photocatalytic activity was evaluated by the photocatalytic decolorization of methyl orange solution under visible-light irradiation. It was found that in situ anion exchange could uniformly deposit Ag2S NCs on the surface of Ag8W4O16 nanorods, controllably adjust the size, distribution and amount of Ag2S NCs, and solidly connect Ag2S NCs to the Ag8W4O16 nanorods via the replacement of S(2)(-) in the solution with lattice WO4(2-) on the Ag8W4O16 surface. The photocatalytic results indicated that the as-prepared Ag2S/Ag8W4O16 composite photocatalysts exhibited obviously higher activity compared with the pure Ag8W4O16 and N-TiO2 photocatalysts. On the basis of band structures of Ag2S and Ag8W4O16 semiconductors and the quantum size effect of Ag2S NCs, a possible photocatalytic mechanism about the Ag2S nanocrystal-sensitized Ag8W4O16 nanorods was proposed to account for the effective visible-light photocatalytic activities. This present work may provide some insight into the design of novel and high-efficiency NBG semiconductor NCs coupled with WBG semiconductor composite photocatalysts.
    Journal of Colloid and Interface Science 01/2014; 422:30–37. · 3.55 Impact Factor
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    ABSTRACT: The TiO2 film electrodes sensitized with CdS quantum dots (QDs) via chemical bath deposition method were successfully prepared as the photoanode of dye-sensitized solar cells (DSSCs). Microstructural characterizations by XRD, SEM, TEM and EDX show that the CdS nanocrystals with the cubic structure have intimate contact to the TiO2 films. The amount of CdS QDs can be controlled by varying the dipping time. The experiment results demonstrate that the CdS QDs-sensitized solar cells show a wider absorption in the solar spectrum and an enhanced surface photovoltage response. The maximal photoelectric conversion efficiency of 5.57% was achieved by the DSSC based on CdS QDs-sensitized TiO2 film with 4 min. The performance improvement is ascribed to the enhancement of electron transport, the reduction of electron recombination and the long electron lifetime.
    Materials Research Bulletin. 07/2013; 48(7):2566–2570.
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    ABSTRACT: Metastable materials have received extensive attention due to their unique physical and chemical properties which are different from those of the thermodynamically stable phase. However, the variety of reported metastable materials is still very limited owing to difficulties in the effective synthesis of pure metastable materials because they can easily transform into the corresponding stable phases. Therefore, it is crucial and a great challenge to explore new metastable materials with novel and fascinating functions. In this study, hierarchically porous metastable β-Ag2WO4 hollow nanospheres with a diameter of 50-500 nm were prepared for the first time by a facile precipitation reaction between AgNO3 and Na2WO4 in the presence of poly(methacrylic acid) (PMAA). It was found that the PMAA not only provided a spherical soft template to induce the formation of hollow nanospheres but also worked as an inhibitor to prevent the phase transformation from thermodynamically unstable β-Ag2WO4 to stable α-Ag2WO4 phase. The resultant metastable β-Ag2WO4 hollow nanospheres show a larger specific surface area (165.5 m(2) g(-1)) owing to the hierarchically porous structure (micropores, mesopores, and macropores), resulting in a high photocatalytic performance for the decomposition of methyl orange and phenol aqueous solutions. The present work can provide some new insight into the smart design and preparation of other new metastable hollow materials, and the prepared metastable β-Ag2WO4 hollow nanospheres have various potential applications in chemical reactors, drug-delivery carriers, solar cells, catalysis, and separation and purification fields.
    Nanotechnology 04/2013; 24(16):165602. · 3.84 Impact Factor
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    ABSTRACT: Dental pulp inflammation has long been perceived as a negative factor leading to pulp disruption. Previous studies have suggested that the inflammatory reaction might be a prerequisite for the burst of progenitors implicated in pulp repair. To investigate the migration of human dental pulp stem cells (hDPSCs) in response to human dental pulp fibroblasts (HDPFs) nemosis, an in vitro model of nemosis-induced inflammation in three-dimensional culture was used in this study. We observed HDPF spheroid formation and that cell-cell adhesion between HDPFs leads to necrosis. Cell death detection and cell counting kit-8 assays showed reduced live cell numbers and increased levels of cell membrane leakage in HDPF spheroids. HDPFs spheroids expressed cyclooxygenase-2 and released an increasing amount of prostaglandin E2 and interleukin-8, indicating inflammation in response to nemosis. The Transwell assays showed that the conditioned medium from HDPFs spheroids significantly induced hDPSCs migration more than the medium from the monolayer. Taken together, these results indicate that HDPFs spheroids induce nemosis and contribute to the migration of hDPSCs. This model might provide a potential research tool for studying interactions between fibroblasts and stem cells, and studies concerning nemosis-targeted stem cells might help treat pulp inflammation.
    Experimental Cell Research 04/2013; · 3.56 Impact Factor
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    ABSTRACT: The reduction of graphene oxide (GO) with a large-scale production has been demonstrated to be one of the key steps for the preparation of graphene-based composite materials with various potential applications. Therefore, it is highly required to develop facile, green and environmental-friendly route for the effective reduction of GO. In this study, a new and effective reduced method of GO nanosheets, based on the dye-sensitization-induced visible-light reduction mechanism, was developed to prepare reduced GO (rGO) and graphene-based TiO2 composite in the absence of any additional reducing agents. It was found that the dye-sensitization-induced reduction process of GO was accompanied with the formation of TiO2-rGO composite nanostructure. The photocatalytic experimental results indicated that the resultant TiO2-rGO nanocomposites exhibited significantly higher photocatalytic performance than pure TiO2 due to a rapid separation of photogenerated electrons and holes by the rGO cocatalyst.
    ACS Applied Materials & Interfaces 03/2013; · 5.01 Impact Factor
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    ABSTRACT: The mandibular first molars mostly have two mesial canals. In this report, two cases of mandibular first molars with three mesial canals are presented. The middle mesial canal was detected under endodontic microscope and further confirmed by cone-beam computed tomography and angled radiography, respectively. The purpose of this paper was to highlight the possibility of an aberrant root canal in a mandibular first molar and to help reduce the failure rates of the dental pulp treatment of the mandibular first molar.
    The Chinese journal of dental research: the official journal of the Scientific Section of the Chinese Stomatological Association (CSA) 01/2013; 16(1):75-8.
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    ABSTRACT: Ag modification has been demonstrated to be an efficient strategy to improve the photocatalytic performance of TiO2 photocatalysts. However, the previous studies about the Ag modification are only restricted to the surface loading of metallic Ag or Ag(I) doping, investigations have seldom been focused on the simultaneously deposited and doped Ag/Ag(I)-TiO2 photocatalyst. In this study, Ag/Ag(I)-TiO2 photocatalyst was prepared by a facile impregnated method in combination with a calcination process (450 °C) and the photocatalytic activity was evaluated by the photocatalytic decomposition of methyl orange and phenol solutions under both UV- and visible-light irradiation, respectively. It was found that Ag(I) doping resulted in the formation of an isolated energy level of Ag 4d in the band gap of TiO2. On the basis of band-structure analysis of Ag/Ag(I)-TiO2 photocatalyst, a possible photocatalytic mechanism was proposed to account for the different UV- and visible-light photocatalytic activities. Under visible-light irradiation, the isolated energy level of Ag 4d contributes to the visible-light absorption while the surface metallic Ag promotes the effective separation of the following photogenerated electrons and holes in the Ag/Ag(I)-TiO2 nanoparticles, resulting in a higher visible-light photocatalytic activity than the one-component Ag-modified TiO2 (such as Ag(I)-TiO2 and Ag/TiO2). Under UV-light irradiation, the doping energy level of Ag(I) ions in the band gap of TiO2 acts as the recombination center of photogenerated electrons and holes, leading to a lower photocatalytic performance of Ag-doped TiO2 (such as Ag/Ag(I)-TiO2 and Ag(I)-TiO2) than the corresponding undoped photocatalysts (such as Ag/TiO2 and TiO2). Considering the well controllable preparation of various Ag-modified TiO2 (such as TiO2, Ag/TiO2, Ag(I)-TiO2, and Ag/Ag(I)-TiO2), this work may provide some insight into the smart design of novel and high-efficiency photocatalytic materials.
    The Journal of Physical Chemistry C. 08/2012; 116(33):17721–17728.
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    ABSTRACT: AgI is instable under light irradiation owing to its photosensitive properties, while a supported Ag-AgI composite has been demonstrated to be a stable photocatalyst. However, seldom investigations have been focused on the photocatalytic activity (including deactivation) and photoinduced stability of the photosensitive AgI materials. In this study, the AgI nanoparticles were immobilized on the surface of Ag(8)W(4)O(16) nanorods by an anion-exchange route and their photocatalytic activities were evaluated by photocatalytic decomposition of methyl orange and phenol solutions under visible-light irradiation. A photoinduced self-stabilizing mechanism of the AgI nanoparticles was proposed to account for the formation of a stable Ag-AgI photocatalyst, namely, instable AgI can transform into a stable Ag-AgI photocatalyst after in situ formation of partial Ag on the surface of AgI nanoparticles. The photocatalytic performance of the immobilized AgI photocatalyst was greatly influenced by the formation of metallic Ag. With increasing repetitions of photocatalytic experiments, the initial deactivation was accompanied by the rapid increase of metallic Ag owing to the reduction of lattice Ag(+), while the subsequently stable activity corresponds to the formation of a stable Ag-AgI composite photocatalyst. Compared with the un-immobilized AgI photocatalyst, the immobilized AgI nanoparticles exhibited a higher and more stable photocatalytic performance.
    Dalton Transactions 07/2012; 41(34):10405-11. · 3.81 Impact Factor
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    ABSTRACT: Odontoblasts are involved in innate immunity against invading microorganisms. However, the mechanisms of host inflammatory responses to bacterial DNA in odontoblasts are not fully understood. The purpose of this study was to investigate whether microbial cytidine-phosphate-guanosine (CpG) DNA influences interleukin-8 (IL-8) expression in odontoblasts and the signaling pathways involved. The effect of CpG oligonucleotide (CpG ODN) on IL-8 mRNA and protein expression levels in the mouse odontoblast-like cell line MDPC-23 was investigated by real-time polymerase chain reaction (PCR) analysis and enzyme-linked immunosorbent assay (ELISA). Whether Toll-like receptor 9 (TLR9), myeloid differentiation marker 88 (MyD88), nuclear factor kappa B (NF-κB), or mitogen-activated protein kinase (MAPK) pathways were involved in the CpG ODN-induced IL-8 expression was determined by examined real-time PCR, ELISA, and luciferase activity assay. Extracellular signal-regulated kinase (ERK) activation and TLR9 protein expression were measured by Western blot analysis. Exposure to CpG ODN induced significant up-regulation of IL-8 mRNA and protein in MDPC-23 cells. CpG ODN-induced IL-8 up-regulation was attenuated by TLR9 inhibitor (chloroquine) and MyD88 inhibitory peptide. CpG ODN also increased the expression of TLR9 mRNA and protein in MDPC-23 cells. Treatment of MDPC-23 cells with NF-κB inhibitors (pyrrolidine dithiocarbamate), IκBα phosphorylation inhibitors (Bay 117082), or IκB protease inhibitor (L-1-tosylamido-2-phenylethyl chloromethyl ketone) decreased CpG ODN-induced IL-8 expression. Furthermore, stimulation of cells with CpG ODN enhanced κB-luciferase activity, and the activity was diminished by the overexpression of dominant negative mutants of MyD88 and IκBα. In addition, CpG ODN-induced IL-8 expression was markedly suppressed by U0126, but not by SB203580 and SP600125. Moreover, CpG ODN activated ERK phosphorylation in a time-dependent manner. These data demonstrate that CpG ODN-induced IL-8 expression was mediated through TLR9, MyD88, NF-κB, and ERK pathways in MDPC-23 cells and suggest a possible role for the CpG DNA-mediated immune response in odontoblasts with involvement of TLR9, MyD88, and ERK pathways in this process.
    Journal of endodontics 06/2012; 38(6):780-5. · 2.95 Impact Factor
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    ABSTRACT: This study compared the dental curricula at dental schools in China and Japan. A survey was conducted in representative dental schools in China and Japan. It was found that, in China and Japan where dental schools recruit students directly from high schools, more attention is paid to introduction of early professional education. Most dental schools in Japan arrange dental subjects for their students from the first through the fourth years, while in China, only a few dental schools take this path although many of them are currently making changes. It was also discovered that, in both countries, an increasing number of dental schools assign a specific dental subject to the same period with its relevant bioscience or biomedical counterparts, which makes it possible for them to enhance each other reciprocally in a positive way for students and consequently help dental students master the related topics.
    Journal of dental education 06/2012; 76(6):765-73. · 0.99 Impact Factor
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    ABSTRACT: Stem cells from the apical papilla (SCAP) are a type of mesenchymal stem cells found in the developing tissue, apical papilla, of immature permanent teeth. Studies have shown that SCAP are likely to be a source of primary odontoblasts that are responsible for the formation of root dentin. Basic fibroblast growth factor (bFGF) is a signaling molecule and pleiotropic growth factor involved in tooth root development, and it promotes proliferation of a variety of cell types. The effects of bFGF on SCAP, however, have not been examined. We investigated the regulatory effects of bFGF on the proliferation and differentiation potential of human SCAP in vitro. Changes in the cell cycle and proliferation, colony-forming unit-fibroblastic formation, alkaline phosphatase (ALP) activity, osteogenic/dentinogenic differentiation, and stem cell gene makers of SCAP, cultured in the presence or absence of bFGF, were evaluated. Treatment with 5 ng/mL bFGF significantly increased SCAP proliferation and their colony-forming unit-fibroblastic formation efficiency. The growth factor also increased the expression of STRO-1 and the stem cell gene makers Nanog, Oct4, Sox2, and Rex1 in SCAP. In contrast, bFGF reduced the ALP activity, mineral nodule formation, and the expression of ALP, osteocalcin, bone sialoprotein, and dentin sialophosphoprotein. When SCAP cultures were expanded in the presence of bFGF for 1 week, subsequent stimulation of the osteogenic/dentinogenic condition resulted in enhanced differentiation. Under certain conditions, bFGF enhances SCAP stemness by up-regulating stem cell gene expression, increasing proliferation ability, and potentiating differentiation potency.
    Journal of endodontics 05/2012; 38(5):614-22. · 2.95 Impact Factor
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    ABSTRACT: Vertical root fractures (VRFs) in teeth without endodontic treatment are relatively uncommon. The diagnosis is based on clinical and radiographic presentations. It might be difficult to detect VRFs in non-endodontically treated molars by conventional radiographs in certain situations because of the limitations of 2D images and many others factors such as the VRFs being in their early stages. Root morphology variation and the orientation of VRFs can influence conventional radiographic detection and the interpretation of a radiolucent fracture line. The four case reports presented here describe and discuss the use of cone-beam computed tomography (CBCT) in successfully diagnosing VRFs based on direct visualization of radiolucent lines, especially those suspected from routine conventional radiographs, as well as their symptoms and clinical findings. CBCT also provides more information on the presence of VRFs.
    Dental Traumatology 11/2011; 28(4):329-33. · 1.00 Impact Factor
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    ABSTRACT: Diagnosis of root fractures is generally based on clinical and radiographic presentations. This case report aims to detect horizontal/oblique root fractures in posterior teeth using a combination of conventional radiographs and cone-beam computed tomography (CBCT). Three maxillary first molars with horizontal/oblique root fractures in the palatal roots are presented. More detailed information on root fractures can be obtained using CBCT compared with conventional radiography. As such, CBCT might be a useful complementary diagnostic method to conventional radiography in cases of suspected horizontal/oblique root fractures.
    Dental Traumatology 08/2011; 27(6):464-7. · 1.00 Impact Factor
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    ABSTRACT: Runx2, of the Runx family, is an essential transcription factor that controls bone and tooth development by regulating osteoblast and odontoblast differentiation. However, the function of Runx2 in late stage odontoblast differentiation is not clear. We studied the function of Runx2 in dentinogenesis by generating transgenic mice expressing Runx2 specifically in odontoblasts. We observed dentin formation in postnatal day 3 (P3), P7 and P28 mice and measured the expression levels of Runx2 and matrix proteins in dentin. The odontoblasts in transgenic mice (Tg) lost their tall columnar shape and polarization and dentinal tubules were absent. The dental pulp chamber was dramatically enlarged and the dentin in Tg mice was thinner. Osteoblast-like cells were seen instead of normal odontoblasts and were embedded in a bone-like matrix, indicating that dentin formation was replaced with bone. Predentin was disorganized possessing lacunae that contained odontoblasts. The mandibular molars of Tg mice showed noticeable defects by Micro-CT. Using quantitative real-time PCR, the expression of dentin matrix proteins, particularly dentin sialophosphoprotein (DSPP), was found to be upregulated in 3-day-old Tg mice and downregulated at 1 month of age. These findings indicate that Runx2 inhibited odontoblast terminal differentiation and induced transdifferentiation of odontoblasts to osteoblasts at the late cell differentiation stage. Therefore, Runx2 should be inhibited in odontoblasts to encourage normal cell maturation, differentiation and dentinogenesis.
    Biochemical and Biophysical Research Communications 06/2011; 410(3):698-704. · 2.28 Impact Factor
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    ABSTRACT: Dental caries is a common oral bacterial infectious disease of global concern. Prevention and treatment of caries requires control of the dental plaque formed by pathogens such as Streptococcus mutans and Streptococcus sobrinus. Pleurocidin, produced by Pleuronectes americanus, is an antimicrobial peptide that exerts broad-spectrum activity against pathogenic bacteria and fungi. Moreover, pleurocidin shows less hemolysis and is less toxic than other natural peptides. In the present study, we investigated whether pleurocidin is an effective antibiotic peptide against common cariogenic microorganisms and performed a preliminary study of the antimicrobial mechanism. We assayed minimal inhibitory concentration (MIC), minimal bactericide concentration (MBC) and bactericidal kinetics and performed a spot-on-lawn assay. The BioFlux system was used to generate bacterial biofilms under controllable flow. Fluorescence microscopy and confocal laser scanning microscopy (CLSM) were used to analyze and observe biofilms. Scanning electron microscopy was used to observe the bacterial membrane. MIC and MBC results showed that pleurocidin had different antimicrobial activities against the tested oral strains. Although components of saliva could affect antimicrobial activity, pleurocidin dissolved in saliva still showed antimicrobial effects against oral microorganisms. Furthermore, pleurocidin showed a favorable killing effect against BioFlux flow biofilms in vitro. Our findings suggest that pleurocidin has the potential to kill dental biofilms and prevent dental caries.
    Peptides 06/2011; 32(8):1748-54. · 2.52 Impact Factor
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    ABSTRACT: The purpose of this study was to quantitatively analyze the root canal morphology of three-rooted mandibular first molars by micro-computed tomography (micro-CT) scans. Twenty three-rooted mandibular first molars were scanned by micro-CT scans. The teeth were reconstructed three-dimensionally by software Mimics 10.01 (Materialise, Leuven, Belgium). The levels of the root apexes and furcations; the diameters; wall thicknesses; and tapers of the mesiobuccal (MB), mesiodistal (ML), distobuccal (DB) and distolingual (DL) canals were determined. The buccolingual/mesiodiatal (BL/MD) diameter ratios (ΔC) and the prevalence of long oval canals (ΔC > 2) at different levels were calculated. The level of distal furcations was significantly (P < .01) lower than that of MD furcations with an average of 1.09 mm. The buccal and lingual walls were significantly (P < .05) thicker than the mesial and distal for the MB, ML, and DB canals. Among four canals, the DL canal had the smallest mean value of ΔC at each level. The average BL taper was greater than the MD for each canal except the middle portion of the DL canal. The vertical length, width, BL/MD diameter ratio, wall thickness, and BL taper of the DB canals are on average greater than the DL canals. The MB, ML, and DB canals are more oval, whereas the DL canals are relatively rounder. The geometric data of root canals are useful for endodontic treatment on three-rooted mandibular first molars.
    Journal of endodontics 04/2011; 37(4):485-90. · 2.95 Impact Factor
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    ABSTRACT: This case series describes observations of 12 patients who developed horizontal root fractures in non-endodontically treated teeth. Using clinical and radiographic examination, horizontal fractures were observed in eight maxillary first molars, one maxillary second molar, one mandibular first premolar and four mandibular second premolars. A total of 12 teeth had clinically intact crowns and 2 had carious. Eight fractures of maxillary molars occurred in the palatal roots, while one fracture was observed in the distobuccal root. Eleven patients experienced pain from the affected teeth during mastication. Within the limits of this case series, it was concluded that these fractures were related to; root morphology, damaging masticatory habits and excessive occlusal forces.
    Dental Traumatology 02/2011; 27(2):152-5. · 1.00 Impact Factor
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    ABSTRACT: The photocatalytic degradation of E.coli membrane cell by ZnO nanowires was studied using field-emission scanning electron microscope(FE-SEM), fluorescence microscopy, and Attenuated total reflection fourier transform infrared(ATR-FTIR). The outer membrane of E.coli was removed completely in the presence of ZnO nanowires under UV irradiation, and the cells became twisted shapes without a mechanically strong network. After ZnO nanowires photocatalysis, the permeability of the treated cells increased to some degree that could be confirmed by quantum dots labeling technique. Structural changes in the cell wall membrane were revealed by the decay of the characteristic groups bands in ATR-FTIR spectra.
    Journal of Wuhan University of Technology-Mater Sci Ed 01/2011; 26(2):222-225. · 0.48 Impact Factor