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Fu-qiang Zhang

Publications and source records attributed to Fu-qiang Zhang.

At least 19 recordsLinked to original sources
PubMed2006

[The influence of bonding strength of denture soft reline resin by different surface treatments].

PURPOSE: This study evaluated the influence of bonding strength of heat-polymerized denture soft reline resin by 4 different surface treatments bonded to denture base resin. METHODS: Denture base resin (8mm in diameter and 15 mm in length) were fabricated from heat-polymerized acrylic resin (Densply). And heat-polymerized denture soft reline resin disks (Physio liner) were also made (4 mm thick and 10 mm diameter). Two denture base resins were bonded to the denture reline resin disk at the centure on the two sides of the disk. All the specimen were divided into 4 groups (n=10) with 3 different surface treatments: (1) no treatment(control), (2) sandblasted, (3) surface liner application, (4) surface liner application+sandblasted. Bond strength (MPa) was measured by tension bond testing at a 12.7 mm/min speed until the soft reline resin debonded from the base resin. Data were statistically analyzed by SPSS 10.0 software package for ANOVA. RESULTS: The mean bond strengths of group 1, 2, 3, 4 were 3.518, 2.834, 4.077, 3.852MPa respectively. The bonding strength of all the three groups showed significant difference (P<0.0014). The group with surface liner application showed significantly highest bonding strength, while the group with sandblasted showed the lowest bonding strength. CONCLUSIONS: The use of surface liner can significantly improve the bonding strength of heat-polymerized denture soft reline resin to the denture base resin, while the bonding strength decreased after using sandblasting.

Acrylic Resins↗
PubMed2006

[Culture and characteristics of porcine dental papilla cells (pDPCs) in vitro].

PURPOSE: To culture porcine dental papilla cells (pDPCs) and to study the cytobiological characteristics of the cells in vitro. METHODS: Dental papillae were collected from postnatal (1-3 days) pigs, then the pDPCs were isolated and cultured through the method of enzyme-digestion. Vimentin and cytokeratin (CK) were used to demonstrate the cells' mesenchymal derivation. Collagen I collagen III and dentin sialoprotein (DSP) were detected in pDPCs by immunohistochemistry. RESULTS: The pDPCs were well cultured in the medium of DMEM/F12 containing 10% FBS in vitro. Vimentin was positively expressed in pDPCs but CK was not. Collagen I, collagen III, and DSP were all positive in the plasma of the pDPCs. CONCLUSIONS: The pDPCs were successfully isolated and cultured in vitro. The pDPCs come from mesenchymal tissue and have the capability of synthesizing extracellular matrix (collagen I, collagen III, and DSP) of dentin-pulp complex. This study indicated that the pDPCs may have the potential to be used as seed cell in regeneration of dentin-pulp complex.

Animals↗
PubMed2006

[Effect of three kinds of rare earth oxides on chromaticity and mechanical properties of zirconia ceramic].

OBJECTIVE: To evaluate the colouration of zirconia ceramic by adding three kinds of rare earth oxides. The influence of the pigments concentration on the mechanical properties and the microstructure was also analyzed. METHODS: Added different concentrations of CeO(2), Er(2)O(3) and Pr(6)O(11) in tetragonal zirconia poly crystals stabilized with 3 mol% yttria (3Y-T2P) powder, compacted at 200 MPa using cold isostatic pressure, and sintered to 1 400 degrees C. The heating rate was 150 degrees C/h and the dwelling time was 2 hours. The chromaticity of sintered bodies was measured with chroma meter. The relative density, hardness, flexure strength and fracture toughness were investigated as well. The phase stability of the colorized and pure zirconia was evaluated by X-ray diffraction (XRD) using an automated diffractometer. The microstructures of the specimens were evaluated by scanning electron microscope (SEM). RESULTS: Several kinds of color achieved by the different pigments praseodym oxide, cerium oxide and erbium oxide were presented in the CIELab system. The a* value increased with the added amount of Er(2)O(3), while b* value rose with the increasing amount of CeO(2) and Pr(6)O(11). However, three pigments failed to decrease L* value and the sintered body appeared too bright. Adding three pigments influenced flexure strength of zirconia ceramic significantly, but had little influence on the hardness and fracture toughness. Microscopy revealed the relationship between the porosity and shapes of grains was correlated to strength of the diphase ceramics. No additional phase could be detected by XRD, except t-ZrO(2) in all colorized samples after sintering at 1 400 degrees C for 120 min. CONCLUSIONS: Zirconia ceramic can be colorized by CeO(2), Er(2)O(3), and Pr(6)O(11). Pigments even in a small amount influence the mechanical properties of the colorized zirconia material, which necessitates further investigation.

Coloring Agents↗
PubMed2006

[Non-invasive detection of metal casting defects using dental X ray machine].

PURPOSE: The purpose of this in vitro study is to find the best parameters in detecting the casting defects made of titanium, nickel-chromium and chromium-cobalt using dental X ray machine. METHODS: Casting sheets in different thickness (1.0 mm, 0.6 mm, 0.3 mm)were fabricated using of Ti, Ni-Cr and Cr-Co.Small pores on the surfaces were made with laser welder to simulate the internal porosity of the castings. Parameters of the dental X ray machine were adjusted to take films. The data were analyzed using SPSS12 software package for group t test. RESULTS: The thickness of Ti had no significant effect on the setting of the parameters of the dental X ray machine in detecting the defects of titanium castings (P>0.05), while the thickness of Ni-Cr and Cr-Co had significant effect on the setting of the parameters (P<0.05). CONCLUSION: Dental X ray machine can be used in detecting the defects of titanium casting sheets.

Chromium Alloys↗
PubMed2006

[Study on the mechanical properties of quartz fiber-reinforced composite for canal post].

PURPOSE: To study the mechanical properties of custom-made quartz fiber-reinforced epoxy resin composite for prefabricated post. METHODS: Composite rods of 5 experiment groups with different fiber contents were made of quartz fiber and epoxy resin.Flexural strengths, shear strengths and fiber contents were measured, corresponding elastic modulus were calculated, cross-section surface and fracture surface was viewed under SEM. Statistical analysis was carried out with one way analysis of variance(ANOVA) and Student-Newman-Keuls for the experimental groups. RESULTS: The flexural strength of composite rods increased with the increase of fiber content, within the limitations of this research, the flexural strengths ranged from 741 to 1165 MPa, corresponding fiber contents ranged from 53.3 to 78.6 Wt%, corresponding flexural strengths ranged from 36.7 to 50.4 MPa,corresponding elastic modulus ranged from 30.6 to 51.9 GPa, SEM showed that fiber distribution in resin was uniform, there was good adhesion between fiber and epoxy resin. ANOVA revealed significant differences of flexural strengths and shear strengths between the experimental groups and control group (P<0.01), Student-Newman-Keuls analysis showed significant differences of flexural strengths and shear strengths between the experimental groups(P<0.01). CONCLUSION: The custom-made quartz fiber-reinforced epoxy resin composite can be used for prefabricated post with good mechanical properties.

Composite Resins↗
PubMed2006

[The effect of the position of artificial premature on mandible moving track during opening movement].

PURPOSE: The purpose of this study was to observe the effect of the position of premature on track of mandibular incisal point during opening movement. METHODS: The changes of the track of mandibular incisal point along with the change of premature position were recorded by Arcus DigMa mandibular moving track analysis system. The relativity between the premature position and mandibular incisal point moving track on arrowy axis, vertical axis and horizontal axis was analyzed. Regression analysis was used for linear correlation between premature position and mandible opening moving track. RESULTS: The results showed that along with the retrusion of premature, the moving distance of mandibular incisal point tended to increase on arrowy axis, while decrease on vertical axis and lean to the contralateral side on horizontal axis. The linear regression equation of mandibular incisal point moving distance on vertical axis along with the premature position was: y=34.7095-0.1590x(1), delta=0.5549, P<0.001. CONCLUSION: The position of premature influenced the track of mandibular incisal point during opening movement significantly. With the retrusion of premature, the mandible opening moving track tended to be more posterior and shifting to the contralateral side, and the opening dimension tended to decrease. There was linear correlation between premature position and mandible moving track on the vertical axis.

Dental Occlusion↗
PubMed2006

[Stress analyses and comparison of the Kennedy III dentition defect restored with removable partial denture].

PURPOSE: To investigate the stress distribution of the abutment and oral mucosa in Kennedy III, restored with removable partial dentures, either unilateral or bilateral designed. METHODS: Five FEA models were established for the partial edentulous and RPDs, which were divided into group A and group B. According to the denture design, bilateral (B) or unilateral (A) designed. The 3-D finite element analyses were proceeded and calculated with the help of the software ANSYS. Paired t test was used for statistical analysis using SAS 6.2 software package. RESULTS: The maximum stress appeared near the cervical mesial area of the first bicuspid and the second molar. There was no significant difference between the two groups in the stress distribution of the abutment and oral mucosa (P>0.05). CONCLUSION: In regard to the stress of the abutments, unilateral designs have no excess stress formed when RPD was used to restore Kennedy III dentition defect.

Bicuspid↗
PubMed2006

[Three-dimensional finite analysis of the application of attachment for restoration of unilateral maxillary defect].

PURPOSE: To study the stress of the application of attachment for restoration of unilateral maxillary defect. METHODS: Using the 3-D FE model of the unilateral maxillary defect, two different 3-D FE models of the application of attachment framework for restoration of different unilateral maxillary defects (attachment on the mesial side of the central incisor or canine) were designed and established. RESULTS: The area of stress concentration of the two prostheses were on the palatal base near the position of the anterior teeth. The stress was on the posterior teeth of the healthy side. When the attachment was on the mesial side of the central incisor, the stress of the mesial surface of the central incisor was 1.306MPa, and the stress concentration was at the junction of the attachment and the lingual guide plane. When the attachment was on the mesial of the canine, the stress of the mesial surface of the canine was 0.797MPa, and stress concentration was at the corner of the front and bottom of the lingual guide plane. CONCLUSIONS: The application of attachment for restoration of unilateral maxillary defect meets the biomechanical demands without increasing the stress load on the abutment. And further study of the design of the attachment framework should be done.

Dental Abutments↗
PubMed2006

[Establishing three-dimensional reconstruction and measuring system for complete denture occlusion].

PURPOSE: This study was designed to investigate the digital method of locating and reconstructing the occlusal relationship between the upper and lower full dentures. METHODS: The artificial teeth occlusal surfaces of ten complete dentures were scanned by non-contact laser scanner and were reconstructed by three-dimensional technique. With placements of 6 standard steel ball, the three-dimensional position relationship of upper and lower full dentures were studied and reconstructed in centric occlusal position. RESULTS: The three-dimensional reconstruction and measuring system of complete denture occlusion was preliminarily established in this study. CONCLUSIONS: This study focused on exploiting a new system to quantitatively reconstruct the occlusal relationship of complete denture in centric occlusion. And the study may set a methodological foundation of further three-dimensional research for complete denture occlusion.

Dental Occlusion↗
PubMed2006

[Effects of electroacupuncture of low frequency on heroin-seeking behavior and FosB protein expression in relative brain regions].

OBJECTIVE: To observe effects of electroacupuncture (EA) of low frequency on heroin-seeking behavior and FosB protein expression in relative brain regions so as to explore the mechanism of EA. METHODS: Rat model of relapsing into heroin was established with progressive fixed ratio program, and model rats were randomly divided into 3 groups: a "Sanyinjiao" needle-retention control group, a low frequency and weak EA group, and a low frequency and strong EA group. Heroin-seeking behavior was elicited by conditional clue and small dose of heroin; FosB protein expression was investigated with immunohistochemical technique. RESULTS: After treatment, the heroin-seeking behavior induced by conditional clue decreased in the needle-retention control group and the weak EA group, and the heroin-seeking behavior induced by small dose of heroin in the weak EA group significantly reduced as compared with the control group, and FosB protein expression in the nucleus accumbens septi, globus pallidus, basolateral amygdaloid nucleus significantly decreased in the weak EA group, and did not significantly change in the strong EA group; the activity induced by heroin increased as compared with those in the control group and the weak EA group. CONCLUSION: EA of low frequency and low intensity can cure the heroin-seeking behavior, which is correlated with regulating nervous adaptation of nucleus accumbens septi, basolateral amygdaloid nucleus, etc..

Amygdala↗
PubMed2005

[Identification and comparison of neutralizing epitopes of glycoprotein E(rns) of classical swine fever virus].

Structural and envelope glycoprotein E(rns) (gp48) of classical swine fever virus (CSFV) is the second antigenic protein being responsible for eliciting neutralizing antibodies and conferring protective immunity. Infection of cells with CSFV is mediated by the interaction of glycoprotein E(rns) and E2 with the cell surface receptors. The glycoprotein E(rns) has been shown to contain RNase activity, which plays a role in the viral life cycle and is also involved in virus neutralization. Neutralizing epitopes of glycoprotein E(rns) had been mapped by screening a 12-mer random peptide phage display library using the neutralizing monoclonal antibodies (MAbs) 1B5, b4-22 and 24/16, raised against CSFV strain alfort T bingen and reacted with glycoprotein E(rns). Three major epitope (mimotope) motifs, WxNxxP, DKNR (Q) G and A (T) CxYxKN (around amino acid position aa351-aa356 or aa348-aa350, aa384-aa386 and aa322-aa323, aa380-aa386 of glycoprotein E(rns) of CSFV) were identified respectively and characterized immunologically by the MAbs, 1b5, b4-22 and 24/16. MAbs b4-22 and 24/16 shared a part of binding motif sequence KN, and recognized the similar antigenic domain on the glycoprotein E(rns) but showed a distinct pattern of flank sequence and reactivities with the mimotopes by Western blot and inhibition of immunofluorescent antibody analysis.

Amino Acid Sequence↗
PubMed2005

[Ectopic osteogenic ability of BMSCs on various scaffold materials in nude mice].

PURPOSE: To explore the ectopic osteogenic abilities of bone marrow stromal cells (BMSCs) on different scaffold materials in nude mice. METHODS: Canine BMSCs in vitro cultured were seeded at the density of 1x10(6)cells/cm(2) onto scaffolds of freeze-dried demineralized bone matrix (fdDBM), tricalcium phosphate (TCP), 200microm coralline hydroxyapatite (CH200) and 500microm coralline hydroxyapatite (CH500). The cell adherence and growth on the materials were examined by SEM and H&E staining after 4 to 7 days of in vitro culturing. To observe the ectopic osteogenic capacity, four 10mmx5mmx2mm cell/scaffold complexes (fdDBM, TCP, CH200, CH500) and a blank control scaffold (fdDBM only) were implanted subcutaneously into each of athymic mice (n=8). The implants were harvested after 9 weeks and H&E stained. Newly formed trabecular bone volume (TBV) was measured by IMAGER-PRO PLUS software, and statistical analysis was performed by ANOVA with SAS software. RESULTS: Canine BMSCs adhered to all 4 types of scaffolds and spread well in their pores 7-8 days after seeding. Athymic subcutaneous ectopic osteogenesis were observed in all the specimens of TCP, CH200, CH500 but were observed only in 75% of BMSCs/fdDBM and 25% of fdDBM. The TCP group showed significant higher TBV percentage (28.2%+/-2.86) than CH200 group (24.1%+/-4.12) and CH500 group (18.1%+/-4.66) (P<0.01). CONCLUSIONS: BMSCs adhered to all 4 scaffolds. When combined with BMSCs, TCP exhibited the greatest osteogenic potential, which indicates that it might be an excellent scaffold material in the field of bone tissue engineering. Supported by National 973 Project (G1999054300) and National Natural Science Foundation of China(30271426).

Animals↗