Objective:To establish three-dimensional(3D) finite element models of the first mandibular molar restored with three post and core systems.Methods:Three 3D finite element models of the restored first mandibular molars were constructed by using CT image reconstruction technique.Then MIMICS software was used to separate the areas and to finish 3D calculation.GEOMAGIC software was applied to modify and generate a NURBS surface in each patch.All components of the models were assembled under the ANSYS preprocessor.Specific materials parameters were selected to simulate the various restoration and dentin status.Results:The 3D finite element models of restored first mandible molars were successfully established,which were consistent to the situation observed in the clinical environment.Conclusion:It is a practical and accurate method to establish three-dimensional finite element models by CT image reconstruction technique and reverse engineering software MIMICS and GEOMAGIC.

Objective To explore the association of immune suppression with the severity of HBV-related acute-on-chronic liver failure(ACLF) patients.Methods From August 2009 to April 2010 in Shanghai Public Health Clinical Center, the peripheral blood samples and clinical data of 27 HBV-related ACLF patients (ACLF group), 28 patients wit h chronic active hepatitis B (CHB group)and 8 healthy individuals (Control group) were collected.APACHE Ⅲ score and the grade of hepatic encephalopathy were as quantitative index to evaluate the severity degree of the disease.The absolute counts of the subsets of T lymphocytes and human leukocyte antigen (HLA)-DR expression on the surface of monocyte in patients' peripheral blood were examined by flow cytometry, the proinflammatory cytokines and anti-inflammatory cytokines(IFN-γ, TNF-α, IL-2, IL-4, IL-10) in patients' plasma were detected by cytometric bead array (CBA) kit.The data was analyzed with SPSS 16.0 software.Results Compared with CHB group and control group, the level of anti-inflammatory eytokire IL-10 markedly increased ir HBV-related ACLF patients (Z= -4.279 ,U= 124, P＜0.01;Z= - 3.871, U= 9.5, P= 0.0001 ), however the level of pro-inflammatory cytokines IFN-γ、 TFN-α、IL-2 、 IL-4 in plasma were at low limit of detectable value.Meanwhile the expression quantity of HLA-DR on the peripheral blood monocytes significantly down-regulated (Z= -4.714, U= 98, P＜0.01;7= - 4.086, U = 4, P＜ 0.01), and there was negative correlation between HLA-DR expression quantity and APACHE Ⅲ score (R2 =0.2667, P=0.0167).In addition, the absolute counts of CD4+T lymphocytes in adaptive immune cells significantly decreased (Z= -4.411, U= 116, P＜0.01; Z=-3.575, U= 17, P= 0.0004).Conclusions The immune system of HBV-related ACLF patients displays immune dysfunction like monocyte function inhibition; CD4+ T lymphocytes depletion and high level of anti-inflammatory eytokines, the persistent down-regulation of the HLA-DR expression on monocyte is an indicator for the severity of disease.

Objective To investigate the clinical features and incidence of depression in patients with different lo-cations and pathological types of brain tumors. Methods Hamilton Depression Scale (HRSD) was used to assess the de-pression in 140 patients with brain tumor before and after operation. Results The preoperative mean depression rating score was 15.36 ± 6.52 and the prevalence rate of depression was 50 cases (35.7%) in 140 patients with brain tumor. The postoperative mean score of depression was 9.71 ± 5.55 and the prevalence rate of depression was 9 cases (6.4%) in 140 patients with brain tumor. The postoperative depression score and the prevalence rate was significantly decreased after op-eration (P<0.05)(χ2=36.10,P<0.05). The postoperative depression score in either benign or malignant brain tumors was significantly lower after than before operation(all P<0.05)The postoperative depression score in either the left or right or bilateral brain lesions were significantly decreased after than before operation(all P<0.05).Conclusion Pa-tients with brain tumors have different degrees of depression in perioperative. Depression may be associated with brain tu-mour pathological types and lesion sites in patients with brain tumors.

This paper is aimed to investigate the effect of rest-inserted loading on the mechanosensitivity of osteocytes. In the investigation, cultured MLO-Y4 osteocyte-like cells were strained on cyclic compressive force (CCF) by the self-made compressive loading device. Then we observed the effect of different rest periods-inserted loading (5 s, 15 s, 30 s, respectively) on the mechanosensitivity of osteocytes. We then determined the levels of secreted nitric oxide (NO) and prostaglandin E2 (PGE2) by Griess method and enzyme linked immunosorbent assay (ELISA), respectively. We then stained the cytoskeleton F-actin using immunofluorescence. We found that the expressions of NO and PGE2 in rest-inserted strained groups (> 15 s) were significantly increased compared to those in the continuous strained group. And rest-inserted loading promoted the parallel alignment of stress fibers. It indicates that rest-inserted loading could promote the mechanosensitivity of osteocytes, and this might be related to the parallel alignment of stress fibers.
Actins ; metabolism ; Animals ; Cell Culture Techniques ; Cell Line ; Cytoskeleton ; metabolism ; Dinoprostone ; secretion ; Mice ; Nitric Oxide ; secretion ; Osteocytes ; secretion ; Stress, Mechanical

Objective To study apoptosis and antigen presentation changes of monocytes in HBV-related acute-on-chronic liver failure (ACLF) patients under immune dysfunction state.Methods Peripheral blood samples of 26 HBV-related ACLF patients (ACLF group),20 active chronic hepatitis B patients (CHB group) and 18 healthy individuals (control group) were collected.The changes of apoptosis and proliferation (Ki67) in monocytes and the expression of surface markers including human leukocyte antigen (HLA)-DR and B7 molecules (CD86) of monocytes were analyzed by flow cytometry. Results The percentage of Annexin V expressed monocytes of ACLF group (64％) was significantly higher than that of CHB group (28％) and control group (20％),and the difference was statistically significant (x2 value was 11.75 and 27.23 ; both P＜0.01),which indicated that monocytes apoptosis increased.The Ki67 expression in monocytes of ACLF group was lower than that of CHB group and control group,and the difference was statistically significant (x2 value was 4.71 and 4.83; both P＜ 0.05),which indicated that activated monocytes reduced. The mean fluorescence intensity (MFI) of HLA-DR and CD86 of monocytes in ACLF group was 22.85 and 11.63,which was significantly lower than that of CHB group and control group,indicating the antigen presentation ability of monocytes injured. The percentage of Annexin Ⅴ positive monocytes in survivals (62 ％ ) was significantly higher than that of dead patients (46 ％ ) in ACLF group.Conclusion In HBV-related ACLF patients under immune dysfunction state,the apoptosis of peripheral blood monocytes increased,and the quantity of activated cells reduced,resulting in the decline of the antigen presentation ability of monocytes.

PURPOSE: . To compare the sagittal condylar inclination (SCI) in dentate individuals measured by the different methods with mechanical articulator (MA), virtual articulator (VA), and a jaw tracking device (JTD) system. MATERIALS AND METHODS: . A total of 22 healthy dentate participants were enrolled in this study. For MA workflow, the SCI was obtained by a semi-adjustable articulator with protrusive interocclusal records. The SCI was also set on a VA by aligning intraoral scan (IOS) with cone beam computed tomography (CBCT) and facial scan (FS), respectively. These virtual workflows were conducted in a dental design software, namely VAIOS-CBCT and VAIOS-FS . Meanwhile, a JTD system was also utilized to perform the measurement. Intraclass correlation was used to assess the repeatability within workflows. The bilateral SCI values were compared by Wilcoxon matched-pairs signed rank test for each workflow, and Kruskal-Wallis test and post hoc p-value Bonferroni correction were used to compare the differences among four workflows. The agreement of VAIOS-CBCT , VAIOS-FS , and JTD compared with MA was evaluated by Bland-Altman analysis. RESULTS: . Intraclass correlation of the SCI revealed a high degree of repeatability for each workflow. There were no significant differences between the left and right sides (P > .05), except for VAIOS-CBCT (P = .028). Significant differences were not found between MA and VAIOS-FS (P > .05). Bland-Altman plots indicated VAIOS-CBCT , VAIOS-FS , and JTD were considered to substitute MA with high 95% limits of agreement. CONCLUSION . The workflow of VAIOS-FS provided an alternative approach to measure the SCI compared with MA.

OBJECTIVETo evaluate the biomechanical effects of intracellular changes on the voltage-gated sodium channels (VGSCs) on trigeminal ganglion neuron (TRGN).

METHODSTRGN cells were acutely isolated from the neonatal SD rats. The voltage-dependent currents of the VGSCs on these neurons were elicited and analyzed by whole-cell patch-clamp recordings and the intracellular anisotonicity stimuli was established by adjusting the content of pipette solution. The effects of hypo-(260 mOsm) and hypertonic (350 mOsm) osmolarity on the activation and inactivation kinetics of VGSCs on TRGN were evaluated, compared with the normal intracellular environment.

RESULTSThe results demonstrated that intracellular hypotonic stimuli could influence both the activation and inactivation characteristics of VGSCs currents, including the membrane potential at half inactivation (V0.5) of the G-V and inactivation curves had obvious statistics significance (P<0.05) between hypotonicity (260mOsm) and isotonicity (306mOsm). However, only inactivation properties changed under intracellular hypertonic effects, including inactivation rate and k value.

CONCLUSIONIt suggests that the kinetics of VGSCs on TRGN can be modulated both by intracellular hypo- and hypertonic with different characteristics.

Animals ; Cells, Cultured ; Membrane Potentials ; Neurons ; Osmolar Concentration ; Patch-Clamp Techniques ; Rats ; Rats, Sprague-Dawley ; Sodium Channels ; Trigeminal Ganglion

PURPOSE: To measure the surface loss of dental restorative zirconia and the short-term bond strength between an indirect composite resin (ICR) and zirconia ceramic after various sandblasting processes. MATERIALS AND METHODS: Three hundred zirconia bars were randomly divided into 25 groups according to the type of sandblasting performed with pressures of 0.1, 0.2, 0.4 and 0.6 MPa, sandblasting times of 7, 14 and 21 seconds, and alumina powder sizes of 50 and 110 microm. The control group did not receive sandblasting. The volume loss and height loss on zirconia surface after sandblasting and the shear bond strength (SBS) between the sandblasted zirconia and ICR after 24-h immersion were measured for each group using multivariate analysis of variance (ANOVA) and Least Significance Difference (LSD) test (alpha=.05). After sandblasting, the failure modes of the ICR/zirconia surfaces were observed using scanning electron microscopy. RESULTS: The volume loss and height loss were increased with higher sandblasting pressure and longer sandblasting treatment, but they decreased with larger powder size. SBS was significantly increased by increasing the sandblasting time from 7 seconds to 14 seconds and from 14 seconds to 21 seconds, as well as increasing the size of alumina powder from 50 microm to 110 microm. SBS was significantly increased from 0.1 MPa to 0.2 MPa according to the size of alumina powder. However, the SBSs were not significantly different with the sandblasting pressure of 0.2, 0.4 and 0.6 MPa. The possibilities of the combination of both adhesive failure and cohesive failure within the ICR were higher with the increases in bonding strength. CONCLUSION: Based on the findings of this study, sandblasting with alumina particles at 0.2 MPa, 21 seconds and the powder size of 110 microm is recommended for dental applications to improve the bonding between zirconia core and ICR.
Adhesives ; Aluminum Oxide ; Ceramics ; Immersion ; Microscopy, Electron, Scanning ; Multivariate Analysis

On page 219, there was an error in the Fig. 5.

PURPOSE: . The purpose of this in vitro study was to assess whether scanning strategies of virtual interocclusal record (VIR) affect the accuracy of VIR during intraoral scanning. MATERIALS AND METHODS: . Five pairs of reference cubes were added to the digital upper and lower dentitions of a volunteer, which were printed into resin casts. Subsequently, the resin casts were articulated in the maximal intercuspal position in a mechanical articulator and scanned with an industrial computed tomography system, of which the VIR was served as a reference VIR. The investigated VIR of the upper and lower jaws of the resin master cast were recorded with an intraoral scanner according to 9 designed scanning strategies.Then, the deviation between the investigated VIRs and reference VIR were analyzed, which were measured by the deviation of the distances of six selected reference points on the upper reference cubes in each digital cast to the XY-plane between the investigated VIRs and reference VIR. RESULTS: . For the deviation in the right posterior dentitions, RP group (only scanning of right posterior dentitions) showed the smallest deviation. Besides, BP group (scanning of bilateral posterior dentitions) showed the smallest deviation in the left posterior dentitions. Moreover, LP group (scanning of left posterior dentitions) showed the smallest deviation in the anterior dentitions. For the deviation of full dental arches, BP group showed the smallest deviation. CONCLUSION . Different scanning strategies of VIR can influence the accuracy of alignment of virtual dental casts. Appropriate scanning strategies of VIR should be selected for different regions of interest and edentulous situations.