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PURPOSE: To evaluate the effect of different bonding procedure and different root region on the bond strength of fiber posts to root canal. METHODS: Forty -two extracted intact human maxillary central incisors were endodontically treated with post spaces be prepared and divided into 6 groups randomly. The fiber posts were then luted with the following different bonding procedures. Group I : total etch dentin bonding agent Luxabond + self-adhesive system Rely X™ Unicem; Group I : total etch dentin bonding agent Luxabond + dual-cure rein cement Luxacore; Group HI: self etch dentin bonding agent Contax + self -adhesive system Rely X ™ Unicem; Group IV :self etch dentin bonding agent Contax + dual-cure rein cement Luxacore; Group V: self-adhesive system Rely X ™ Unicem; Group VI:dual-cure rein cement Luxacore. After dowel cementation, thin-slice push-out test was performed. The bonding interface and dentin surface were examined under scanning electron microscope. The data was statistically analyzed using SPSS13.0 software package. RESULTS: The results showed that different bonding procedures had significant different impacts on the bond strength (P<0.05). Group I and Group IH had significantly higher bond strength compared with other groups. Resin tags of dentin bonding interface were observed in Group I and Group II and intimate adaptations of resin cement with the substrate were revealed. CONCLUSIONS: Coupled with total etch or self etch dentin bonding agent, self- adhesive system Rely X™ Unicem can improve the bonding strength of fiber posts obviously. Supported by Research Fund of Science and Technology Committee of Xuhui District (SHXH201130). [ABSTRACT FROM AUTHOR]

PURPOSE: To investigate the effect of silica coating by sol-gel process on bonding strength of zirconia ceramics to dentin. METHODS: Blocks of sintered zirconia ceramics were cut and randomly divided into 4 groups, 16 slices in each group. Each group was subject to one of the 4 kinds of surface treatment (control group, sandblasting, sandblasting +silicone, sandblasting + silica coating + silicone) and then bonded to dentin with resin cement. After preservation in 37°C distilled water for 24 hours, the shear bonding strength of these specimens was tested and the data was analyzed with SAS6.12 software package for analysis of variance. The surface modality of the ceramics was observed under scanning electron microscopy (SEM). RESULTS: The group of sandblasting+ silica coating + silicone attained the highest shear bonding strength, which was significantly different from the other groups (P=0.000); There was no significant difference between the sandblasting and sandblasting + silicone group (P=0.827), which was significantly different from the control group (P=0.001). CONCLUSION: Silica coating by sol-gel process, coupled with silicone, can significantly increase the bonding strength of zirconia ceramics to dentin. [ABSTRACT FROM AUTHOR]

PURPOSE: To investigate the adequate luting cements for zirconia ceramics to dentin. METHODS: Blocks of sintered zirconia ceramics were randomly divided into 4 groups with 8 slices in each. Alter saliva immersion, airborne-particle abraded ceramic specimens were cleaned with phosphoric acid gel (containing 35% phosphoric acid) and then bonded to dentin with these four kinds of luting cements. After preserved in 37°C distilled water for 24 hours, the shear bonding strength of these specimens was tested and the data was analyzed with SPSS 12.0 software package. RESULTS: The Multilink Automix could attain the highest shear bonding strength and the 3M RelyX™ Unicem Aplieap™ could attain higher shear bonding strength, which were both significantly higher than in the Tokuso Ionomer and Shofu Polycarboxylate Cement groups (P<0.05). CONCLUSION: Total etching resin luting cement is an ideal option to the bonding of zirconia ceramics and can provide a strong bonding. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effects of five different surface treatments on the bond strength between fiber posts and resin cement., Methods: Fifty fiber posts were randomly divided into 5 groups for different surface treatments. Group A was treated with silane coupling agent (Clearfil Porcelain Bond Activator,Kuraray); Group B was treated with silane coupling agent and then coated with dentin bonding agent (Clearfil SE Bond,Kuraray); Group C was immersed in 30% H(2)O(2); Group D was immersed in 30 % H(2)O(2) and then treated with silane coupling agent; Group E received no surface treatment (control group). After bonding to resin cement, each group was then divided into 2 subgroups equally, while one group was stored in sodium chloride for 24 h at 37 degrees centigrade, and the other group was stored in sodium chloride for 24 h at 37 degrees centigrade and then subjected to thermal cycling for 10000 times. Microtensile bond strengths were tested and the data was statistically analyzed using SPSS17.0 software package., Results: The microtensile bond strength before thermal cycling was (6.7±0.7) MPa for group A,(14.4±1.1) MPa for group B,(10.7±0.9) MPa for group C,(16.0±1.0) MPa for group D and (6.7±1.0) MPa for group E. After thermal cycling, the microtensile bond strength was (6.7±0.7) MPa for group A, (13.1±0.7) MPa for group B, (9.0±0.7) MPa for group C, (15.0±0.9) MPa for group D and (5.6±0.7) MPa for group E. The results showed that surface treatments had significant impact on the bond strength (P<0.05). There was no significant difference between group A and group E. Group D had the highest bond strength compared with the other groups. Microtensile bond strengths were significantly different before and after thermalcycling treatment in each group (P<0.05)., Conclusions: Thermocycling treatment decreases the bond strength of fiber posts to resin cement with these 5 surface treatments. Coupled with 30 % H(2)O(2) solution and silanization, the bonding strength of fiber posts to resin cement can increase significantly.

Purpose: To evaluate the effect of different bonding procedure and different root region on the bond strength of fiber posts to root canal., Methods: Forty-two extracted intact human maxillary central incisors were endodontically treated with post spaces be prepared and divided into 6 groups randomly. The fiber posts were then luted with the following different bonding procedures. Group I: total etch dentin bonding agent Luxabond + self-adhesive system Rely XTM Unicem; Group II: total etch dentin bonding agent Luxabond + dual-cure rein cement Luxacore; Group III: self etch dentin bonding agent Contax + self -adhesive system Rely X TM Unicem; Group IV :self etch dentin bonding agent Contax + dual -cure rein cement Luxacore; Group V:self-adhesive system Rely X TM Unicem; Group VI:dual-cure rein cement Luxacore. After dowel cementation, thin-slice push-out test was performed. The bonding interface and dentin surface were examined under scanning electron microscope. The data was statistically analyzed using SPSS13.0 software package., Results: The results showed that different bonding procedures had significant different impacts on the bond strength (P<0.05).Group I and Group III had significantly higher bond strength compared with other groups. Resin tags of dentin bonding interface were observed in Group I and Group II and intimate adaptations of resin cement with the substrate were revealed., Conclusions: Coupled with total etch or self etch dentin bonding agent, self- adhesive system Rely X TM Unicem can improve the bonding strength of fiber posts obviously.

The Slit-Robo GTPase-activating proteins (srGAPs) play an important role in neurite outgrowth and axon guidance; however, little is known about its role in nerve regeneration after injury. Here, we studied the expression of srGAPs in mouse dorsal root ganglia (DRG) following sciatic nerve transection (SNT) using morphometric and immunohistochemical techniques. Reverse transcriptase polymerase chain reaction and Western blot analysis indicated that srGAP1 and srGAP3, but not srGAP2, were expressed in normal adult DRG. Following unilateral SNT, elevated mRNA and protein levels of srGAP1 and srGAP3 were detected in the ipsilateral relative to contralateral L(3-4) DRGs from day 3 to day 14. Immunohistochemical results showed that srGAP1 and srGAP3 were largely expressed in subpopulations of DRG neurons in naïve DRGs. However, after SNT, srGAP3 in neurons was significantly increased in the ipsilateral relative to contralateral DRGs, which peaked at day 7 to day 14. Interestingly, DRG neurons with strong srGAP3 labeling also coexpressed Robo2 after peripheral nerve injury. These results suggest that srGAPs are differentially expressed in murine DRG and srGAP3 are the predominant form. Moreover, srGAP3 may participate in Slit-Robo signaling in response to peripheral nerve injury or the course of nerve regeneration., (Copyright © 2012 Wiley Periodicals, Inc.)

Objective: To study The protective effect of puerarin on Abeta(25-35)-induced PC12 cell injury., Methods: PC12 cells were treated with puerarin for 0.5 h, then incubated with Abeta(25-35) (50 micromol/L) for 24 h to investigate the production of reactive oxygen species (ROS), mitochondrial membrane potential levels and Caspase-3 activation; The expressions of Bax, bcl-2 were measured by Western Blotting., Results: Preincubation of the cell with puerarin could inhibit the ROS and increase mitochondrial membrane potential levels. Puerarin was also found to increase the Bcl-2/Bax ratio and reduce Caspase-3 activation., Conclusion: Puerarin may act as an intracellular ROS scavenger, and its antioxidant properties may protect against Abeta(25-35)-induced cell injury.

Purpose: To investigate the adequate luting cements for zirconia ceramics to dentin., Methods: Blocks of sintered zirconia ceramics were randomly divided into 4 groups with 8 slices in each. After saliva immersion,airborne-particle abraded ceramic specimens were cleaned with phosphoric acid gel(containing 35% phosphoric acid) and then bonded to dentin with these four kinds of luting cements. After preserved in 37 degrees centigrade distilled water for 24 hours, the shear bonding strength of these specimens was tested and the data was analyzed with SPSS12.0 software package., Results: The Multilink Automix could attain the highest shear bonding strength and the 3M RelyXTM Unicem AplicapTM could attain higher shear bonding strength, which were both significantly higher than in the Tokuso Ionomer and Shofu Polycarboxylate Cement groups(P<0.05)., Conclusion: Total etching resin luting cement is an ideal option to the bonding of zirconia ceramics and can provide a strong bonding.

Purpose: To investigate the effect of silica coating by sol-gel process on bonding strength of zirconia ceramics to dentin., Methods: Blocks of sintered zirconia ceramics were cut and randomly divided into 4 groups,16 slices in each group. Each group was subject to one of the 4 kinds of surface treatment (control group, sandblasting, sandblasting +silicone, sandblasting + silica coating + silicone) and then bonded to dentin with resin cement. After preservation in 37 degrees centigrade distilled water for 24 hours, the shear bonding strength of these specimens was tested and the data was analyzed with SAS6.12 software package for analysis of variance. The surface modality of the ceramics was observed under scanning electron microscopy (SEM)., Results: The group of sandblasting+ silica coating + silicone attained the highest shear bonding strength, which was significantly different from the other groups(P=0.000);There was no significant difference between the sandblasting and sandblasting + silicone group (P=0.827), which was significantly different from the control group(P=0.001)., Conclusion: Silica coating by sol-gel process, coupled with silicone, can significantly increase the bonding strength of zirconia ceramics to dentin.

Purpose: To study the bonding strength of zirconia ceramics with 4 kinds of luting cement materials., Methods: Blocks of sintered zirconia ceramics were cut and randomly divided into 4 groups with 16 slices in each group. They were treated with sandblasting and bonded with 4 kinds of luting cements respectively. After preserved in 37 degrees C distilled-water for 24 hours and 30 days, the shear bonding strength of these specimens was tested and the data were analyzed by SAS6.12 software package and bond section were observed by scanning electron microscope., Results: Two-way ANOVA revealed that the group of PanaviaF could attain the highest shear bonding strength: (34.7+/-3.44) MPa (after 24 hours), (31.5+/-3.44) MPa (after 1 month), which was significantly different from other treatment methods (P<0.01). The initial shear bonding strength of the groups of resin-reinforced glass ionomer was (15.5+/-2.71) MPa, (16.0+/-1.77) MPa (after 24 hours) but dropped markedly to (6.80+/-1.24) MPa, (3.38+/-2.32) MPa after 30 days (P<0.05)., Conclusions: Resin luting cement containing phosphate monomer (MDP) can provide zirconia ceramics a strong and long-lasting bonding. Resin-reinforced glass ionomer can get good bonding strength too, but can't last long.

Purpose: To study the influence on the abutment movement with three kinds of precision attachments designed for distal-extension removable partial dentures (RPDs)., Methods: Snap attachment, Ceka attachment, Mini-SG attachment were used to retain RPDs. Then food chip was masticated between the upper and lower dentitions on the attachments side. Placement of abutment was measured by LB-72 high-sensitive-laser-traneferring-detector and the data were statistically analyzed for random block analysis of variance., Results: The displacement, inclination, and torsion of the abutment movements in the mesial-distal, bucco-lingual and occluso-gingival directions all had statistical significance (P<0.05). The largest mesial-distal inclination occurred with the Mini-SG attachment. The Ceka attachment produced more abutment displacement in mesial distal and apical directions. Occlusal displacement and anti-clockwise rotation were the least with the Snap attachment., Conclusion: The most equitable distribution of stresses on the supporting structures was achieved by Snap attachment with its resilent assemble, Ceka attachment transfers most of the loading forces to the abutments, Mini-SG attachment can not reduce the excessive torque applied to the abutments effectively.