The study was design to investigate the clinical effect of Micro implant system in Italy on immediate mandibular implant-supported overdenture. A total of 192 patients with mandibular edentulous treated in our hospital were randomly divided into 2 groups in which the control group consisted of 96 patients treated with immediate mandibular implant-supported overdenture by Xive implant system, while the observation group included 96 cases treated with the overdenture by Italy Micro implant system. Patients were followed up for 1 year and then the states of implant-borne overdentures, marginal bone resorption around alveolar bone, the compatibility of implant restorations with adjacent teeth, adverse events and satisfaction degree were compared between the groups. According to the results of 1-year follow-up, the resorption around alveolar bone of the observation group was significantly higher than that of the control group (p<0.05). In the observation group the differences in labial gingival margin position, gingival color and texture were significantly better (p<0.05) as compared to control group. The incidence of adverse events was notably lower (p<0.05). The Italy Micro implant system has significant curative effect on mandibular implant-supported overdentures with good compatibility of the implant restorations with adjacent teeth and low incidence rate of adverse reactions, so it is worthy of clinical application and spreading.

目的:铸造基托结合排牙法应用于牙列缺损颌位记录中,并评价其临床效果.方法:将24例临床病例随机分成实验组和对照组,每组各12例.实验组采用铸造基托结合排牙法制取颌位记录,对照组采用蜡堤骀记录法制取颌位记录,并记录正中关系位准确率、颌位记录时间、初戴调合时间及咬合自如调合次数.结果:在正中关系位准确率上,实验组100％,对照组83.33％(P＞0.05);在颌位记录时间上,实验组5.5(4.25-6.75)min,对照组18.5(17.0-20.75)min(P＜0.001);在初戴调合时间上,实验组5.0(4.0-6.0)min,对照组10(8.25-13.0)min(P＜0.001);在咬合自如调合次数上,实验组1至4次分别为1(8.33％)、5(41.67％)、5(41.67％)、1(8.33％),对照组分别为0(0％)、2(16.67％)、7(58.33％)、3(25.00％)(P＞0.05).结论:铸造基托结合排牙法制取颌位记录准确、简便、减少临床椅旁时间,在临床上值得尝试.

Objective: To evaluate the effect of wireless biofeedback therapy on bruxism. Methods: Fifteen bruxiers participated to be treated by this therapy. The abnormal movements of teeth during sleep were monitored by a maxillary splint with an electric resistance strain gauge. Meanwhile, the receiver device recorded these details and analyzed the data, including the value of the biting force, occurring time and duration. If the value of biting force or duration exceeds the threshold, a vibrating device like a watch style will alert the patient to relax the masticatory muscles and nervous system to stop the abnormal grinding or clenching. Data were recorded during 8 hours’ sleep and analyzed after the 12 weeks’ treatment and 24 weeks’ treatment. Results: The average episodes of bruxism have declined from (10.60 ± 1.23) to (6.60 ± 0.75) after 12 weeks’ treatment (p p treatment, and the average duration of bruxism events was reduced to (3.37 ± 0.34) s (p

PURPOSETo observe the effect of gene therapy mediated by oral administration of attenuated Salmonella carrying tip30 and IFN-γ genes in human tongue carcinoma nude mouse model.METHODS25 four-week-old BALB/C male nude mice were divided randomly into 5 groups based on the differently harboring genes in the recombinant attenuated Salmonella typhimuriums SL7207, which included blank group (PBS), control group (SL7207), IFN treatments group (SL7207-pCI-IFN), tip30 treatment group (SL7207-pCI-tip30) and the combination of IFN and tip30 treatment group (SL7207-pCI-tip30/IFN). On 10d after submandibular subcutaneous injection of Tca8113 cells into the mice, the recombinant attenuated Salmonella typhimuriums were orally administrated 3 times at 1 week interval. The treatment effect indicators included the growth curve, the tumor inhabitation rate, the survival rate, the apoptosis typical DNA ladder and the protein expressions of tip30 and IFN-γ in tumor cells. Statistical analysis was performed with SPSS15.0 software package.RESULTSThe growth curve, the tumor inhabitation rate and the survival rate indicated that the tumor in the PBS group constantly grew up and induced the animal death in earlier time, while the SL7207 treatment had a slight inhibiting effect compared with PBS group. However, the SL7207-pCI-IFN group and the SL7207-pCI-tip30 had a moderate inhibiting effect compared with the SL7207 group, while the combination of IFN and tip30 had the strongest inhibiting effect. The protein expressions of tip30 and IFN-γ were detected in tumor cells while the typical DNA ladders of apoptosis were observed only in the tip30 gene transfer groups (SL7207-pCI-tip30 and SL7207-pCI-tip30/IFN).CONCLUSIONSThe recombinant attenuated Salmonella typhimurium possesses a capacity of gene transfer in vivo through oral administration. The combination of the harboring tip30 and IFN-γ genes have synergistic inhibiting tumor effect for tongue carcinoma.

目的 观察重组减毒鼠伤寒沙门菌作为基因载体在人涎腺腺样囊性癌裸鼠移植瘤中的富集情况和对外源基因的呈递能力.方法 以绿色荧光蛋白基因(GFP)为报告基因,以减毒鼠伤寒沙门菌SL7207为转基因载体,分别构建原核启动GFP表达的重组减毒鼠伤寒沙门菌SL7207-pUC-GFP和真核启动GFP表达的重组减毒鼠伤寒沙门菌SL7207-pEGFPN1.原核菌SL7207-pUC-GFP在体外连续传代,观察GFP基因表达的稳定性；同时,对荷人涎腺腺样囊性癌皮下移植瘤裸鼠模型口服给予原核菌SL7207-pUC-GFP(0.1 mL,1×109cfu/mL),在口服后24 h、48 h、5d、10d、20 d、30 d处死荷瘤裸鼠,获取肝、脾及肿瘤组织并制成匀浆液进行重组菌培养及GFP表达检测,观察重组菌在瘤体细胞内富集情况.对荷瘤裸鼠模型口服给予真核菌SL7207-pEGFP-N1,5d后取肝、脾及肿瘤组织进行冰冻组织切片,荧光显微镜下观察GFP的表达,了解重组菌携带外源基因在肿瘤细胞内的表达.结果 携带GFP原核表达的重组减毒鼠伤寒沙门菌SL7207-pUC-GFP在体外连续传代10次未见表达减少或缺失.荷瘤裸鼠口服原核表达GFP基因重组菌SL7207-pUC-GFP菌液实验表明,重组菌SL7207-pUC-GFP在肝、脾及肿瘤组织中能长期存活,以肿瘤组织中聚集明显(P＜0.05)且维持时间较长.荷瘤裸鼠口服真核表达GFP基因重组菌SL7207-pEGFP-N1菌液实验表明,相对肝脏和脾脏组织,外源基因在肿瘤细胞内表达量最高.结论 重组减毒鼠伤寒沙门菌可以在瘤体细胞内富集存活,并且携带的外源基因可以释放到肿瘤细胞内表达,具有作为基因治疗载体的双重优势.

PURPOSE:To explore the effectiveness of Osteopontin siRNA(OPNsiRNA) on viability and invasiveness of Tca 8113 by attenuated Salmonella typhimurium.METHODS: Synthesised OPNsiRNA and nonsense ControlsiRNA were separately constructed into expression vector pIRES2-EGFP,and were transferred into attenuated Salmonella SL7207.The tongue cancer cell line Tca 8113 was infected by the recombinant Salmonella SL7207,named SL-OPNsiRNA and SL-ControlsiRNA respectively.The infection rate,growth,apoptosis,migration and invasion were observed while the protein expressions of OPN,MMP-2 and uPA were detected by Western blot.SPSS15.0 software package was used for statistical analysis.RESULTS: The infection rates of the recombinant Salmonellas both were more than 80.0% without significant difference(P>0.05).The growth was significantly inhibited and the apoptosis was significantly induced after infection of SL-OPNsiRNA compared with SL-ControlsiRNA.After 24h-infection of SL-OPNsiRNA and SL-ControlsiRNA,the migration index was 0.56±0.10 and 0.82±0.05(n=12,P<0.01),the invasion index were 0.53±0.13and 0.83±0.06(n=12,P<0.01),respectively,and the intra-cell proteins of OPN,MMP-2 and uPA were also significantly down-regulated by OPNsiRNA compared with ControlsiRNA.CONCLUSIONS:OPNsiRNA could be effectively transferred into tongue cancer cells through attenuated Salmonella,and inhibited caner cell growth and metastasis.

Objective:To study the relationship between stracture and properties of a new type of dental machinable ceramic based on diatomite.Methods:By adding nanometer reinforcing agent,the new diatomite based dental machinable ceramic was fabricated.X-ray diffractometer(XRD) and scanning electron microscope(SEM) were used to characterize the crystal form and microstructure.The mechanical properties and the machinability of this new ceramic were evaluated.Results:The color of the ceramic after sintering was oyster white and its surface was smooth.SEM images presented polycrystalline structure and the grain edge was clear with decreased porosities.The flexure strength,microhardness and fracture toughness of the new ceramic reached 177.23±7.02MPa,9.73±0.64GPa and 3.93±0.58MPa·m1/2 respectively.The machinability of the material sintered at 700 degrees was good.Conclusion:The mechanical and esthetic properties of the new type of diatomite-based dental machinable ceramic were acceptable but the mechanical strength still needs to be enhanced.

OBJECTIVE To evaluate a new type of diatomite-based machinable ceramic biocompatibility by studying its induced apoptosis on L929 cell in contrasted with other prosthodontics materials. METHODS Cell line was treated with extracting liquid containing different concentrations of diatomite-based machinable ceramic and other materials. Flow cytometry tested cell cycle progression and induced cell apoptosis. Annexin V-FITC/PI apoptosis staining kit quantitative detected cell death patterns. The expression of Bcl-2 and Bax mRNA were determined by reverse transcription-polymerase chain reaction. RESULTS The experimental groups had no special influence on cell cycle. Apoptosis rates of the new ceramic closed to the negative group (P > 0.05). The apoptosis rate of resin was the highest, and the cell necrosis level of resin was increased, which had significant difference to the new ceramic (P < 0.05). The Bcl-2 and Bax mRNA levels of the new ceramic and the negative group were closed to each other, which had no statistical significance (P > 0.05). CONCLUSION The new diatomite-based machinable ceramic has no apparent cytotoxicity, which is consistent with the clinical application of the basic requirements of biocompatibility.

Objective To study the effects of sintering temperature on the properties and microstructures of diatomite-based dental ceramic.Methods Diatomite-based dental ceramic was prepared by dry press method and sintered at different temperatures from 600 ℃ to 950 ℃ at per 50 ℃.The physical properties and machinability were measured.Main phase and microstructure of the sintered blocks were tested.Results With the rising of sintering temperature,microhardness and fracture toughness of the diatomite-based ceramic increased.The best machinability of the ceramic appeared at the temperature of 750 ℃(P<0.05).Conclusions By controlling the sintering temperature,the properties of diatomite-based ceramic can be changed to fit the requirements of dental CAD/CAM all-ceramics.

Objective To identify the cytotoxicity of a new type of diatomite-based machinable ceramic and preliminarily evaluate its biocompatibility.Methods In the present study,we used MTT to assess the cytotoxicity of the new ceramic,comparing with other four prosthodontics materials.The cell lines(L929)were treated with extract dilutions of the prosthodontics materials for 1d,3d and 5d.In order to observe the changes in cell morphology,we observed absorbance(OD value)to calculate the relative cell proliferation rate(RGR),and determine the cytotoxicity grade.Results MTT method found no significant difference in the cell viability among control,new ceramic,pressable ceramic and Co-Cr alloy-porcelain(P>0.05).However,other groups were much higher than control(P<0.05).The cytotoxicity of all the materials was grade 1.Conclusion The new diatomite-based machinable ceramic had no apparent cytotoxicity to L929 cell.