Objective To observe the effects of endotoxin tolerance triggered by repeated stimulation of lipopolysaccharide (LPS) on TNF-α and IL-8 expressions in co-cultures of neutrophils and THP-1 cells. Methods Co-cultures of neutrophils and THP-1cells were pretreated with 1 μg/mL Porphyromonas gingivalis(P.gingivalis) LPS or 1 μg/mL Escherichia coli(E.coli) LPS for 24 h, washed and stimulated by the same LPS again for another 24 h. The levels of TNF-α and IL-8 in supernatants were detected by ELISA. Results The expression levels of TNF-α and IL-8 significantly increased in co-cultured cells stimulated by P.gingivalis LPS or E.coli LPS compared with those without any stimulation (P＜0.05). The expression levels of TNF-α in cells restimulated by P.gingivalis LPS or E.coli LPS were obviously down-regulated compared with those stimulated by the same LPS only once (P＜0.05), while the expression levels of IL-8 were significantly up-regulated in comparison with those secreted by co-cultures of neutrophils and THP-1 cells stimulated by the same LPS only once (P＜0.05). Conclusion Endotoxin tolerance may suppress the secretion of TNF-α and promote the production of IL-8 in co-cultures of neutrophils and THP-1 cells.

Objective To investigate the regulatory effects of microRN-A-223 on the expression of pro-inflammatory cytokines during the inflammation induced by P.g-LPS in GFs. Methods The expression of microRNA-223 in GFs was interfered by lentiviral transfection, then the optimum concentration of P.g-LPS (800 μg/L) was added to different GFs in which the expressions of microRNA-223 were over expression, suppression of expression and normal expression in vitro. The mRNA levels of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), interleukin-6(IL-6), and microRNA-223 were measured by qPCR, and the protein levels of TNF-α, IL-1β, and IL-6 were measured by ELISA. Results When P.g-LPS stimulated GFs to produce inflammatory response, the mRNA levels of microRNA-223 and the mRNA and protein levels of proinflammatory cytokines TNF-α, IL-1β, and IL-6 were significantly higher than those in normal cells. The mRNA and protein levels of proinflammatory cytokines increased with the up-regulation of intracellular microRNA- 223 (P<0.001), and the protein of IL-1β and TNF-α were restrained with the down-regulation of intracellular microRNA-223 (P<0.001). Conclusion When inflammation occurs in gingival fibroblasts, the expression of microRNA-223 increases and the pro-inflammatory cytokines IL-1β, TNF-α and IL-6 are up-regulated, further exacerbating inflammation in cells.

Objective To compare the stress distribution of endodontically treated premolar prepared with 3 different fiber post lengths and 2 different abutment heights, using finite element approaches. Methods A finite element model of the mandibular first premolar tooth defect was created, and 3 different fiber post lengths (11 mm, 14 mm and 17 mm) and 2 different abutment height (3 mm and 5 mm) were designed. A 100 N static load of 135° was applied on the buccal cusp of the mandibular first premolar to simulate occlusal force. The maximum compression and tension stress values were recorded respectively. Results The maximum tensile stress (16.47 MPa) and maximum compressive stress (-20.15 MPa) of the 11/5 combination were the highest; the maximum tensile stress (14.56 MPa) and the maximum compressive stress (-15.94 MPa) of the 17/3 combination were the lowest. The maximum tensile stresses of the 14 mm and 17 mm post length groups were lower than that in the 11 mm post length group. The maximum tensile stress and the maximum compressive stress concentration of the 3 mm abutment height groups were lower than those of the 5 mm abutment height group. Conclusion The finite element analysis results show that the fiber post length has a negative correlation, while the abutment height has a positive correlation with the maximum tensile stress and the maximum compressive stress in the cervical region.

Objective To investigate the influence of Arg-Gly-Asp tripeptide complex connected zirconia on the adhesion， proliferation and mineralization of osteoblast. Methods Plasma spray was employed to prepare zirconia coating on titanium plate, after hydroxylation and silanization, Arg-Gly-Asp tripeptide complex was connected on zirconia coating. The focal adhesion of osteoblasts was observed by confocal microscopy and the stained cell nucleus were counted to evaluate the proliferative ability of osteoblasts. Alkaline phosphatase and osteocalcin were measured to evaluate the mineralization of osteoblast by western blot. Results Osteoblasts on Arg-Gly-Asp tripeptide complex connected zirconia presented more focal adhesion and excellent proliferative ability. The levels of alkaline phosphatase and osteocalcin were higher in Arg-Gly-Asp connected zirconia than those of regular zirconia. Conclusion Arg-Gly-Asp tripeptide complex connected bio-active zirconia can promote the adhesion, proliferation and osteogenic mineralization of osteoblast.

Objective To reveal the role of lateral pterygoid muscle in traumatic temporomandibular joint (TMJ) ankylosis. Methods Bilateral TMJ complex trauma was performed in eight 6-month-old male sheep. Then, function of the right and left lateral pterygoid muscles was maintained (control group) or blocked (test group), respectively. At the end of the 12th week after operation, all the animals were sacrificed and TMJ complex samples were evaluated by gross observation, spiral computed tomography (CT) scanning, Micro-CT scanning and histological examinations. Results Gross observation revealed bony ankylosis in the control group while fibrous adhesions in the test group. Results of spiral CT and Micro-CT demonstrated that the control group showed calcified callus formation in the joint space and roughened articular surfaces after new bone formation, which protruded into the joint space. The maximum anteroposterior and mediolateral condylar diameters were significantly larger in the control group than those in the test group. Micro-CT also showed that the primary growth orientation of new trabeculae was consistent with the direction of lateral pterygoid traction in the control group. Furthermore, histological examination showed fibro-osseous ankylosis in the control group. However, these characteristics were not found in the test group. Conclusion The lateral pterygoid muscle plays an important role, which is similar to distraction osteogenesis, in traumatic TMJ ankylosis.

Objective The combination of phosphate ester monomers PENTA (Dipentaerythritol penta-acrylate phosphate) and dental Y-TZP (Yttria-stabilized tetragonal zirconia polycrystals) was proved by chemical method to explain why PENTA was able to enhance the bonding affinity between resin and zirconia. Methods 5%, 10%, 15%, 20% experimental PENTA primers were prepared and then conditioned with Y-TZP powders. Powders were washed repeatedly by acetone to wipe off the dissociative component and tested by FTIR (fourier transform infrared spectroscopy) and TG (thermogravimetric analysis). FTIR analysis focused on the changes between 10% PENTA in acetone solvent and the powders conditioned with different experimental primers. Peak fitting was carried out according to second derivations and the residual. The Y-TZP powder without primers was set as the control group in TG test. Result Two different peak fitting methods both indicated that the vibration of the P-O bond went towards lower wavenumber after PENTA conditioned with Y-TZP powder. TG test showed that PENTA with higher concentration reacted with Y-TZP more completely. Conclusion The chemical reaction between PENTA and Y-TZP relies on the phosphate group.

Objective To investigate the profile of microRNA expression in mouse pre-osteoblast cell under cyclic stretch and to find the differences in microRNA which are related to TGF-β signaling pathway. Methods MC3T3-E1 cells were cultured in vitro. Normal cells were considered as controls and loading group cells loaded with 12% elongation for 3 hours, the differential expressed microRNA of MC3T3-E1 cell under mechanical strain conditions was screened by microRNA Microarray Technology, and then the Quantitative Real-time PCR was used to verify the differences associated with TGF-β signaling pathway, and bioinformatics was used to predict the target genes that may be regulated by it. Results Compared with the control group, 41 differentially expressed microRNAs were filtered in loading group, in which 20 were up-regulated and 21 were down-regulated(P values were less than 0.05 and the difference multiples were more than 1.5 times). The Quantitative Real-time PCR results showed that compared to the normal culture group, the expression level of miR-132-3p increased in loading group, consistent with the microarray results and there was significant difference (P<0.05). After software analysis, miR-132-3p target gene may be Smad2. Conclusion The expression profile of microRNA in osteoblast is significantly affected by cyclic stretch stress, these differences may influence the biological function of osteoblast by TGF-β signaling pathway or its related signal molecules.

Objective To make a preliminary evaluation of the adhesive properties and antibacterial properties of methyl methacrylate bound sixteen alkyl two-ammonium chloride (DMAE-CB) and amorphous calcium phosphate (NACP) binder. Methods DMAE-CB and NACP were added to the commercial dentin adhesive according to different proportions. According to the different proportions, the experiment was divided into 8 groups, the commercialization of binder as the control group. The dentin shear strength was tested by universal testing machine, and the bacteriostatic experiment was conducted, the antibacterial activity against Streptococus mutans of different groups after adhesion was studied. Results The shear strength of control group was （17.96±3.45）MPa, the experimental group were A：（19.25±2.80）MPa, B：（18.70±2.42）MPa, C：（18.47±2.73）MPa, D：（18.22±2.50）MPa，E：（17.29±4.54）MPa, F：（18.40±2.98）MPa, G：（18.13±4.39）MPa, through statistical analysis of P=0.993 (P>0.05) the shear strength of the experimental group and the control group the difference was statistically significant; the control group in the contact bacteriostatic test had antibacterial effect, the experimental group of antibacterial monomer addition 1% had significant antibacterial effects (P＜0.05), when the dosage is 3%, the antibacterial activity was further enhanced, but when the content is 4%, the antibacterial activity did not significantly increase. Conclusion After adding DMAE-CB and NACP, the adhesive has no influence on the bond strength and has good antibacterial properties.

Objective：To compare shear bond strength(SBS) of rebonded metal orthodontic brackets between three kinds of treatment methods．Method：80 extracted human premolars were selected and evenly divided into four groups. The brackets were bonded to the 80 premolars and were debonded with shear tests to record the SBS. Residual adhesives on the base mesh of the brackets were treated with three different methods. In group I, new brackets were reused. In group Ⅱ, Ⅲ, Ⅳ, the base mesh were dealt with sandblasting, burning or carbide bur grinding, respectively. The brackets were rebonded and shear tests were performed among different groups. Results: In group I and group Ⅱ,the SBS of the second bonding was very closed to the first bonding, there was no significant difference between the second bonding and the first bonding ( P > 0 .0 5 ), In group Ⅲ and group Ⅳ, the SBS of the second bonding was significantly lower than the first bonding ( P ＜ 0 .0 5 ). There was no significant difference of the SBS of the second bonding between group Ⅱ and group I（P＞0.05）， In group Ⅲ and group Ⅳ, the SBS of the second bonding was significantly lower than the SBS of the second bonding In group I ( P ＜ 0 .0 5 ). Conclusion: To obtain enough bonding strength, was suggested to remove residual adhesives from the base mesh of bracket, carbide bur grinding and burning should not be used.

Objective To measure noise made by prosthodontists on workdays and in normal operations, and analyze noise exposure of prosthodontists. Methods ①The noise of clinic on workday was measured from 9am-10am at the same location. ②In the case of only one operation working, the noise of normal operation was measured at 15 cm, 30 cm, 45 cm. Results ①Environment noise of prosthodontic clinic was 63.6-73.5 dB. ②In the case of only one operation working, noise declined when measuring distance increased. The difference between the groups was statistically significant. The intensity of noise did not harm the hearing system. Conclusion Although the intensity of noise did not harm prosthodontists' hearing system, the frequency of noise ,the harm to nervous and cardiovascular systems should be focused .It benefits noise protection when prosthodontists keep standard gesture .

Objective To evaluate the effects of diode laser on the treatment for chronic periodontitis patients with type 2 diabetes mellitus. Methods 960 sites from 40 periodontitis patients with type 2 diabetes were randomly divided into experiment group and control group. Patients in experiment group were treated with initial therapy and diode laser therapy, meanwhile, only initial therapy was performed for the patients in control group. Sulcus Bleeding Index (SBI), probing depth (PD), clinical attachment loss (CAL) and systemic indexes (hs-CRP, HbA1c, GLU) were recorded before treatment, 3 months and 6 months after treatment. Results For both groups, 3 months and 6 months after treatment, all the indexes were significantly lower than those before treatment（P＜0.05）. 3 months after the treatment, SBI, PD and all the systemic indexes in experiment group were significantly lower than those of control group（P＜0.05）. 6 months after the treatment, SBI, PD and HbA1c were significantly lower than those of control group（P＜0.05）. And the differences of AL, HbA1c, GLU between two groups were not significant（P＞0.05）. Conclusion Diode laser is an effective adjuvant treatment for periodontitis patients with type 2 diabetes, especially for the relief of inflammation and the glucose metabolism in short term.

Objective To investigate the changes of hemorheology in patients with oral submucous fibrosis, and to analyze the relationship between the potential factors such as smoking and blood lipid and hemorheology, to explore the role of hemorheology in the pathogenesis of OSF. Methods A total of 57 clinic patients linical and pathological diagnosis of middle OSF were the content of blood viscosity with different shear, plasma viscosity, hematocrit, erythrocyte aggregation index and rigidity index, serum triglyceride (TG) and cholesterol (TC), and the subgroup analysis was applied according to smoking or not , TG and TC content. Results Patients possessing low, medium, high shear viscosity and hematocrit in all 57 patients with OSF were 38 cases (66.7%), 33 cases (57.9%), 22 cases (38.6%) and 38 cases (66.7%) respectively, significantly higher than the control (P<0.01). Plasma viscosity, erythrocyte aggregation index and rigidity index were not abnormal, but they had significant difference compared with the controls (P<0.05). In the subgroup analysis of OSF, the low shear blood viscosity, plasma viscosity and hematocrit of smoking group were higher than non-smoking group.The medium shear viscosity, the high shear viscosity and hematocrit in TC Increased Group were higher than the TC Normal Group. The differences were statistically significant (P<0.05). Conclusion The blood viscosity of patients with OSF is high, and smoking and cholesterol can aggravate high blood viscosity state, suggesting that smoking cessation and low-fat diet combining with blood circulation drugs have certain guiding significance to alleviate the local microcirculatory disorders in OSF patients.

Objective To research the variation of Actinomycetes viscous （A.v） of two kinds of high biocompatibility crown materials in different periods before and after restoration among the elderlg. Methods A total of 60 clinic patients, who needed restoration treatment of the mandibular first molar were collected, and randomly divided into zirconium dioxide all-ceramic crown group and sliver-palladium alloy porclain group. The self control study was used, the one before tooth preparation was set as control group, the one after restoration in six months and twelve months as experimental group. And the subgingival plaque on the edge of the crown was collected, fluorescent quantitative polymerase chain reaction was adopted to have relative quantitative analysis of A.v of samples. Results Compared with those before restoration, the quantity of A.v in six and twelve months after restoration in the zirconium dioxide all-ceramic crown group had no statistital difference（P＞0.05）; the quantity of A.v in six and twelve months after restoration in the sliver-palladium alloy porclain crown group had statistical difference（P＜0.05). Conclusion The zirconium dioxide all-ceramic crown can better reduce the risk of dental caries.

Objective To study the feasibility of making temporary aesthetic templates with 3D printing, and to compare the marginal adaptation of the aesthetic templates made by DMG Luxatemp and self-curing resin. Methods According to the unified standard of tooth preparation, two units, four units and six units of tooth preparation were made for 3 standard models of maxillary resin teeth, and 26 models of plaster cast were made. 3D printing, DMG Luxatemp and self-curing resin were used to make 5 two-unit crowns,5 four-unit crowns and 5 six-unit crowns respectively. The gap value of each group was measured by the gap replication method of silicone rubber and magnified 40 times under the stereo microscope. SPSS20.0 statistical analysis software was used to analyze the experimental data. Results There was a significant difference between the 3D group, DMG Luxatemp group and the self-curing resin group in the value of the gap between two-unit crowns, four-unit crowns and six-unit crowns (P<0.05).The edge clearance values of 3D printing group were (78.02±0.65)， (78.04±0.66)and（78.48±0.65)μm.The edge clearance values of DMG Luxatemp group were (101.24±1.61)， (100.71±1.60)and（99.37±1.38)μm. The edge clearance values of self-curing resin group were (154.62±9.69)， (155.76±4.39)and（152.34±5.21)μm. The best marginal adaptation was the 3D group, followed by Luxatemp group, and the worst margianl adaptation was the self-curing group. However, there was no statistical difference in the gap value between the two-unit crowns, the four-unit crowns and the six-unit crowns in the same group. Conclusion The marginal adaptation of the temporary esthetic templates made by 3D printing is better than DMG Luxatemp and self-curing resin.

Objective To assess the experiment effects of blocking therapy combined with mecobalamin on the treatment for patients with primary trigeminal neuralgia. Methods From February 2013 to December 2015， 80 cases (36 males and 44 females，aged from 38 to 82) , diagnosed as primary trigeminal neuralgia , were locally blocked in the neural stem of pain areas , with solution of 2% lidocaine 1.0mL and mecobalamin 2.0 mg (a total of 3.0 mL) ，1 time a day and 7～10 times were one course of treatment in our hospital. Results Among the 80 cases,61 cases were cured,10 cases were improved and 9 cases were in remission after the treatment. No side effects was detected during the whole treatment. Conclusion The blocking therapy combined with mecobalamin is an effective method with wide indications and without side effects in the treatment for trigeminal neuralgia.

Objective To compare the efficiency of two methods of tooth extraction and the incidence of intraoperative and postoperative complications , as well as to provide basis for the new clinical therapies. Methods 132 cases were divided into two groups randomly, using surgaical impact air handpiece and traditional method respectively. The extraction time, intraoperative and postoperative complications of two groups were compared. Results The extraction time of experimental group was shorter than the control group and there was significant difference between the two groups（P＜0.05）. The incidences of root fracture, gingival laceration, and injury of temporomandibular joint of experimental group were lower than those in the control group, and the difference was statistically significant（P＜0.05）. There was no significant difference in the lingual bone plate fracture, tooth mobility, nurve injuries and tooth slip into fascial space in the two groups（P＞0.05）.The incidences of postoperative pain, limited mouth opening, postoperative swelling and dry socket in the experimental group were lower than those in the control group, and the difference was statistically significant （P＜0.05）. Conclusion The new method with surgical impact air handpiece can improve efficiency, as well as reduce the incidence of complications, and it's worth the clinical expansion.

Objective To explore the association between periodontitis and ischemic stroke. Methods The electronic search was conducted to find the issues focusing on the association between periodontitis and ischemic stroke in Medline (OVID, 1950- 2016), Pubmed, EMBASE (1984-2016), CBM (1978-2016), CNKI and VIP database. Hand search was applied to the Chinese and English journal. Two investigators individually selected included trials, evaluated the quality of them and collected data. Revman 5.3.3 was applied for Meta-analysis of the data. Results Eight trials met the inclusion criteria (4 English research and 4 Chinese research), including 1702 participants, 846 of them with ischemic stroke. The result of Meta-analysis showed that the patients with ischemic stroke were more likely to be with chronic periodontitis (OR=2.98，95% CI=［1.61,5.51］， P=0.0005), with poorer health of gum(OR=0.27，95% CI=［0.16,0.38］， P<0.00001) and more severe periodontitis(OR=1.55，95% CI=［0.66,2.43］， P=0.0006). The levels of C-reactive protein increased obviously(OR=5.34，95% CI=［4.75,5.93］， P<0.00001). Conclusion Periodontitis and ischemic stroke have a significant correlation.

Objective To investigate the prevalence of dental caries of 8-year-old urban pupils in Xiangfang District of Harbin, and compare it with the results in 2015 to explore the trend of dental caries. Methods A sample of 1915 8-year-old pupils（Grade Three） who were from 10 primary schools in towns of Xiangfang District of Harbin was drawn for general survey. The survey included the dental caries of primary and permanent teeth, the first permanent molar eruption and pit and fissure sealant on first molar. Results The caries prevalence rate of the students was 91.23％, among which the caries prevalence rate of students’ deciduous teeth was 88.36％, with a xdmft of 5.49, xdmfs of 10.21 and the percent of filled teeth was 31.95％.The caries prevalence rate of students’ permanent teeth was 41.67％(There was a significant difference between male and female).The xDMFT was 0.95 and the xDMFS was 0.96.The eruption rate of the first permanent molar was 98.08%.The closure rate was 63.71% and the retention rate of sealant was 84.50%.These values were higher than those of 2015. Conclusion In recent years, the prevalence rate of dental caries among primary school students aged 8 years old in Xiangfang District of Harbin has been on the rise . Public awareness of caries prevention should be raised.

Aesthetic implantation in anterior maxilla is the focus of oral implantation. It depends on sufficient amount of soft and hard tissue. Inflammation and trauma can lead to the lack of bone mass and keratinized gingiva atrophy so that satisfactory aesthetic effect of implanting repair cannot be obtained .This case used the guided bone regeneration with titanium mesh to restore bone defect in anterior maxilla, and used the platelet rich fibrin to promote soft tissue augmentation. Then the ideal aesthetic effect of implanting repair is achieved.

Dentin hypersensitivity is a common clinical problem in dental practice, which is characterized by brief, sharp pain in response to stimuli. It has a high morbidity rate and a low cure rate demonstrated by epidemiological studies. The laser in the treatment of dentin hypersensitivity has attracted lots of attention in recent years. The research progress of clinical effects of laser in treating dentin hypersensitivity and its underlying therapeutic mechanisms are summarized in this review.

Aggressive periodontitis (AgP) is a subgroup of periodontitis, with the rapid attachment of periodontal attachment and the rapid absorption of alveolar bone as the main feature. Because of the early onset and systematic factors, AgP is a periodontal disease that is critical to human health. The treatment of AgP has been actively exploring owing to its unpredictable therapeutic outcome and unstable therapeutic effect. In this article, the progress of AgP’s treatment in recent years is reviewed.

At present the clinical treatment of wedge-shaped defect is mainly restorative treatment while problems of filling material shedding, micro leakage, dentine hypersensitivity, secondary caries occurred easily. According to the problems above new technology and materials continuously appear. This paper provides a brief review of the research development of restorative treatment for wedge-shaped defect, and provides reference for dentists.