Objective To investigate the effects of calcium phosphate/poly (lactic-co-glycolic acid) composite cement (CPC/PLGA) on expression of inflammation factors TNF-α, IL-1, IL-6 in osteoclast precursors, and to understand the mechanism of PLGA in promoting the degrading of CPC. Methods ① According to the concentration of lactic acid and glycolic acid detected by high performance liquid chromatography (HPLC) method, CPC/PLGA alternative solution was configurated. ② RAW264.7 cells were cultured in DMEM medium (control group), 6 h CPC clot soaking liquid (group A) and CPC/PLGA alternative liquid (group B).The proliferation of RAW264.7 cells were tested by CCK-8 method. Then the cells from each group were stimulated, and subsequently the mRNA expressions of TNF-α, IL-1, IL-6 were analyzed through RT-PCR. Results Proliferation assay revealed that the cell proliferation of group A reached its maximum which was 1.01±0.02 at 5 d, while group B at 5 d was 1.07±0.02, and compared to control group, the differences were statistically significant (P＜0.05); RT-PCR showed that TNF-α mRNA, IL-1mRNA expression in 6 h was highest in group A and group B, while IL-6 mRNA expression in 12 h was highest, and compared with the control group the differences were statistically significant (P＜0.05). Conclusion CPC/PLGA can increase the expression of inflammation factors in osteoclast precursors.

Objective To investigate the expression of transcription factor Brn3a and Isl-1 in trigeminal ganglion during the three periods of growth and development. Methods Mouse brains at 13.5, 15.5 and 17.5 days after being born were used for contrast. The immunofluorescence technique was applied to investigate the expression patterns of Brn3 and Isl-1 in trigeminal ganglion between different periods. Results In all three periods, Brn3a and Isl-1 were co-expressed in the trigeminal ganglia. In the early stage of growth and development, Isl-1 showed no significant proliferation, and in the late stage of growth and development, Brn3a showed no significant apoptosis. Conclusion In the late stage of development, Brn3a and Isl-1 marked neurons were still expressed in the neurons, and with the growth and development, the marked Brn3a and Isl-1 neurons gradually decreased. Besides, during the process of growth and development, Brn3a and Isl-1 marked neurons differentiated into subtypes of neurons, which regulated the upstream and downstream transcription factors.

Objective To investigate the effect of psychological stress on the healing process of experimental oral mucositis in rats. Methods 80 male rats (Sprague-Dawley) were randomly divided into four groups:5 rats in control group (Control), 75 rats in ulcer group (U), ulcer and stress group (U+S), and ulcer and stress + drug group (U+S+M), with 25 rats in each group. The rats with ulceration were euthanized at 0, 24, 48, 72, and 120 h (5 rats per experimental period). Psychological stress was induced by subjecting rats to restraint stress (6 h/d) for 7 consecutive days. Oral ulcer was induced by using a 4-mm tip monopolar electrode to cauterize in U, U+S, U+S+M groups. Then, psychological stress was given to the rats in both U+S and U+S+M groups at point-in-time continually. Also, diazepam was given to U+S+M group 1 mg/kg daily. The body weight gained，behavior tests and serum tests were used to testify stressed condition. Histological examinations were used to evaluate the changes of periodontal tissues and immunohistochemistry was used to evaluate the expression of HSP70. Results The stressed rats showed less body weight gained, abnormal behavioral changes and increased serum corticosterone (CORT)and adrenocorticotropic hormone (ACTH)( P＜0.05). The surface of inflammatory infiltrate of the stress group was significantly higher than other groups and the expression of hsp70 in control and ulcer group was lower than in stress group (P＜0.05). Conclusion Psychological stress can result in delayed healing process of the tissue in oral ulcer while diazepam might antagonize the stress and alleviate its negative effect．

Objective To extract and purify pomegranate peel polyphenols, and to study its effect on streptococcus mutans. Methods Resin adsorption method was used to purify ethanolic extract to polyphenols. The purity of pomegranate peel polyphenols was tested by Foline-phenol method. Broth dilution test was used to study the antibacterial effort of polyphenols and its effect on bacterial acidogenicity. Results The purity of pomegranate peel polyphenols was 82.03%. The minimal inhibitory concentration (MIC) was 0.5 μg/L and the minimal bactericidal concentration (MBC) was 1.0 g/L. With the increasing concentrations of polyphenols, the acidogenicity capacity of bacteria was decreasing. Conclusion Pomegranate peel polyphenols has a potential effect on antibacteria.

Objective To investigate the effect of shLRP5 on the osseointegration on SLA-treated titanium implant surface by constructing shLRP5 lentivirus vetor. Methods One target gene, LRP5, was testified to be involved in the SLA-treated-peri-implant bone formation. The implants were separated into two groups:LV-LRP5 group and blank group. Twenty implants were inserted into tibias of ten rats. We injected shLRP5 lentivirus vetor around implants of LV-LRP5 group. The effect of the SLA surface on peri-implant bone formation was evaluated by histomorphometric analysis. Bone to implant contact (BIC) and bone area (BA) were measured and statistically analyzed. Results LV-LRP5 transfected BMSCs stably. After 6 weeks of implantation, the implant bone contact rate and bone density in the LV-LRP5 group were lower than those in the blank group. Both two groups had significant difference (P＜0.05). Conclusion shLRP5 decreased the osseointegration on SLA-trated titanium implant. The mechanism of shLRP5 that decreased the osseointegration on SLA-trated titanium implant might be the decrease of Wnt/LRP5 pathway or cross talk with other pathways.

Objective To evaluate the effect of different power of Nd:YAG laser on the removal of root canal filling materials by measuring the removal percentage of root canal filling materials and the change of the temperature on the root surface. Methods 40 maxillary central incisors were prepared by ProTaper rotary files and filled by SybronEndo filling system. After that, 40 teeth were randomly divided into four groups of 10 each, namely experimental groups A, B, C and control group D. Root canal filling materials of four groups were removed by 1.0, 1.5, 2.0 W Nd:YAG laser and ProTaper D3 respectively, and temperature changes on the root surface were also measured at the same time. The Mimics software was used to process the data of CBCT before and after treatment. The removal percentage of root canal filling materials was calculated. Results The average removal percentage of filling materials in group A, B, C and D was 80.49%, 89.82%, 78.09%, 21.09%, respectively. There was significant difference within groups (P＜0.05), except for group A and C. Average temperature increase of group A, B, C and D were 5.28, 6.48, 7.73, 0.80 ℃, respectively, with significant differences between experimental groups and control group (P＜0.05). Conclusion Nd:YAG laser can effectively remove the root canal filling materials, the parameter of 20 Hz, 1.5 W, SP Nd:YAG laser (group B) has a high removal percentage, and the temperature increase on the root surface is within the tolerance range of periodontium.

Objective To engineer vascularized tissue with two types of cells from peripheral blood. Methods Endothelial progenitor cells (EPC) and peripheral blood-derived mesenchymal stem cells (PBMSC) were isolated from rabbit peripheral blood and identified. Then, they were cultured in fibrin at different ratios under the observation of a microscope until the 7th day after the initial creation. Results EPC and PBMSC were successfully isolated from rabbit peripheral blood. Vascularized tissue were acquired at a certain ratio (EPC were 1 million cells/mL, PBMSC were 2 million cells/mL). Conclusion Certain cells isolated from peripheral blood can be used to acquire vascularized tissue by co-cultured strategy at a certain density in vitro.

Objective To explore the differences of the membrane ductility of goat paranasal sinus membrane and analyze the reasons that may cause these differences and to provide theoretical basis and guidance for the issues of the maxillary sinus floor augmentation related to the membrane. Methods The membrane was cut into desired size from every sinus membrane. The ductility data were measured by using the push-pull gauge and the homemade fixtures. The results were analyzed by One-way AINOVA. Results Goat maxillary sinus membrane ductility of the top was (4.68±0.94)N, that of the bottom was (5.27±1.12)N, and the frontal sinus membrane was (1.97±0.46)N. The mean differences of membrane ductility between the top of the maxillary sinus and the frontal sinus, the bottom and the frontal were statistically significant (P＜0.05), while the top and the bottom were not statistically significant (P＞0.05). Conclusion The top and bottom membrane ductility of maxillary sinus is bigger than that of the frontal sinus membrane. There is no difference between the top and the bottom membrane ductility of maxillary sinus.

Objective To explore the dynamic change for micro-component and micro-morphology of implant-bone interface at early stage in hyperlipidemic rats. Methods Wistar rats were randomly divided into the experimental group and the control group. Rats of the experimental group were given a high-fat diet to create hyperlipidemia molding rats. After 12 weeks, titanium implants were planted into femora of hyperlipidemic and normal rats. The animals were sacrificed at 1, 3 and 5 days after implantation. Hard tissue sections containing micro-screws were made. The dynamic change for micro-component and micro-morphology of implant-bone interface at early stage were analyzed by energy dispersive X-ray spectrometer (EDS) and scanning electronic microscopy (SEM) respectively. Results There were fewer osteoblasts (P＜0.05) and more osteoclasts (P＜0.05) in the experimental group than in the control group. The ratio of Ca/P of the experimental group was lower than that in the control group (P＜0.05). The content of O in the experimental group was higher than that in the control group (P＜0.05). The content of Ti gradually reduced from implants to bone, and there were no significant differences between the experimental group and the control group. Conclusions The number of osteoblasts and Ca, P deposition of implant-bone interface at early stage in hyperlipidemic rats decreased, while the number of osteoclasts increased. Hyperlipidemia inhibits the early osseointegration of implants.

Objective To investigate the relationship between the expression of Axl gene and oncogenesis of oral squamous cell carcinoma (OSCC). Methods The immunohistochemical expressions of Axl genes in tumor tissues from 42 patients with OSCC (OSCC group) and in correspondingly adjacent tissues (adjacent group) were examined. In vitro, expression of mRNA and protein of Axl in normal human oral epithelium cell (HOEC), immortalized normal oral keratinocyte cell (NOK), tongue squamous cell carcinoma cell lines UM1 and UM2 were detected by real-time fluorescent quantitative polymerase chain reaction (qRT-PCR) and Western blot (WB), respectively. Results There was significant difference between OSCC group and adjacent group (61.9% vs. 26.2%, P＜0.05) in immunohistochemical expression of Axl. Expression of mRNA and proteins of Axl in UM2 and UM1 were significantly higher than those in HOEC and NOK in vitro. Conclusions Strongly expressed in OSCC tissue and cell lineages compared with their normal counterparts, Axl gene may play a role in OSCC oncogenesis.

Objective To determine both short-term and long-term effect of preheating on the microhardness of 4 composite resins. Methods 24 samples (5 mm diameter×2 mm height) of each of the 4 composite materials (Z250, Dyract, Tetric and SDR), were divided randomly into 3 groups (n=8 per group). These groups were cured respectively with curing light at 3 different temperatures (room temperature, pre-heated to 37 ℃, pre-heated to 55 ℃). After curing, microhardness of both top and bottom surfaces of each sample was measured by microhardness tester at moments, 24 hours later, 1 week later and 1 month later. Data were analyzed by SPSS. Results There was no significant difference in microhardness between top and bottom of the 3 composite resins at 3 different temperatures except Dyract. There was no significant difference in microhardness between the 4 composite resins at 3 different temperatures. With the time lapsing, the microhardness of the 4 composite resins gradually increased and finally tended to stability. Conclusion Preheating has no effect on microhardness of these 4 composite resins.

Objective To evaluate the effects of Er:YAG laser(EL) with different adhesive systems on the shear bond strength (SBS) of E-max CAD restoration in order to provide reference for clinical application of Er:YAG laser. Methods 80 newly extracted third molars prepared for SBS test and electron microscope analysis were randomly assigned to five groups. The buccal surface of each group was marked with ABCDE, and the lingual surface of each group was marked with abcde. Treatment method of each surface was as follows:A/a:EL+Optibond Versa/Adper Easy One; B/b:EL+35%phosphate etch+Optibond Solo Plus/Adper Single Bond 2; C/c:EL15.73 J/cm2/31.46 J/cm2; D/d:Optibond Versa/Adper Easy One; E/e:35%phosphate etch+Optibond Solo Plus/ Adper Single Bond 2. Bond strength test:3.5 mm×2.0 mm E-max CAD on lays were placed onto resin cement and bonded with the specimens. Electron microscope analysis:The dentin-adhesive interfaces were evaluated for the ultra structure of hybrid layer. Data of SBS(MPa) were statistically analyzed by ANOVA and χ2 test. Results Dentin irradiated by Er:YAG laser combined with total-acid etching system demonstrated significantly higher SBS (P＜0.05) compared to other group (23.01±4.41/25.37±3.96)MPa. Conclusion Er:YAG laser irradiated tooth surface combined with total-acid etching adhesive of different manufacturers can effectively improve the shear bond strength of dentin and ceramic.

Objective To evaluate the in vitro cytotoxicity of phosphorus-magnesium whisker solutionto human embryo kidney 293cells, and to provide a reference for it in the potential clinical application in the fields of dental resin and bone scaffold et al. as intensive inorganic filler. Methods Phosphorus-magnesium whisker were diluted to 5 different concentrations:1 000, 500, 200, 100, and 50 μg/mL. The impact of each group of whisker on human embryo kidney 293 cell proliferation and cytotoxity level were assayed with MTT method. The results were statistically analyzed. Results ①High concentrations of phosphorus-magnesium whisker solution had cytotoxic effects on human embryo kidney 293 cells. As the concentration and the time increased, the cytotoxity increased. No obvious cytotoxic effects were observed at or below the final concentrations of 333 μg/mL. ②Merely at the 72 h, the cytotoxity grades of 1000 μg/mL whisker solution were level 2, the rest group were all level 1. Conclusion Phosphorus-magnesium whisker has good biocompatibility when its concentration is ≤333 μg/mL, which meets with the requirement for enhancing the property of dental resin and bone scaffoldas intensive inorganic filler.

Objective To study the color stability of prosthesis silicone elastomer covered by nano-TiO2 membrane caps coated by silica alumina at different thickness, and to explore the effectiveness of this method on improving the color stability of facial prostheses silicone rubber, as well as to provide a theoretical basis. Methods Using MDX4-4210 silicone elastomer as substrate, nano-TiO2 coated with Si and Al as masking agent, and cadmium red oil paint as coloring agent, L*a*b* values of nano-TiO2 membrane cap specimen coated by silica alumina at different thickness (0, 0.5, 1.0 mm) before and after aging were observed. Results 0.1% silica-alumina-coated nano-TiO2 membrane cap specimen ΔE, Δa gradually decreased as the thickness increased (P＜0.05), while ΔL, Δb gradually increased as thickness increased (P＜0.05). Conclusion Coating nano-TiO2 membrane caps with silica alumina at different thickness played a role in delaying the fading of prosthesis silicone elastomer, which provided inspiration for improving the color stability of silicone elastomer prosthesis.

Objective To observe clinical effects of Optibond Versa self-etch bonding in treating the enamel defect of anterior teeth. Methods 196 anterior teeth with enamel defect in 89 patients were randomly divided into Optibond Versa (group A), Optibond S (group B) and IBond (group C), and nanometer resin was bonded. The patients were followed up after six months and twelve months for checking the situation of the filling and dental pulp. Data were analyzed by χ2 test. Results After six months, the success rate of the restoration on the tangent angle and the cutting end of group A, group B and group C were 93.75%, 93.33%, 70.00%, respectively. The different success rates of group A and B had no statistically significance (P＞0.05). The different success rates of group C and group A, B were statistically significant (P＜0.05). The success rates of the restoration on the adjacent surface, lip and tongue of group A, group B and group C were not statistically significant (P＞0.05). After twelve months, the success rates of the restoration on the tangent angle and the cutting end of group A, group B and group C were 90.00%, 90.00%, 67.74%, respectively. The different success rates of group A and B were not statistically significant, the different success rates of group C and group A, B were statistically significant, and the success rates of the restoration on the adjacent surface, lip and tongue of group A, group B and group C were not statistically significant (P＞0.05). Conclusion Optibond Versa self-etch bonding can obtain better effect in treating the enamel defect of anterior teeth.

Objective To investigate the effects of Team- Based Learning (TBL) teaching model in periodontology. Methods 84 students were randomly divided into two groups. Students in control group were taught by the traditional teaching model and students in experimental group were taught in the TBL teaching model. The teaching effects were evaluated by questionnaires and scores. Results The score of experimental group was higher than that of control group (t=5.53, P＜0.05). According to the questionnaire, the evaluation of TBL teaching model was better than that of that traditional teaching model. Conclusion The TBL teaching model can improve the students' comprehensive ability to analyze and solve problems, so it applies to teaching of periodontology.

Objective To observe the clinical effect of immediate implant placement and instantly using provisional restorations on inducing gingival formation in the aesthetic area. Methods 45 patients whose single tooth in the maxillary anterior teeth was treated by immediate implant prosthesis were selected from March 2012 to September 2014. They were randomly divided into Group A, B, and C, 15 cases in each. Group A immediately used provisional restoration to induce gingival formation; Group B postponed using provisional restoration to induce gums; Group C installed only healing abutment as a transition, and made permanent crown restoration 3 months later. After completion of repair on the same day, 6th month and 12th months, aesthetic evaluations were made on soft tissue around the implant by the pink esthetic score (PES). A year later, the patient’s aesthetic satisfaction was investigated using visual analogue scale (VAS) method. Results During the period of tracking assessment, PES of group A, B, C on the day permanent repair was finished were(12.17±1.26), (11.69±1.08), (8.73±1.02), respectively. No obvious difference was found between A and B (P＞ 0.05), while significant differences were found between group A and C, and group B and C (P＜0.05). In addition, the patient’s satisfaction of group A (92.6%) was also significantly higher than group B and C (87.3%, 69.6%) during the follow-up a year later. Conclusion Immediate implant placement and instantly inducing gingival formation in aesthetic area is clinically feasible with reliable short-term effect of aesthetics, and high satisfaction from the patients, which also needs strictly fit the indications.

Root canal perforation and instrument separation are common complications of root canal therapy. With the development of micro-endodontic treatment, the repairing of root canal perforation has been more effective, and the broken instrument can be effectively removed. However, it’s still difficult to treat some patients by routine root canal therapy, and thus measures such as apicectomy and root amputation are needed to promote the healing of the periapical disease. This paper reported a modified amputation case with an encouraging short term prognosis.

Currently, light-cured composite resin has been extensively used in dentistry, and studies about the property of such materials are increasing. The resistance to wear of resin composite is an important factor that determines the clinical success. This article reviewed the wear mechanism of resin composite, laboratory wear test methods, and new fillers having been used to improve wear performance.

Bisphosphonates are commonly used to treat osteoporosis and bone-derived malignant tumors in clinic currently. But its complication osteonecrosis of the jaw always perplexes clinicians. Scholars from different countries have conducted a great number of researches on it. This paper gives a review of the latest research progress.

Developing defect of enamel (DDE) is the defect resulted from the disturbance in the formation and mineralization of hard tissue matrices during enamel development. Such defect can occur in infants and children in early childhood, and its adverse effects on structure and function of deciduous teeth have raised concern between clinicians and researchers. This paper reviewed epidemiological profiles home and abroad in the past 20 years on developing defect of enamel and its relations with early childhood caries.

In the daily life, people tend to focus more on positive smile, which is a reflection of personality, confidence and charm. Buccal corridor has received great attention as one evaluation index of facial aesthetics . This paper reviewed the research progress of the influence of buccal corridor on smile, and discussed how to create better smile aesthetics in orthodontic treatment by considering buccal corridor .