Exposure of gingival margin is frequently observed in anterior teeth aesthetic restoration. How to obtain an expected result is a significant challenge during prosthodontic treatment. The present article discussed gingival biotype, conditions of periodontal tissue, location of margin of restoration, gingival retraction, and provisional restoration, etc. which would affect the final aesthetic outcome of anterior teeth restorations. The aim of this article is to figure out how to effectively avoid the exposure of gingival margin in anterior teeth aesthetic restoration, and to improve the finally aesthetic outcome of anterior teeth restoration.

Objective To explore the feasibility of using laser fluorescence device for assessing caries removal in primary teeth in vitro. Methods 8 primary molars with approximal caries were collected, and caries were removed in vitro. The laser fluorescence readings of dentin before and after caries removal were recorded. To judge the degree of caries removal by caries detector, polarizing microscope and dental microhardness tester. The correlation of DIAGNOdent reading with Viker’s Hardness was analyzed. The feasibility of using laser fluorescence for assessing caries removal was explored. Results The average Viker’s Hardness of dentin after caries removal with staining was （46.99± 12.44）HV, and the average Viker’s Hardness of normal control was（67.39±16.59）HV. There was significant difference between the two groups（P<0.05）. There was no significant difference between laser fluorescence readings before and after caries removal with staining（P>0.05）. And there was significant difference between the laser fluorescence readings before and after the caries removal without staining （P<0.05）. It was observed by polarizing microscope that there was no caries residue in sample, no matter stain or not. Conclusion The laser fluorescence could not distinguish stained dentin from caries, and is not suitable for assessing caries removal.

Objective To evaluate the coronal microleakage of teeth restored with fiber posts and composite cores with four different resin bonding systems. Methods Sixty extracted human maxillary single-rooted teeth were endodontically treated and randomly divided into four groups. Post spaces were prepared in the root canals. Four different resin bonding systems（RelyX Unicem, Dulink, DC core Automix, Luxacore）were used respectively to bond fiber posts and reconstruct cores. The specimens were immersed in India ink for one week. Subsequently all teeth were demineralized, dehydrated and rendered transparent. Then microleakage was observed with stereomicroscope. Results The microleakage degrees among four resin bonding systems were significantly different（P=0.007）, and group C showed the least microleakage compared with the other three. Conclusion Self-etching resin bonding systems have a super margin sealing ability.

Objective To establish three-dimension finite element model of mandible with two kinds of Replace implant, and to study stress of implant and abutment. Methods The data of components of the dental implant was measured, cross section of the mandible was scanned by spiral CT and image reconstruction technique was conducted. Threedimension finite element analysis software UG and MSC. Marc/Mentat were used to built the conjunction model and bone model of two implant systems. Axial loading（200 N） and 30° oblique loading（100 N）were applied on the models respectively, the stress distribution patterns of the implant and abutment of two implant systems were analyzed. Results The peak stress district was concentrated on the structure of the implant cervix, which was more obviously displayed on the Replace Select implant. The peak stress of oblique loading was higher than that of axial loading. The peak stress on the implant cervix of Replace Select implant was higher than that of Replace External Hex implant in all loadings. Conclusion To Replace Select especially, oblique force should be avoided on clinical practice in case of the implant fracture.

Objective To study the influence of the quorum sensing inhibitor brominated furanone on Porphyromonas gingivalis（P.gingivalis） biofilm formation. Methods Doubling dilution method was used to determine the minimal inhibition concentration（MIC） of brominated furanone on P.gingivalis. Absolute ethyl alcohol added in P.gingivalis bacterial suspension was used as the negative control, while P.gingivalis bacterial suspension as blank control. The influences of 1/4MIC, 1/2MIC, MIC, 2MIC of brominated furanone on P.gingivalis biofilm formation were studied by the optical density determination and scanning electron microscope（SEM）. Results Four groups of brominated furanone with different concentrations were shown to inhibit P.gingivalis biofilm formation. With the increased concentration of brominated furanone, optical density of P.gingivalis suspension decreased. The biofilm structures of 1/4MIC group, 1/2MIC group and MIC group were loose. Only scattered P.gingivalis cells but no biofilm structure was seen in 2MIC group. Conclusion Brominated furanone could inhibit P.gingivalis biofilm formation without the influence on bacterial growth. The future application of this chemical compound may provide a new possibility for the antimicrobial treatment of periodontal disease.

Objective To test the effects of different surface treatments on the adhesive strength between POPO fiber post and resin cement. Methods 50 fiber posts were divided into 5 groups at random according to different surface treatments. Group A: Control group, no treatment. Group B: Silanization for 60 s. Group C: Etching for 30 s. Group D: Etching for 60 s. Group E: Etching for 120 s. Crowns of 45 fresh premolars were removed and assigned randomly to 5 test groups. After bonding and embedding the retentive force of the samples were tested by an universal testing machine. The morphology of the post surface was observed by a scanning electron microscope（SEM）. Results There were significant differences among the effects of different surface treatments on the adhesive strength between POPO fiber post and resin cement（P<0.05）. Group D showed the highest adhesivestrength（207.33±7.58）N. There was significant different between group D and E（P=0.027）, but there was not significant difference between group D and C（P= 0.112）. Significant changes of post surface after different treatments were discovered by SEM. Surface roughness and area of fiber exposure increased. Conclusion The adhesive strengths have been enhanced after conducting different surface treatments on the fiber posts.

Objective To investigate the effect of different inner metal materials of porcelain-fused-to-metal（PFM） crown on periodontal tissue by means of measuring the level of soluble intercellular adhesion molecule-1（sICAM-1） and interleukin-1β（IL-1β） in gingival crevicular fluid（GCF） after PFM restorations. Methods 30 teeth were divided into three groups（Ni-Cr alloy group, Co-Cr alloy group and Au-Pt alloy group, 10 teeth each group）, and restored by Ni-Cr alloy, Co-Cr alloy and Au-Pt alloy PFM crown according grouping. At the point of pre-restoration, 6-month and 12- month after cementation, the clinical parameters including plaque index（PLI）, gingival index（GI） and gingival crevice depth（GCD） were detected, and GCF was collected from labial and lingual of mesial site and distal site. The level of sICAM-1 and IL-1β were detected. Results At the point of 6-month and 12-month after cementation, Ni-Cr alloy group showed significant difference for GI, GCD and all GCF indexes when compared to pre-restoration, Co-Cr alloy group and Au-Pt alloy group（P＜0.05）. At the point of 12-month after cementation, Co-Cr alloy group showed significant difference for GI, GCD and all GCF indexes when compared to pre-restoration and Au-Pt alloy group（P＜0.05）. All indexes have no significant difference for Au-Pt alloy group during the 12-month experiment times when compared to pre-restoration（P＞0.05）. Conclusion Non-noble metal has bad effect on the periodontal tissue.

Objective The aim of this study was to investigate the korrosionsneigung of three metal specimens for casing removable denture by means of electrochemical method. Methods Three kinds of test specimens were prepared, including cobalt-chromium alloy, nickel-chrome alloy with titanium and pure titanium. Then they were analyzed via linear polarization in artificial saliva simulating oral environment. From this electrochemical test the polarization curves of these kinds of specimens were recorded. Then the scanning electron microscope（SEM） and X-ray diffractometer （XRD） were applied to assess the morphology and phase changes before and after electrochemical corrosion. Results No typical Tafel curve had been recorded for pure titanium, other than cobalt-chromium alloy and nickel-chrome alloy with titanium. Nickel-chrome alloy with titanium got more negative corrosion potential and higher corrosion current than cobalt-chromium alloy. Via SEM, the obvious changes were observed on the morphology and phase before and after corrosion on cobalt-chromium and nickel-chrome alloy with titanium specimens while pure titanium having no change. The XRD provided us little changes on these all three materials. Conclusion The results confirm that the korrosionsneigung of the studied cobalt-chromium alloy in artificial saliva is lower than that nickel-chrome alloy with titanium. Pure titanium is the most stable one of the three materials and is extreme hard to be etched.

Objective To study the electrochemical corrosion behavior of Co-Cr, Ni-Cr and Ni-Cr-Be based porcelain alloys in NaCl solution. Methods Five samples of each alloy were made respectively, electric polarization curve of each alloy was obtained using potentiodynamic polarization technique. Self-corrosion potential（Ecorr ） , self-corrosion current density（Icorr ） , passive region and transpassivation potential were tested. Microstructure and constituent was examined using scanning electron microscopy and energy dispersive spectroscopy. Results Co-Cr alloy possessed the most desirable corrosion resistance because of its integrated, homogeneous and compact passive film. The poor compactness of Ni-Cr alloy’s passive film decreased its corrosion resistance. Ni-Cr-Be alloy exhibited the worst corrosion resistance due to the Cr and Mo depleted Ni-Be eutectic phases in the alloy. Conclusion Taking biological security into consideration, it is necessary to avoid the application of porcelain alloys with Be element. Co-Cr alloy with better biocompatibility possesses much broader prospect in the field of dental restoration.

Objective To assess the efficacy and safety of hyaluronate sodium（HS） for internal derangement of temporomandibular joint by means of systematic review on relevant randomized controlled trials. Methods After identifing the study question of the efficacy and safety of HS for internal derangement of temporomandibular joint, Medline, Cochrane Controlled Trials Register, EMBASE, OPEN SIGLE and CBM were searched electronically till October 3rd 2010. Hand -searching covering 19 dental journals in Chinese were also performed. Risk of bias assessment, with Cochrane Collaboration’s tool, and data extraction of included studies were conducted by two reviewers in duplicate. Meta analysis was done with Revman 5.0.23 and the quality of evidence was evaluated by GRADE. Results 10 randomized controlled trials met the eligibility criteria and were included. All these studies had unclear risk of bias. When compared with negative control, HS showed a significant advantage on maximal mouth opening in short and long term（P<0.05）, and clinical overall assessment in short term（P<0.05）, but its effect on pain control and long term effect on clinical overall assessment had no extra benefit（P>0.05）. Additionally, when compared with glucocorticoids, the participants who received HS injection would get a better clinical overall assessment in short term and less adverse drug reactions（P<0.05）, but presented a similar temporomandibular joint pain relief and maximal mouth opening （P>0.05）. Conclusion To a certain extent, HS had good efficacy and better safety than controls when treating internal derangement of temporomandibular joint. However, as the quality of some included studies were limited, more randomized controlled trials are needed to reinforce the conclusion.

Objective To explore the incidence, influence factors and treatment methods of oral mucositis（OM）following hematopoietic stem cells transplantation（HSCT）. Methods A clinical analysis about the total 71 OM cases occurring after HSCT among 166 patients in Peking University People’s Hospital during 2009 was completed. Results The healing rate of OM was 95.77% and the average healing time was（17.61±8.36）d after HSCT. There were no obvious effects of gender, age, HLA matches, conditioning regimen to the healing time of OM（P>0.05）. Conclusion Gender, age, HLA matches and conditioning regimen have no obvious effects on healing time. By given timely and effective treatment, the incidence of OM can be reduced and even severe OM can also be well cured.

The Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing 210029, China）  [Abstract] Objective To study the effects of two different endodontic sealers on the bond strength of two fiber posts cemented with adhesive resin cement. Methods Twenty-eight crownless human maxillary central incisors were prepared with the step-back technique and randomly divided into four groups according endodontic sealer and fiber: Group A, Cortisomol sealer+Matchpost fiber post; Group B, Cortisomol sealer+Macrolock fiber post; Group C, Guttaflow sealer+Matchpost fiber post; Group D, Guttaflow sealer+Macrolock fiber post. One week after fiber posts were bonded, a thin-slice push-out test was performed in a universal machine. Morphologic structure of the root canal dentin surfaces etched and the adhesive interfaces were examined by scanning electron microscopy（SEM）. Results The bond strengths of 4 groups were （7.06±3.22）, （9.31±3.61）, （6.90±3.13）, （9.71±3.42）MPa. The bond strengths of group B and D were significantly higher than that of group A and C（P<0.05）. There was no significant difference between group A and C, group B and D（P>0.05）. The cervical third had the highest mean push-out bond strength, next to middle third and apical third（P<0.01）. SEM showed that larger numbers of the dentin tubules were open after the root canals were etched and penetration of resin tags into the dentinal tubules increased in the coronal root region when compared with the apical root region. Conclusion The shear bond strength doesn’t have relationship with endodontic sealers. The serration significantly increases the retention of fiber post. The bond strengths are different at the three root segment sites.

Objective To investigate the relationship between the uncooperative behaviors of first-visit-dental children and correlative factors that include children’s temperament, severe of dental caries and so on in order to help dentists to make personal dentistry therapy plan for each child to prevent and deal with children’s uncooperative behaviors. Methods From the pediatric dentistry clinic, 195 first-visit-dental children（aged 3-7 years） from Dec. 2007 to Dec. 2008 were randomly selected to accept dental examination and accepted corresponding treatment according to personal therapy plans. Children’s clinic behavior was valued during treatment. The parents were asked to complete NYLS temperament parents scale questionnaires for 3-7 years old children. Results Among the 195 children, there were 114（58.46%） had dental fear and anxiety（DFA） and 66（33.85%） had dental behavior management problem（DBMP）. As the children’s age increased, the incidence of DBMP decreased. There were no statistical relationship between genders and children’s DFA/DBMP. The children’s severity of dental caries was related to their dental behavior, the more serious the caries, the more incident the DFA/DBMP of children. There were no statistically significant differences for the DFA/DBMP of temperament type children. But the score of sensory threshold was higher in DFA children, while physiological rhythmicity was lower in DBMP, the differences were significant. Conclusion In order to reduce the incidence of DFA/DBMP, we should pay more attention to children with serious caries, and provide them individual behavior management for different ages and temperament.

Objective To analyze the characteristics of cases of maxillary complex injury, to sum up experiences and lessons in the clinical first aid process, to evaluate different treatment effects of maxillary complex fracture and investigate the reasons for the failure of the treatment process. Methods 152 cases with maxillary complex injury were analyzed retrospectively. Results 2 cases（1.32%） died during emergency treatment. The cure rate was 62.67%（94/ 150） in the 150 survival cases. The cure rate of closed fractures were better than open ones and surgical treatments than non-surgical ways（P<0.05）; the cure rate of surgical treatment in stage Ⅰwas higher than Ⅱ（P<0.01）. Conclusion For patients with complex injuries of maxillary, first aid failure is mainly due to bleeding or asphyxiation. Therapeutic efficacy is influenced by treatment time, surgical approach, type of treatment and so on. The key to success of treatment is dependent on the early firm internal fixation and the functional protection and restoration of injured organs or tissues.

Objective To evaluate methodological and reporting quality of the randomized controlled trials on cognitive- behavioral therapy（CBT） on temporomandibular disorders（TMD）. Methods The electronic databases of Medline via Ovid, EMBASE, Cochrane Central Register of Controlled Trial, CBM and CNKI, and five Chinese stomatological journals were included to collect randomized controlled trial（RCT） and quasi-RCT（qRCT） on CBT on TMD. Data were assessed using the quality assessment criteria recommended by the Cochrane Collaboration, and the reporting quality was assessed using the consolidated standards of reporting trials（CONSORT） checklist. Results 232 articles were collected by the search strategy, of which 5（3 RCTs and 2 qRCTs） met the inclusion criteria. The methodological quality varied among the studies with 2 scored as B and 3 as C. The highest score evaluated by the CONSORT checklist was 24. Conclusion The methodological qualities of included studies on CBT on TMD are generally low, and its reporting quality which is checked by CONSORT is also unsatisfactory yet.

Objective To determine the feasibility of water fluoridation to prevent caries in Kunming by investigating the epidemiological status of dental caries and dental fluorosis of children, and to provide the longitudinal reference data for the long-term epidemiology survey of dental caries and dental fluorosis in Kunming city． Methods Through stratified cluster sampling method, 212 5-year-old children and 1 149 12-year-old children were recruited in the survey. Dental caries condition of each child was clinically examined, dental fluorosis was examined in 12-year-old group. Results The prevalence of dental caries of primary teeth in 5-year-old group was 73.6％, mean value was 4.47± 4.39. The values of permanent teeth in 12-year-old group were 53.5％ and 1.42±1.83． The prevalence of dental fluorosis in 12-year-old group was 4.1% and the average community fluorosis index was 0.03. Conclusion Based on the high prevalence of dental caries and the low prevalence of dental fluorosis, it is suggested that using water fluoridation to prevent caries is feasible and necessary in Kunming city.

Objective To find out the morphological regularity of root canal in the primary tooth． Methods Through transparent specimen of a set of deciduous teeth，the shape of root canal was observed under stereomicroscope． Results Among the deciduous anterior teeth, 92% were single canal except for one single-double mixed canal. Maxillary deciduous molar had 3 canals and mandibular deciduous molar had 4 canals, lateral canal and anastomosis between the root canals were popular in deciduous molar. Conclusion Deciduous root canal morphology is simple in anterior teeth and comparatively complex in molar．

Objective To compare the proteomic profiles of whole unstimulated saliva（WUS） of subjects with chronic periodontitis（CP） with that of healthy volunteers, and to identify proteins. Methods WUS was obtained from five subjects with CP and five healthy subjects, and proteins were separated using two-dimensional gel electrophoresis（2-DE）. Proteins, the level of which was significantly different among the two groups, were identified by computer image analyses and subsequent matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry（MALDI-TOF-TOF MS）. Results Seventeen differentially expressed points in the 2-DE gel between the two samples were found by professional software. And protein types of thirteen points were then identified. Among them, the point 737, 725, 692, 986 was the same protein, as well as the point 716, 535. They were respectively serum albumin; β-fibrin; chain B, human serum transferrin, recombinant N-terminal lobe, Apo form, crystal form 2; Ig alpha-1 chain C region; the GA module complexed with human serum albumin（HAB-GA）; chain B, crystal structure of a Rca-Rhogdi complexes; PRO2044; hypothetical protein; unnamed protein. Compared with whole saliva of healthy control subjects, the levels of them were increased in whole unstimulated saliva of CP subjects. Conclusion Comparison of the proteomic profiles of WUS of CP subjects with that of healthy control subjects reveals at least 9 differential proteins. The approach might be helpful to better understand to the etiology of CP.

Objective To investigate the influence of class Ⅲ forces in craniofacial morphology and sutural histology in Rhesus monkeys. Methods Six male Rhesus monkeys in mixed dentition were employed in this study, two as 90-day experimental group, two as 45-day experimental group and the other two as control respectively. The experimental monkeys were casted magnetic orthopedic appliance-Ⅲ（MOA-Ⅲ）, the control monkeys received no treatment. Intraoral photographs, casts and cephalometric radiographs of each animal were obtained at the beginning and at the end of the experiment. Fluorescent and haematoxylin-eosin staining were used to observe the histological changes in craniofacial sutures. Results In experimental groups, the maxillomandibular relationship changed more significantly in 90-day experimental group than 45-day experimental animals. But changes were scarcely noted in the control. The bony depositions of the sutures were distinctly found during the experimental period, especially in zygomaticomaxillary, transverse palatine, pterygopalatine and zygomaticotemporal sutures. Conclusion This study indicates that this kind of magnetic appliance could cause skeletal and dental changes of maxilla and mandible, and change the arrangement of connective tissues in craniofacial sutures, and lead to significant new bone deposition in craniofacial sutures.

Objective The aim of this study was to observe the change of bacterial adhesion on pure titanium coated with nitrogen-diamond like carbon（N-DLC） films and to guide the clinical application. Methods N-DLC was deposited on titanium using ion plating machine, TiN film, anodic oxide film and non-deposition were used as control, then made specimens adhering on the surface of resin denture base for 6 months. The adhesion of Saccharomyces albicans on the titanium surface was observed using scanning electron microscope, and the roughness was tested by roughness detector. Results The number of Saccharomyces albicans adhering on diamond-like carbon film was significantly less than on the other groups（P<0.05）, and the growth of bacterial cell was inhibited and in a poor state. The largest number of adhesion and cell strains grew well on anodic oxide film group and non-deposition control group. The change of surface roughness of N-DLC film was less than other group（P<0.05）. Conclusion Pure titanium coated with N-DLC film reduced the adhesion of Saccharomyces albicans after clinical application, thereby reduced the risk of denture stomatitis.

Objective To construct Dishevelled 2（Dvl2）-targeted siRNA plasmids and to identify the effective re- combinant plasmids in transciently-transfected RAW264.7 cells. Methods The interfering sequences of Dvl2 were de- signed according to the sequence of Dvl2 of GenBank. Five paires of oligonucleotides were synthesized and inserted into plasmid pMAGic 4.0 to generate siRNA expression vectors, which were identified by flora PCR and sequence analysis. The recombinant plasmids siRNA-Dvl2 was transciently transfected into RAW264.7 cells by Lipofectamine 2000, which was confirmed under a fluorescence microscope and the interfering efficiency was detected by real-time RT-PCR. Results Five Dvl2 siRNA frames were successfully inserted into the plasmid vector pMAGic 4.0, and the flora PCR and sequence analysis confirmed the correct construction. Three of the five siRNA vectors suppressed the expression of Dvl2 mRNA, in which the siRNA-Dvl2-3 was the most efficient. Conclusion The Dvl2-targeted recom- binant siRNA plasmids can be constructed successfully to inhibit Dvl2 mRNA expression in transciently-transfected RAW264.7 cells, which can be used to pack virus particles and to construct siRNA-Dvl2 stably-transfected RAW264.7 cells in further research.

Objective In order to make certain the compaction pressure as well as pre-sintering temperature on the machinability of the zirconia ceramic. Methods 3 mol nano-size 3 mol yttria partially stabilized zirconia（3Y-TZP） powder were compacted at different isostatic pressure and sintered at different temperature. The cylindrical surface was traversed using a hard metal tool. Surface and edge quality were checked visually using light stereo microscopy. Results Pre-sintering temperature had the obviously influence on the machinability of 3Y-TZP. The cutting surface was smooth, and the integrality of edge was better when the pre-sintering temperature was chosen between 800 ℃ to 900 ℃. Compaction pressure showed only a weak influence on machinability of 3Y-TZP blanks, but the higher compaction pressure result in the poor surface quality. Conclusion The best machinability of pre-sintered zirconia body was found for 800- 900 ℃ pre-sintering temperature, and 200-300 MPa compaction pressure.

Objective To study the sternocleidomastoid-clavicle myocutaneous flap（SCMCP） for repairing the compound operative defect after oral carcinoma resection, to observe its clinical effect, prognosis and advantages of SCMCP, and to develop a new operative method that implantation of dental implant can be performed simultaneously. Methods Sixteen patients underwent reconstruction with SCMCP after oral carcinoma resection and neck dissection during 2007 to 2009. Four of them（25.00%） underwent simultaneously implantation of dental implants in the clavicular flaps. Results None of these patients died postoperatively during the follow-up until now. One patient（6.25%） with buccal cancer encountered local recurrence resulting in reoperation, and the flap grows well up to now. A part of the skin paddle underwent necrosis in two patients（12.50%）, local fluidity was found in 2 patients（12.50%）, fracture of clavicle occurred during the operation in one patient（6.25%）. All the patients had good pronunciation and oral diet with no difficulty. Conclusion SCMCP is easy to survive, simple to perform, the clavicular figure and function won’t be destroyed significantly. SCMCP is a good operative method to repair the compound operative defect after oral carcinoma resection.

Objective To evaluate the potential role of BME-10X collagen/hydroxyapatite（HA） bone graft in periodontal tissue regeneration. Methods Four 18 months old male beagles in the experiment were treated with non-surgical periodontal therapy. At the sites of mandibular 3rd and 4th premolars at the time of dogs were treated with non-surgical periodontal therapy one week later, the teeth with the same name in the same jaw were selected to the experimental group（T group）or the control group（C group） at random. The defects in T group were filled with BME-10X collagen/HA bone graft while the defects in C group were filled with nothing. The dogs were sacrificed in twelve weeks and analyzed by histopathology. Results The defects in T group got more tissue regeneration compared with the defects in C group. The height of new bone（NB）was（3.01±0.14）mm in T group versus（1.32±0.11）mm in C group（P<0.05）. The height of new periodontal ligament（NP）was（3.12±0.19）mm in T group versus（1.35±0.12）mm in C group（P<0.05）. The height of new cementum（NC） was（3.30±0.15）mm in T group versus（2.70±0.12）mm in C group（P>0.05）. The new tissue guided by the bone graft was the same as the normal tissue in histopathology analysis. Conclusion The results of the study suggest that BME-10X collagen/HA bone graft is a good bone graft for periodontal tissue regeneration.

Objective To investigate the morphology and proliferation effects of adenovirus containing bone morphogenetic protein-2（BMP-2） on tongue cancer Tca8113 cells. Methods Tca8113 cells were transfected with the Ad- BMP-2 of 0, 50, 100 multiplicity of infection（MOI） respectively. Inverted fluorescence microscope was used to evaluate the morphological changes of these cells. Western blot analysis was performed to determine the expression levels of BMP-2 in the transfected cells. Methyl thiazolyl tetrazolium（MTT） assay was performed to monitor the proliferative activity of the infected Tca8113 cells and then the growth curve was made. Results The transfection efficiency reached  the highest when the MOI was 100. Moreover, the expression of BMP-2 was detected in Tca8113 cells by Western blot. There were no obvious morphological changes of the Tca8113 cells before and after transfection. And the proliferation of  ransfected Tca8113 cells decreased compared with control. Conclusion Ad-BMP-2 gene can inhibit the proliferation of Tca8113 cells in vitro.

Objective To evaluation the influences of lateral occlusal forces to stress distribution in filling material after the restorative therapy of wedge-shaped defect. Methods A three-dimensional finite element model of maxillary first premolar with wedge-shaped defect was established. The defect zone of the model with simulated glass ionomer was restored. Loads of different directions were applied on the model and stress analysis of restorative material were conducted. Results When the loading direction was parallel to the tooth long axis, restorative material unit subjected to relative small stress. When the loading direction was vertical to the cusp inclined plane, stress endured by restorative material unit was significantly increased, as the angle of loading inclination increased, the increase of stress became more pronounced. Conclusion After the restorative treatment of wedge-shaped defects in clinical, occlusal adjustment should be applied to reduce the inclination of cusp to relieve the lateral forces subjected by tooth so as to ease the stress burden of restorative material.

Objective To explore the correlation between expression of mitogen-activated protein kinase kinase 4  （MKK4） and metastasis of oral squamous cell carcinoma（OSCC）. Methods Expression levels of MKK4 mRNA and protein were examined in surgically resected oral squamous cell carcinoma specimens and corresponding lymph nodes by semi-quantitative reverse Transcription-polymerase chain reaction（RT-PCR） and immunohistochemistry. Results The expression of MKK4 in 48 cases of metastasis of lymph node group was significantly higher than 27 cases of without metastasis of lymph node group in 75 cases of paraffin-embedded OSCC samples（P<0.05）. The expression of MKK4 in 48 cases of metastatic lymph node lesions was higher than 48 cases of primary site of OSCC（P<0.05）. There was no correlation between the expression of MKK4 and primary site, size of tumor, histological grade（P>0.05）. The expression of MKK4 mRNA in 16 cases of metastasis of lymph node group was significantly higher than 22 cases of without metastasis of lymph node group in 38 cases of fresh OSCC samples（P<0.01）. The expression of MKK4 in 6 cases of matched metastatic lymph node lesions was higher than 16 cases of primary tumour（P<0.05）. Conclusion The upregulation of MKK4 protein and mRNA may be related with the invasion and metastasis of OSCC. MKK4 maybe played a promoting role in the progression and metastasis of OSCC.

A case of ectodermal dysplasia syndrome was reported in this article. This case report and relevant literature of ectodermal dysplasia syndrome let us know the clinical symptom, etiology and effect factors of heredity of this disease.

A case of malignant inflammatory myofibroblastic tumor was reported. The relevant literatures were reviewed to discuss the clinical and pathologic characteristics, diagnosis and therapy of malignant inflammatory myofibroblastic tumor.