Craniofacial malformation was related to the shape and structure of the teeth, jaws and face. Assessment of craniofacial complex in three-dimensional（3D） has long been a focus for many researchers. At present, 3D imaging techniques could reconstruct the craniofacial soft tissue or hard tissue successfully. However, they couldn’t reflect the comprehensive structure of craniofacial complex. For the study of the craniofacial complex, combination of 3D imaging techniques provides a promising way toward optimum 3D imaging. The purpose of this study was to reconstruct the 3D images of craniofacial hard and soft tissue based on cephalograms and laser scanning, to found the 3D measurement and orthognathic simulation and forecast system, which may provide a new method for analyzing of craniofacial malformation, and for the quantity control and evaluation of treatment results in the orthodontic treatment, orthopedics and plastic operation.

Objective To investigate the expression pattern of FHL2, which is an intracellular signaling transcription molecule during mineralization in cultured human periodontal ligament cells（hPDLCs） in vitro. Methods hPDLCs were cultured in vitro. Test group was cultured with mineral induction media while control group without induction media. 0, 14, 28 days after culture, alizarin red staining was used to measure the mineral nodules formation. Immunocytochemistry was used to examine the expression of FHL2 protein 0 day and 14 days after mineral induction. Meanwhile, mRNA expression level of FHL2 was analyzed by reverse transcriptase-polymerase chain reaction（RT-PCR） on the 0, 14, 28 days after induction. Results 14 and 28 days after cultivation, mineral nodules formed and were stained positively with alizarin red staining in test group while no mineral nodule formed in control group. Immunocytochemical results indicated that hPDLCs in test group expressed FHL2 positively. According to RT-PCR results, 14 and 28 days after mineral induction, the expression levels of FHL2 both increased significantly when compared with 0 day（P<0.01）, and the expression level at 14 days was 1.4 folds of 0 day. Conclusion FHL2 protein is found to be involved in the in vitro mineralization of hPDLCs. FHL2 protein may play a role in the differentiation and mineralization of hPDLCs.

Objective To explore the expression of glucose transporter（GLUT）-1 and insulin receptor（IR） α1 in osteoblast obtained from diabetic rats’mandibles. Methods The expression of GLUT-1 and IR α1 of diabetic and control groups were measured by reverse transcription polymerase chain reaction, Western blot and immunohistochemistry stain. Results The mRNA expressions of GLUT-1 and IR α1 of diabetic group were significantly higher than control group（P<0.05）. The protein expressions of GLUT-1 and IR α1 were similar to the mRNA expressions. Conclusion Osteoblasts obtained from diabetic rats’mandibles keep the adaptation changes to hyperglycemia and hypoinsulinemia, which may contribute to their dysfunction.

Objective To investigate the correlation between Helicobacter pylori（H.pylori） colonization in the oral
cavity and gastrointestinal disease. Methods 173 patients with gastrointestinal disease were grouped according to age, gender, periodontal status and types of gastrointestinal disease. H.pylori were detected from saliva samples of all patients by in vitro cultur. The H.pylori-positive rates in different groups were statistically analysed. Results The H.pylori-positive rate in all patients was 40.46% and the difference between male and female showed significant（P<0.05）. The H.pylori-positive rate was 56.72% in the age range 45-64, which was significantly higher than two younger age groups（P<0.05）. The H.pylori-positive rate in patients with atrophic gastritis was 77.78%, of which the difference was significantly higher than superficial gastritis group and gastric and duodenal ulcer group respectively（P<0.05）. The H.pyloripositive rate in healthy periodontia group was 15.38%, while that in periodontitis group was 72.73%（P<0.05）. Conclusion H.pylori is a conditional pathogen. The H.pylori-positive rate from saliva is closely related to the types of gastrointestinal disease in patients, and it is correlated with the periodontal diseases as well. These findings suggest that the oral cavity with periodontal diseases is an ecological niche of H.pylori which might be an important cause for occurrence and re-occurrence of gastrointestinal disease.

Objective To detect and analyze two important genes, comE and luxS, in quorum sensing signal pathway from Streptococcus oralis（S.oralis）. Methods The total genomic DNA of S.oralis NH521（a clinically isolated strain） was firstly extracted. The comE and luxS genes were then amplified by polymerase chain reaction（PCR） and further sequenced. The obtained sequences were compared with related sequences in GenBank. Results Target bands of both comE and luxS genes were detected by electrophoresis. The obtained gene sequences were similar to the corresponding sequences from another S.oralis strain（luxS, 95.0%; comE, 99.6%）; however, comparing to gene sequences of another species Streptococcus mutans, comE was more divergent（12.7%） than luxS gene（74.1%）. Conclusion This study successfully amplified and sequenced comE and luxS genes from S.oralis NH521 strain. The luxS gene accumulated more mutations than comE gene did between two S.oralis strains, but comE gene is more divergent than luxS gene between two Streptococcus species.

Objective To study whether SiO2 films will influence the color of Ni-Cr metal ceramic restorations. Methods For the film plating experimental group, Sol-gel method was employed to apply SiO2 films to the surface of the Ni-Cr copings, while no coating was applied for the non-film-plating control group. Veneering porcelains were then applied subsequently, and a total of 12 B2-colored maxillary incisor metal ceramic crowns were fabricated with 6 crowns in each group. A ShadeEye Ncc computer-aided colorimeter was employed to measure the shade of the samples, as well as 6 B2（Vitapan classical vita color tabs） shade standards. The color was expressed as CIE-1976-Lab coordinates. Results There was a statistically significant color difference between all metal ceramic crowns and the B2 shade standards（ΔE>1.5）. The L*, a*, b* values of all crowns were higher than those of the B2 shade standards, and the crowns were typically yellower or redder. While neither significant color difference nor difference in shade values was observed between the film plating experimental group and non-film-plating control group（ΔE<1.5）. Conclusion SiO2 films applied to the Ni-Cr copings by means of Sol-gel technique do not impact the final color of the metal ceramic restorations.

Objective The residual dentin thickness of first premolars were measured by anatomical methods before and after post preparation, the data from which can help clinicians to choose proper sizes of peeso drill. Methods 30 first maxillary premolars and 30 first mandibular premolars were collected. Walls of 4mm short of the apex were respectively measured before and after post preparation with peeso drills number 1-3. Results The measurement results of all indexes assumed a normal distribution. For two-canal first maxillary premolars and single-canal first mandibular premolars, the average residual mesial and distal thickness of root walls 4 mm short of the apex were less than 1 mm after post preparation by number 3 peeso drill. The buccal root had nonsignificant differences（P>0.05）. The palatine root and the first mandibular premolars had significant differences（P<0.05）. For single-canal first maxillary premolars, the average residual mesial and distal thickness were less than 1 mm after post preparation by number 2 peeso drill. The distal wall had significant differences（P<0.05）. Conclusion In post preparation, for the buccal root of two-canal maxillary premolars, the maximum size of peeso drill was number 3, and for the palatine root and first mandibular premolars, the size was number 2, and for single-canal maxillary first premolars, the size was number 1.

Objective To examine and analyze the interleukin（IL）-1B gene single nucleotide polymorphism（SNP）at positions ＋3954, and explore the association between SNP and risk of chronic periodontitis（CP） among the Hui and Dongxiang minorities in Gansu province. Methods CP group consisted of 215 patients from Hui and Dongxiang and healthy control group consisted of 219 subjects. Anti-coagulated peripheral blood sample was obtained from each subject and genomic DNA was extracted from each sample. SNP at IL-1B+3954 were analyzed by standard polymerase chain reaction-restriction fragment length polymorphism（PCR-RFLP） assay. Results Statistically significant differences were found in genotype and allele frequencies between CP group and healthy control group. The exist of position alleles C increased the incidence of CP. The trend of frequency distribution of gene polymorphism above in Dongxiang was the same as that of Hui. Conclusion The present study reveals that IL-1B+3954C/T genotypes are significantly associated with the risk of CP. These results indicate that genetic polymorphism is significantly associated with the risk of CP among the Hui and Dongxiang minorities in Gansu province.

Objective To probe into the function of stem cell antigen-1（Sca-1） in cell proliferation and differentiation. Methods Sca-1+ and Sca-1- muscle derived cells were separated from C57BL/6 mice by fluorescence-activated cell sorting and then cultured in vitro. After 5 days cells proliferative curve were drawn according CCK-8 experimental results. Western blot also were done to detect Sca-1, MyoD and Myogenin expression in cultured Sca-1+ and Sca-1- muscle derived cells. Results The difference of the proliferative curve of Sca-1+ and Sca-1- muscle derived cells cultured 3 days in vitro was not apparent, but Sca-1- muscle derived cells had a accelerated division rate in the follow days compared to the Sca-1+ muscle derived cells. Sca-1 expression in both cells was not obvious. MyoD and Myogenin expression were stronger in Sca-1+ than Sca-1- muscle derived cells. Conclusion Sca-1 expression in muscle derived cells takes a period of time that related to the beginning and ending of the cell cycle.

Objective To study the effect of piezosurgery in the extraction of mandibular impacted third molars. Methods 228 mandibular impacted third molars with relative difficulty for extraction according to the scheme of degree of difficulty for extraction were included in the study, and were divided into two groups（114 teeth each group）: Test group（treated by piezosurgery）, control group（treated by traditional chisel osteotomy）. The surgery time and pain. restriction of mouth opening and facial swelling after surgery, were evaluated in both groups. Results The average surgery time was （16±5.2）min in test group and （30±8.7）min in control group. The surgery time, pain, facial swelling rate, and restriction of mouth opening were lower than control group（P<0.05）. Conclusion Compared with traditional chisel osteotomy, the average surgery time with piezosurgery was significantly shorter and the complications are obviously reduced.

Objective To assess the effect and safety of periodontal therapy in relieving the symptoms and clinical signs of rheumatoid arthritis（RA）. Methods The electronic search was conducted in Medline（OVID, 1950—2010 Sep）, EMBASE（1984—2010 Sep）, CENTRAL（2010, Issue 3），CBM（1978—2010 Sep） and the Chinese journals on stomatology were hand-searched. Clinical randomized controlled trials as well as clinical controlled trials were selected regarding the targeted issue. Two investigators evaluated the reporting quality and risk of bias of those included trials in accordance with CONSORT statement and Cochrane risk of bias assessment tools, and collected data of included studies in duplicate. Revman 5.0.23 was applied for Meta-analysis. Results Four trials met the inclusion criteria and a total of 150 patients were enrolled in the trials, one had low risk of bias and others had moderate risk of bias. Metaanalysis showed that pure periodontal therapy could not decrease disease activity score in 28 joints（DAS28）（P=0.06）, and there was no statistically significant difference between periodontal therapy with anti-tumor necrosis factor-α（TNF- α） medication and pure anti-TNF-α medication（P=0.24）. But the subgroup analysis showed that a significantly decreased DAS28 was achieved by periodontal therapy（P=0.03）, and the interventions provided a remarkable effect on alleviating clinical signs and erythrocyte sedimentation rate of RA（P<0.05）. Results of the symptoms relief differed from the studies. No adverse events were reported. Conclusion The evidence available currently indicates that periodontal therapy may play a positive role in remitting the clinical signs and periodontal status of RA except the relief of the symptoms.

Objective To evaluate the oral health-related quality of life（OHRQOL） in type 2 diabetic patients with chronic periodontitis. Methods A total of 80 type 2 diabetic patients with chronic periodontitis who had at least 16 teeth and never accept any periodontal therapy in latest one year were recruited. The clinical periodontal index such as probing depth, attachment loss（AL）, modified bleeding index, plaque index were obtained with a Williams type periodontal probe. All accepted structured questionnaire interview including the evaluation of OHRQOL. Results The geriatric oral health assessment index（GOHAI） results demonstrated good content validity, construct validity and responsibility. The periodontal index had positive correlation with the GOHAI scores. Individuals with self-unsatisfied of oral health status, using hypoglycemic drugs, accompanied with serious gingival inflammation and higher AL had relatively poor OHRQOL. Conclusion The OHRQOL of type 2 diabetes with chronic periodontitis and the negative experiences of items listed in GOHAI questionnaire were affected by self-conscious of oral health and periodontal inflammation status.

Objective To examine the hypothesis that functional appliances enhance mandibular growth in the treatment of skeletal Class Ⅱ malocclusion. Methods A literature search was performed in electronic databases according key words “skeletal Class Ⅱ malocclusion”, and full texts of selected articles were collected by hand-made method. The data were extracted from the articles. The quality of the trials was evaluated and meta-analysis method was used to analyze the data through RevMan 4.2. Results 19 articles could be qualified for the final analysis. Those indices including SNB（Activator, Twin-block，Herbst group）, Go-Gn, Co-Pg, Co-Gn, Co-Go, demonstrated significant effect of functional appliances on mandibular growth in comparing with those of untreated control group. There were no significant differences between the two groups for the indicies of SNB（Frankel-Ⅱ） and Go-Me. Conclusion Functional appliances can enhance mandibular growth in treatment of skeletal Class Ⅱ malocclusion. This mainly dues to the growth of the ramus instead of changes of mandibular body length.

Objective To compare the reaction of children receiving computer-controlled local anesthetic delivery system（CCLADS） and a conventional syringe, and evaluate the efficacy of anesthesia and the reaction after treatment. Methods 30 children aged 4 to 9 years old, whose bilateral primary molars in the same jaw present similar lesions with similar treatment were included in the study. These bilateral primary molars were treated under local anesthesia in 2 separate visits with random use of either the CCLADS or conventional syringe. For the first visit, the first group received CCLADS anesthesia, in which buccal infiltration anesthesia was performed for maxillary primary molars, and periodontal ligament anesthesia was performed for mandibular primary molars. The second group received conventional anesthesia, in which buccal infiltration anesthesia was performed for both maxillary and mandibular primary molars. For the second visit, two groups used alternative anesthestic method. Pain behavior was observed and scored by modifiedchildren’s hospital of eastern ontario pain scale（MCHEOPS）. Pain perception was rated using facial image scale（FIS）. Results The MCHEOPS and FIS scores in 1 min injection of children with CCLADS were lower than children with conventional syringe（P<0.05）. No difference was found in the FIS score in treatment between two injectors（P>0.05）. Conclusion In local anesthesia, CCLADS can reduce the injection pain caused by conventional syringe to a certain
extent.

Objective To evaluate effectiveness of low-level laser therapy（LLLT） on temporomandibular joint（TMJ） pain. Methods The patients with TMJ pain were randomly assigned laser group（n=21） or control group（n=21）, once a day for 6 consecutive days of treatment. TMJ pain and function were measured at baseline, just after treatment course, 1 month and 2 months after the treatment. Results The changes of visual analogue scale（VAS） were app earing over time in both groups but presented statistically significant differences between groups（P<0.001）. VAS of laser group decreased faster than that of control group. The same tendency occurred for painless maximum vertical opening （MVO）, left lateral excursion（LLE） and right lateral excursion（RLE）, which increased faster in laser group. There were no statistically significant differences between groups and evaluation times for protrusion excursion（PE）, but an interaction between group and evaluation times existed and should be explored further. Conclusion LLLT is an appropriate treatment for TMJ pain.

Objective To observe the effective of presurgical nasoalveolar molding（PNAM） therapy in the treatment of complete cleft lip and palate infant. Methods PNAM was performed as presurgical orthodontic treatment in 45 infants（aged 18.33 d） with nonsyndromic complete cleft lip and palate. The columella deviation, columella length, nostril width, nostril height and width of alveolar cleft were measured before and after treatment. The data were analyzed by SPSS 10.0. Results After PNAM treatment, the columella deviation, columella length, nostril width and width of alveolar cleft obviously decreased, while the nostril height increased. Except for smaller cleft nostril width of bilateral complete cleft lip and palate infant, other measurement items had statistics difference（P<0.05）. Conclusion PNAM can improve nasal profile of complete cleft lip and palate infant and decrease the width of alveolar cleft, and make it easy for the operation of cleft lip and palate.

Objective To explore the surgical technique of a modified Onizuka cheiloplasty for repairing the unilateral cleft lip. Methods 24 patients with unilateral cleft lip were repaired by modified Onizuka cheiloplasty. The rotation flap ended at the midpoint of nasal columella crease. A small triangle skin flap was formed above the vermilion border of the advancement flap. The small triangle flap was inserted to the medial side after the Cupid’s bow was built. The skin of the flap C was denuded along the nasal columella crease and the muscle was sutured to the alar base for augmentation of nostril floor on the cleft side. The tip of the advancement flap was sutured at the midpoint of nasal columella crease and the skin of nasal floor was trimmed to hide the incision line around the nasal columella base. Results It was found that the Cupid’s bow was rebuilt in a natural form and the configuration of the upper lip was reconstructed symmetrically. The long term follow up studies showed that the philtrum column was not disturbed by the small triangle flap and the nasal floor was rebuilt without obvious scars. Conclusion The modified Onizuka cheiloplasty is an easy learning technique and efficient for repairing the unilateral cleft lip. This technique can satisfy the patients by reducing the length of scar as well as rebuilding a natural form of upper lip and nostril floor.

Objective To investigate the expression of cytokeratin 17（CK17） in oral squamous cell carcinoma（OSCC） as well as its clinical significance. Methods Detection of the mRNA level and protein expression of CK17 in the in vitro cellular carcinogenesis model of OSCC, some OSCC cell lines and tissue specimens from 30 primary OSCC patients were performed using real-time polymerase chain reaction（PCR）, Western blot and immunohistochemistry, respectively. Results Increased CK17 mRNA level was observed in the HB56 and OSC cell lines compared with the HIOEC using real-time PCR technique. Western blot showed increased CK17 protein expression in all the cell lines compared with the HIOEC. Increased CK17 mRNA and immunoreaction levels were also observed in the cancerous tissue specimens from OSCC patients compared with normal adjacent tissues（P<0.01）. Conclusion The significantly increased CK17 gene may be associated with the tumorigenesis and development of OSCC.

Objective To investigate the combined effects of platelet-derived growth factor-BB（PDGF-BB） and insulin-like growth factor-Ⅰ（IGF-Ⅰ） on the expression of integrin β3 protein in the periodontal tissues of the compressing side of orthodontic tooth in rats. Methods Establishing orthodontic movement model in Sprague-Dawley rats， which were injected with 10 ng PDGF-BB，200 ng IGF-Ⅰ alone or in combination in the buccal submucosal area of the orthodontic tooth. The injection was applied every other day. The experiment continued for ten days and then the rats were sacrificed. The expression of integrin β3 protein in periodontal ligament tissues of the compressing side was detected by immunohistochemical techniques. Results The expression of integrin β3 protein in periodontal ligament tissues of the compressing side of each experimental group was significantly increased compared with that of the control group（P<0.01）. Meanwhile the maximum mean optical density value of integrin β3 protein expression was attained in the combination group which showed a significant increase compared with the PDGF-BB group（P<0.05） and the IGF-Ⅰ group（P<0.01）. Conclusion The combination of exogenous PDGF-BB and IGF-Ⅰ in orthodontic tooth movement may enhance the expression of integrin β3 protein in periodontal ligament cells and PDGF-BB and IGF-Ⅰmay have a synergistic effect during orthodontic tooth movement.

Objective The purpose of this study was to establish a palatal organ culture method and to investigate the palatogenesis in vitro. Methods 20 pregnant 14-day mice were killed, embryos were separated ascetically, and palatal shelves were dissected and placed on a modified Trowell’s system. All explants were cultured 24 h and 48 h respectively. Finally, all explants were embedded and stained by Hematoxylin and Eosin. Results All explants grew healthy. After incubation for 24 h, medial edge epithelium maintained, whereas after 48 h, medial edge epithelium disappeared, bilateral mesenchymal cells contacted, palates fused. Conclusion This method provides an effective way for investigating the etiology of cleft palate in vitro.

Objective To observe the effect of lipopolysaccharide（LPS） and interleukin-1β（IL-1β） on the expression of inducible nitric oxide synthase（iNOS） gene and nitric oxide（NO） in human periodontal ligament cells（hPDLCs）. Methods After stimulating hPDLCs by LPS and IL-1β, RT-PCR had been used to identify the expression of iNOS gene. The activity of iNOS in the culture was quantitated by enzyme-linked immune sorbent assay （ELISA）. And the level of NO was determined by nitrate reductase method. Results Slight amount of iNOS and NO had been detected in hPDLCs without sitimulation, but when stimulating with LPS and IL-1β, the amount of the iNOS mRNA increased significantly in the cells in the time and dose dependent way（P<0.05）. Under the stimulation with the same time or same dose, the productions of iNOS and NO stimulated by IL-1β and in combination with LPS were larger than that stimulated with LPS（P<0.05）. Conclusion The expression NO and iNOS could be increased by stimulating hPDLCs with LPS and IL-1β, which may contribute to the research on injecting LPS and IL-1β at periodontal tissue of animal models.

Objective To observe the expression of inducible nitric oxide synthase（iNOS） in rat dental pulp after direct pulp capping with calcium hydroxide（CH） and mineral trioxide aggregate（MTA）. Methods Samples from 42 Wistar rats were immediately collected at 1, 3, 7, 14, 21 and 28 days after direct pulp capping with CH and MTA. Pulp tissues were studided with immunohistochemical stain. Software for image analysis was used to test the optical density of each specimen. The data were analyzed by paired t-test and Dunnett-t test with SPSS 11.5. Results In normal pulp, the stain of iNOS was negative. After direct pulp capping with CH or MTA, iNOS expression demonstrated weakly positive, positive, weakly positive, negative at different time, the expression was low immediately after capping but became strong after 3 days. Until 7 days the stain became less positive gradually and at 21 days the stain approached normal. The expression was mainly at the fibroblasts, odontoblasts, vascular endothelial cells, neutrophils, etc near the bottom of the pulp capping agent. The diffence of iNOS expression was significant 3 days after direct pulp capping with this two capping agents. Conclusion After direct pulp capping, iNOS expression increasd at first and then decreased, the diffence of capping agents will have an impact on the expression of iNOS 3 days after direct pulp capping.

Objective To establish a novel nude mice model which can be visualized in real time and detected in a continuous and dynamic way for the development and metastasis of adenoid cystic carcinoma. Methods Human adenoid cystic carcinoma cells, ACCM cell line, were infected with retroviral vector of pLEGFP-N1 and then screened for a single colony of ACCM-GFP cells. Cell proliferation and morphological analysis were conducted for ACCM and ACCMGFP cells. Nude mice lingual carcinoma model was set up with ACCM-GFP cells injection and real time observation with fluorescence imaging on ACCM-GFP tumors was performed subsequently. Histological assay was analyzed for ACCM and ACCM-GFP tumors as well. Results ACCM-GFP cells were able to express GFP stably in the long term. ACCM and ACCM-GFP cells showed no significant difference in cell proliferation and morphology, and no significant difference of histological characteristics in vivo could be found between ACCM and ACCM-GFP tumors. Tumor development could be monitored in real time with fluorescence imaging system in vivo. Conclusion GFP-expressing ACCM tumor model can be applied to detect and observe its development in the long term in a noninvasive, real time and dynamic way. It is also a kind of ideal in vivo mouse model for adenoid cystic carcinoma research.

Objective The purpose of this study was to establish an indirect co-culture system of rat apical toot germ-conditioned medium（APTG-CM） and periodontal ligament cells（PDLCs）. Methods PDLCs were isolated and cultured through the method of enzyme-digestion. Vimentin and cytokeratin（CK） were used to demonstrate the cells’ mesenchymal derivation. Co-culture system of APTG-CM and PDLCs for 28 days, osteocalcin（OCN）, collagen typeⅠ （COL Ⅰ） and bone sialoprotein（BSP） were detected in PDLCs by immunocytochemistry. Morphological changes were observed by inverted microscope. With building a transplant by dental tube, periodontal ligament cell sheet and ceramic biologic bone（CBB） in vitro, then, the combinations of dental tube and PDLCs incubated by APTG-CM were implanted subcutaneously into athymic mice for 8 weeks. Results This study demonstrated that cellular cementum-like tissue formed along the dentin surface and CBB, with fibrous tissue adjacent or inserted into CBB in vivo. PDLCs were grown better in the CBB than in dentin tubes. And the vertical fibers can’t embed in the control. Conclusion PDLCs, embedded within this APTG-CM, exhibite several phenotypic characteristics of cementoblast lineages. Thereby it contributes to the main processes of periodontal tissue regeneration with rat APTG-CM.

Objective To research the effects of incorporating tetrapod-like zinc oxide whisker（T-ZnOw） of different proportions on the antibacterial activity of different kinds of soft denture liners. Methods The minimal inhibitory concentration（MIC） and minimal bactericidal concentration（MBC） of T-ZnOw against Saccharomyces albicans（S.albicans） were examined by the broth dilution test. Add T-ZnOw 0%, 1%, 2%, 3% to Silagum soft denture liners and soft denture liners respectively. The antimicrobial rate of S.albicans was determined by the membrane covering method. Results The MIC of T-ZnOw against S.albicans was 78 μg·mL-1 and the MBC was 156 μg·mL-1. Comparing 1%，2%，3% T-ZnOw group with control group, the results showed significant difference（P<0.05）. And as the T-ZnOw antibacterial agent added ratio increased, antibacterial increased significantly. Conclusion The soft denture liners incorporating with 1%, 2%, 3% of T-ZnOw can improve antibacterial activity. Following the increased proportions of T-ZnOw, antibacterial rate was significantly increasing.

Objective To construct the eukaryotic expression vector，encoding major histocompatibility complex class Ⅰ-related chain A gene（MICA）, for the further research of transfecting Tca8113-Tb cell line（a metastatic cell line of brain metastasis from human tongue cancer Tca8113 cells in nude mouse）, and to establish a stable MICA overexpression oral squamous cell line. Methods cDNA of MICA gene from pCMV-SPORT6-MICA was amplified by PCR，and subcloned into eukaryotic expression vector pEGFP-N1 marked with green fluorescent protein（GFP）. The recombinant plasmid was sequenced and transfected into Tca8113-Tb cell line by lipofectamineTM 2000. After screen culture by G418, stable tranfected Tca8113-Tb cell line was established using definite dilution method. The expressions of GFP protein was viewed directly with fluorescence microscopy and the overexpression of MICA was identified by RT-PCR, real time PCR and immunocytochemistry. Results The MICA gene was amplified by PCR and then cloned into the vector, whose sequence was identical to that in the GenBank. The transfected cells showed the expression of GFP. And the overexpression of MICA gene in transfected cells was detected by RT-PCR, real time PCR and immunocytochemistry. Conclusion The recombinant eukaryotic expression vector pEGFP-N1-MICA has been constructed successfully and stably expressed in Tca8113-Tb cell line，providing a foundation for further studies on the function of MICA in vitro.

Objective To construct functional tissue-engineered bone with cell sheet technology and method of traditional bone tissue engineering. Methods Canine bone marrow mesenchymal stem cells（BMSCs）were isolated with the method of density gradient centrifugation and cultured. BMSCs were induced to differentiate into osteoblasts and cultured in temperature-responsive culture dishes at 37 ℃, 5%CO2 and saturated humidity. BMSCs cell sheet was prepared when temperature was changed to 20 ℃. Demineralized bone matrix（DBM） and platelet-rich plasma（PRP） were prepared, and complex of DBM/PRP/BMSCs cell sheet/BMSCs was construsted and implanted under the left latissimus dorsi muscle. Complex of DBM/PRP/BMSCs was implanted under the right latissimus dorsi muscle. Results When temperature dropped at 20 ℃, BMSCs detached automatically from the temperature-responsive culture dishes and formed an intact cell sheet. The osteogenesis of the DBM/PRP/BMSCs cell sheet/BMSCs group was better than that of the DBM/PRP/ BMSCs group. Conclusion Cell sheet technology combined with traditional bone tissue provides a new way for construction of ideal functional tissue-engineered bone.

Cervical ectopic thymus rarely occur. We reported a case of cervical thymus presenting as a unilateral neck mass in an infant. Ultrasonography showed a low echo-level mass with clear border and abundant blood flow signal in the left neck. Preoperative chest CT revealed normal structures in the superior mediastinum including the thymus. Surgical resection was performed and the histological diagnosis was ectopic cervical thymus.

Supernumerary teeth is one of the teeth dysplasia that the number of teeth exceeded normal. Most of supernumerary teeth reported were located in anterior teeth region, but rare cases were reported in molar region. This paper reported three cases that supernumerary teeth located in molar region.

Hereditary gingival fibromatosis（HGF） is a rare hereditary condition characterized by a slow, progressive increase in the gingival tissue. A case of HGF was reported and relevant literature of HGF were reviewed.