Objective　To observe the heterotopic osteogenesis of autogenousmarrowstromal cells loading on porous calci- um phosphate ceramic scaffoldswith rhBMP2gene transfection in a Sprague-Dawley ratmodel.Methods　Autogenous marrowstro- mal cells were obtained from left femurs and tibias of 20 male adult SD rats under general anesthesia and sterile condition and cul- tured inα-Minimal Essential Medium supplemented with 15% fetal bovine serum. RhBMP2gene was transfected into stromal cells by means of LipofectAMINETM2000 reagent five days after primary culture. The stably gene expressive cells were selected with G- 418 for 14 days and mixed with stromal cells without transfection. The mixture cells were seeded and subcultured for another 10 days in porous calcium phosphate bioceramic that had been subjected to surface-modification via soaking in human plasma fibronec- tin. The cell-ceramic compoundwas implanted subcutaneously and intramuscularly in the corresponding rat. Lab animalswere sac- rificed at two-week intervals till twenty weeks postoperatively and the involved samples were removed.Results　Morphologic and histological study demonstrated that cell-ceramic compound had an ability of heterotopic osteogenesis, which was similar to that of autogenous osteoblasts in previous study.Conclusion　It seems that autogenous stromal cells with rhBMP2transfection acts as a bioreactor promoting proliferation and differentiation of stem cells when they are replanted into the corresponding animals.

Objective　To study the effect of poly D,L-lactic acid (PDLLA) screws with PDLLA-rhBMP compound on bone regeneration in the screwholes and fracture ends of dogmandibles.Methods　Aself-control studywas carried out in 4 dogs. PDLLA/rhBMP-2 compound screws were implanted to fix the mental fractures and PDLLA screws were used as control. The sam- ples from mandibleswere collected at 4, 8, 12, 16 weeks after implantation and observed by radiography and histology.Results　 All dogs showed a greater degree of bone regeneration around PDLLA/rhBMP-2 screws than PDLLA ones and all fractures were fixed and healed well.Conclusion　The PDLLA-rhBMP screwhas a better effect of inducing osteogenesis than PDLLAscrew, and is able to exert a good fixation to fracture.

Objective　To observe mandibular fracture healing after synthesized bioabsorable poly-para-dioxanone (PDS) ligature fixiation.Methods　Para-dioxanone monomer was prepared by chemical reactions of metallic sodium, ethylene glycol and other rawmaterials. PDS was synthesized by polymerizing the purified para-dioxanone in the presence of catlyst under the condi- tions of negative pressure and certain temperature. PDS ligaturewas obtained by processingthe polymer into small granules, drying and melt-extruding through a spinnerette. Eighteen adult male NewZealand rabbitswere assigned randomly into two groups. After mandibular fracture modelswere created, reductions of the artificial fractureswere accomplished bymeans of transosseous PDS lig- atures on each of 12 rabbits in experimental group. While the other six rabbits without any internal fixation were set as control. Schedules for killingwere arranged to give postoperative samples at two-week interval till 12thweek.Results　Radiographical and histological examinations demonstrated that all fractures fixed with PDS ligatures healed without any complication. Periosteal and cartilaginous osteogenesis was observed in newly formed external callus. In contrast, bone fragment migration and the consequent nonunion occurred in the control group. PDS ligature degraded and absorbed without interference with osseous union and healing. The tensile strength reduction of PDS ligature was prior to its absorptionin vivo.Conclusion　The synthesized PDS is a colorless, flexible, themoplastic and monofilament fiber, which can be sterilized by ethylene oxide embalmmentwithout serious loss of tensile strength. It seems that the application of this macromolecular material in internal fixation is of great worth for further study.

Objective　The purpose of this studywas to observe the behavior of bone formation around the titanium-hollow porous cylinder implant composed of bovine bone morphogentic protein(bBMP).Methods　Porous-hollow cylinder titanium im- plant composed of bBMP was implanted into mandibule of dogs. Multiple fluorescentwas labeled at different times and then LSCM was used to observe the newly formed bone around the complex implant.Results　The newly formed bone around the complex im- plant in experimental group was more obvious than that in other groups.Conclusion　Earlier, longer and more new-bone forma- tion can be induced by porous-hollow cylinder titanium implant composed of bBMP, and LSCM is an effective method to observe new bone formation around implant.

Objective　The purpose of this article is to discuss the reconstruction of facial muscle defectswith tissue engi- neered myoblast in SD rats.Methods　Using purified, subcultured myoblast of neonatal rats and typeⅠcollagen gels as extracel- lular matrix (ECM) and scaffold, tissue engineered musclewas transplanted in the face of syngeneic mutured rats.Results　Tissue engineered myoblast generated and differentiatedin vitrowere observed with microscope. Myoblast fused each other and formed myofibers in the face of rats, nerve fibers and vessels regeneration could also be found in some samples. Postoperative electromyo- graphs showed the myofiberswere active when stimulating the nerve trunk that innervates the engineered facial muscle.Conclusion 　Tissue engineered method is hopeful to be used as a new technique to reconstruct defects of facial muscle.

Objective　The purpose of this study was to screen sialyl Lewis(a)(sLe(a)) in the tumors of patients with oral squamous cell carcinoma (OSCC) and to explore the association of sialyl Lewis(a) expressionwith local lymph node metasta- sis.Methods　Specimen from 38 patients with primary OSCC were obtained and analyzed by immunohistochemical methods.Re- sults　The expression of sLe(a) protein, but not E-selectin, of OSCCs significantly correlated to the local lymph node metastasis. sLe(a) was expressed in 79%(15/19) of the metastastic cases compared with 21% (4/19)of the non-metastasis ones, indicated the association of sLe(a) expression with the local lymph involvement.Conclusion　High expression of sLe(a) in OSCC may be related to the metastasis of cervical lymph nodes and it seems useful in predicting poor prognosis in OSCC.

Objective　To observe the temporal and spatial expression of Smad7 during human tooth germ development and evaluate the effect of Smad7 on tooth germ development.Methods　The expression of Smad7 and its changes at different stag- es of human tooth germwere detected by using immunohistochemical staining.Results　Smad7 was expressed at all stages of tooth germ, but the distribution patterns at various stageswere different. It indicated thattemporal and spatial expressingmode of Smad7 during human tooth germ developmentwas specific, whichwas similartothat ofTGF-βand its signal transducerSmad2/3.Conclu- sion　Smad7 might play an important role in TGF-βintracellular signaling for modulating the differentiation of ameloblasts and odontoblasts.

Objective　To study the expression of telomerase reverse transcripatase (hTERT) and bcl-2 in ameloblastoma (AB).Methods　hTERTmRNA in 54 cases of AB (primary AB 31 cases, recurrent AB 17 cases, malignant AB 4 cases) and 7 cases of oral normal mucosa was detectd by in situ hybridization, and bcl-2 by S-Pmethod.Results　The expression of hTERT mRNAwas negative or weak in normal oral mucosa (14·3%), moderate or strong in AB (94·4%). There was a significant dif- ference in these two groups (P<0·001). The difference between the expressions of hTERT in primary, recurrent and malignant AB was significant (P<0·05). The positive ratio of bcl-2 in AB and normal oral mucosa was respectirehy 88·0%, 44·4%. There was a significant statistical difference in these two groups (P<0·001). hTERTmRNAwas stronger in recurred or malig- nantly transformed AB (P<0·05).Conclusion　The expression of hTERTand bcl-2 is stronger in recurred ormalignantly trans- formed AB, and it could be used as an indicator of AB prognosis. Telomerase activity and bcl-2 expression play an important role in genesis and development of AB.

Objective　To evaluate the effect of locoregional immunotherapy of interleukin 2 (IL-2) in combination with chemotherapy upon intratumoral lymphocytes in oral squamous cell carcinomas.Methods　Thirty-four patientswith stageT3 orT4 oral squamous cell carcinoma were randomly divided into two groups, and treated with two therapies. 23 cases of them received immunochemotherapy and 11 cases received PVP chemotherapy. Changes ofT lymphocyte subsets and B cells at tumor site in the two groups were compared before and after therapy.Results　The relative numbers of CD4+,CD8+,CD20+before and after treatment in immunochemotherapy were respectively 36.96, 35.65, 28.65 and 56.61,38.52,38.70. The numbers of CD4+, CD20+increased significantly after immunochemotherapy. However, in chemotherapy group, there was no significant difference in numbers of CD4+,CD8+and CD20+cells between pre and post treatment.Conclusion　Immunochemotherapy for oral squamous cell carcinomas may play an important role in increasing local immunity.

Objective　The aim of this studywas to investigate the target delivery of Cucurbitacin BE (CuBE) to cervical lymph nodes by peri-oralcancer submucosal injection of the average diameter 85nm Cucurbitacin BE polylactic acid nanoparticles (CuBE-PLA-NP) and evaluate its clinical therapy efficacy.Methods　CuBE and CuBE-PLA-NP were respectively injected into perioralcancer submucosa at 2、12、24、48、72、96、120、144、168 and 192 hours before operation in 26 patients with oral cancer. The concentrations of CuBE in cervical lymph nodes and bloodwere measured by high performance liquid chromatography (HPLC) at every time point. Cancer cell degeneration and necrosis in metastasis foci of cervical lymph nodeswere observed using light mi- croscope and electron microscope.Results　(1)The CuBE concentrations in cervical lymph nodes after CuBE-PLA-NP injection were far higher than those after CuBE injection at every time point, the duration of CuBE existing in the cervical lymph nodes in CuBE-PLA-NP group was far longer than those in CuBE group, the area under the CuBE concentrations-time curve of the cervical lymph nodes in CuBE-PLA-NPgroupwas 43.67 times asmany as that in CuBEgroup; (2)The CuBE ratio ofmaximum concentra- tions in the cervical lymph nodes in CuBE-PLA-NP group was 106.46 times as high as that in CuBE group; (3) The CuBE con- centrations in the blood in CuBE-PLA-NP groupwas far lower than that in CuBE group; (4)Cancer cell necrosis and degeneration in the metastasis foci of cervical lymph nodes were found in CuBE-PLA-NP group, necrosis and degeneration were not found in CuBE group.Conclusion　The perioralcancer submucosa injection of the average diameter of 85nm CuBE-PLA-NP can specifical- ly deliver CuBE to the cervical lymph nodes, enhance treatment efficiency, and reduce general toxicity.

Objective　To analyze the formant frequency of vowels in the sequence therapy of patient with cleft palate. Methods　The formant frequency of vowels [a],[e],[i],[u] of normal children and postoperative patients with and without speech therapy was measured and analyzed by VS-99.Results　①The mean value of F1,F2,F3 of [a] did not show significant difference among the three groups (P>0·05).②The difference of mean value of [e] was significant between control group and pre-speech-therapy group, and between pre-speech-therapy and post-speech-therapy group (P<0·05), but no significant differ- ence was found between post-speech-therapy and control group(P>0·05). The mean value of the formant in post-speech-therapy was higher than that of pre-speech-therapy.③The difference of mean value of [i] was significant between pre-speech-therapy and post-speech-therapy (P<0·05), the mean value of F2,F3 in post-speech-therapy group decreased significantly compared with control (P<0·05).④The difference of mean value of [u] showed significance between pre-speech-therapy and post-speech-ther- apy (P<0·05), while the differences among other groups were insignificant (P>0·05).Conclusion　Surgical repair of cleft palate cannot make all patients obtain perfect Velopharyngeal competence (VPC), while speech therapy can improve patient’s pronunciation. Speech spectrum analysis can judge the effect of cleft palate therapy objectively.

Objective　The purpose of this study was to evaluate the color masking ability of Computer Aided Design/ ComputerAided Manufacture(CAD/CAM) machining ceramic Vita Mark II, this ability was affected by thickness and shade. Methods　Each of 5 specimens of 0·5 mm, 1·0 mm and 1·5 mmVitaMark II A3C/18 and A2C/18 were prepared and the color change was measured after the substrate simulating stained teeth was covered with the specimen.Results　Statistically significant differences (P<0·01) were recorded in the substrates covered with different thickness and shade of Vita Mark II. The color changes (△E) were 15·181, 17·691, 19·667 and 15·653, 16·880, 18·002 afterthe substrateswere coveredwith 0·5 mm, 1·0 mm and 1·5 mmVitaMarkⅡA3C/18 and A2C/18.Conclusion　As a dental material, CAD/CAMVitaMark II has high quality to mask the underlying color. Being a veneer, the masking abilitywith A2C/18 is better than thatwith A3C/18, but being an in- lay, the result is reverse.

Objective　Standards for determining mandibular position, especially the centric relation (CR), are in cont- roversy because of anatomical, neurophysiological factors and research methods or instrument. The purpose of this studywas to re- evaluate the reproducibility of centric relation of the patients with severe dental attrition for oral rehabilitation.Methods　Repro- ducibility of the centric relation of 6 patientswith severe occlusal attritionwas investigated by using D5ADenar fully adjustable ar- ticulator and the Pantronic recording system.Results　①In supine position, anterior-posterior(AP) displacement of centric rela- tion (CR) was 0·14 mm and superior-inferior(SI) displacements of CRwere between 0·11 mm~0·12 mm.②In upright position, anterior-posterior displacement of CR was 0·35 mm and superior-inferior changes of CRwere between 0·13 mm~0·20 mm.Con- clusion　The CR is the most stable and reproducible position of mandibule in normal stomatological system and is useful as a ref- erence position in occlusal treatment and functional rehabilitation.

Objective　To studythe clinical effects of demineralized dentinmatrix (DDM) as a apexificating agent.Meth- ods　Human teeth were crushed into fragments and were defated, demineralized, lyophilized to produce DDM. The DDM was used as an apexificating agent to treat 57 teeth compared with calcium hydroxide. X-ray film and clinical observation were under- taken after half a year, one year and two years.Results　One year later, a barrier in the tooth apexwas found in the X-rays film. Then permanent filling material was used. After two years, DDM group had a healing rate of 92·86%, was higher than that of 91·30% in calcium hydroxide group, but there were no statistical significance.Conclusion　The findings suggest that DDM can be used as a new apexificating agent. One year after the apexification is the best opportunity to change the apexificating agent to a permanent root canal filling material.

Objective　To study the effect of ClassⅢintermaxillary functional orthopedic force on the remodeling of pu- bescent Rhesus monkeys’TMJ for different lengths of time.Methods　Six pubescent Rhesusmonkeyswere divided intotest group and control group. Monkeys in the test groupworeTMAⅢwhile the control group did not. Cephalometric technology and CTscan- ning were employed in this study.Results　①Compared with the control groups, the cephalometric results showed that the rela- tionship of the occlusion changed in the test groups. The growth of the maxilla was promoted and the development of the mandible was inhibited, but the mandibular lengthwas not decreased.②Compared with the control groups, CTscanning results showed that the posterior space ofTMJ in the test group narrowed and the anterior spacewidened. Therewas a statistical difference between the test group and the control group(P<0·01), but no difference within the test group.Conclusion　Under ClassⅢOrthopedic therapy, the occlusion relation was changed. The growth of maxilla was promoted and the development of mandible was inhibited. The posterior space of TMJ narrowed and the anterior space widened in test group.

Objective　This study is to make sure if the constructed pcDNA3 carrying encoding gene of sIL-1R can be expressed in mammalian cellsin vitro.Methods　COS-1 cells and CHO cells were respectively transfected with recombinant plasmid pcDNA3/sIL-1R by liposome. The protein expression products were detected by ELISA.Results　The results indicated that the protein expression products could be detected in the cell plasma and the cell culture supernatant. The expression level in experimental groups was much higher than that in control groups(P<0·05).Conclusion　The constructed pcDNA3/sIL-1R can express interest protein in mammalian cells and this establishes the basis for future investigation on gene therapy of periodonititis and other inflammatory diseases.

Objective　To elucidate the histocompatibility of tissue engineered rat skin through studying the effect ofTNF- αand IL-2 in immunological rejection after rat skin allograft.Methods　Tissue engineered skin thatthe basic materialswere taken from neonatal SD rats was cultured in lab, grafted to adult Wistar rats. The expressions of TNF-αand IL-2 in grafted tissue were detected with immunohistochemical staining and Western blot.Results　The expressions of TNF-αand IL-2 were remarkable in skin allograft group, but low in tissue engineered skin group.Conclusion　The expressions of TNF-αand IL-2 and the immuno- logical rejection were closely related after skin allograft, but the tissue engineered skin has favorable histocompatibility and doesn′t arose obvious immunological rejections.

Objective　To study the effects of artificial bone composite of bicoral,rhBMP-2 and PLA in repairing calvarial critical-size defects.Methods　Calvarial defects in 24 rabbitswere surgically made and then half of the defectswere repaired with the artificial composite bone. Another half of themwere repairedwith bicoral/PLA composite and served as controls. Four rabbits in each group were sacrificed at 4,8,12 weeks after operation, respectively. The treatment effects were evaluated with scanning electron microscopy and mechanical strength testing.Results　New bone was observed not only in the periphery, but also inside the artificial bone in both groups, but earlier and more newbone formationwas observed in treatment group compared with control group. The mechanical strength test showed that the artificial bone in two groups, which had same mechanical strength before im- plantation, had significant different mechanical strength after operation. The strength of the artificial composite bone was higher than that of controls and was same with normal rabbit calvarial bone.Conclusion　The artificial composite bone possess a highly repairing ability, and the healing in bone defects may be accomplished by both osteoinductive and osteoconductive mechanism. The material may be used as a good substitute for bone grafting.

Objective　The aim of this studywas to investigate the delivery of Cucurbitacin BEto cervical lymph nodes by peri-cancer submucosal injection of the average diameter 85nm Cucurbitacin BE polylactic acid nanoparticles (CuBE-PLA-NP). Methods　Cervical lymph node metastasis model of mice oral cancerwas established and CuBE-PLA-NP and CuBEwere injected in pericancer submucosal of the mice respectively, the concentration in blood、heart、liver、spleen、lung、kidney and cervical lymph node were measured by high performance liquid chromatography at fifteen time points, Targeted cervical lymph nodeswere evaluat- ed by targeting index, selectivity index, targeting efficiency, relative targeting efficiency and ratio of maximum concentration.Re- sults　(1)The CuBE concentration in the cervical lymph nodes after CuBE-PLA-NP injectionwas far higher than that after CuBE injection at every time point, the CuBE duration in the cervical lymph nodes in CuBE-PLA-NP group was far longer than that in CuBE group;(2)The five targeted values of the cervical lymph nodes in CuBE-PLA-NP group was far higher than that in CuBE group;(3)The CuBE concentration in blood、heart、liver、spleen、lung and kidney in CuBE-PLA-NPgroupwas far lowerthan that in CuBE group.Conclusion　The CuBE-PLA-NP can specifically deliver CuBE to the cervical lymph nodes by pericancer submuco- sal injection, increase CuBE concentration and duration in metastasized cervical lymph nodes, and decrease drug concentration of other organs.