Objective  To investigate the possibility of adipose-derived stromal cells（ADSCs） transfeced by ade-novirus containing human bone morphogenetic protein-2（Ad-hBMP-2） gene and their osteogenic potential. Methods ADSCs were obtained from inguinal fat tissue of 4 weeks old SD rats. After exposure to adenovirus containing green fluorescent protein（Ad-GFP）, fluorescent microscope was used to observe gene transfection effect once 12 hours. After transfected with Ad-hBMP-2，cytochemistry, immucytochemistry and Western blot were used to examine the ex- pression of  alkaline phosphatase（ALP）, osteocalcin（OC） and hBMP-2. Results  After exposed to Ad-GFP 12 hours, 52% ADSCs were observed being transfected and 48 hours later reached 95%. The double number time belonged after transfecting with Ad-hBMP-2, and cytochemistry, immucytochemistry and Western blot examines indicated positive results of ALP, OC, hBMP-2 after 48 hours. Conclusion  Adipose tissue contains abundant ADSCs which could be transfected as gene vectors by adenovirus, ADSCs transfected with Ad-hBMP-2 can convert to ostoeblasts, and can act as a kind of seed cells for osteo-tissue engineering. 

Dept. of Oral Medicine，Hospital of Stomatology, Tongji University, Shanghai 200072, China）[Abstract]  Objective  To investigate the effects of overdosed fluoride on the expression of MMP-20 and TIMP-2 in rat incisor. Methods  20 Wistar rats were randomly divided into experiment group and control group. The distilled water was given in control group. 100 mg/L fluoride- was given in experiment group. After 8 weeks treatment, the rats were killed. Immunohistochemical staining was used to observe the expression of MMP-20 and TIMP-2 in rat incisors. Results  Immunohistochemical results demonstrated the presence of MMP-20 and TIMP-2 protein in ameloblasts, odontoblasts, stratum intermedium and the stellate reticulum of rat incisor. The imagination analysis results showed that the expression of MMP-20 was reduesed in experiment group（P<0.01）, and the expression of TIMP-2 had no significant difference（P>0.05）. Conclusion  The overdosed fluoride inhibits the secretion of MMP-20 and leads to the disturbed balance between MMP-20, TIMP-2 in rat incisor, which leads to the delay of the amelogenin removal and the enamel demineralization.

Objective To investigate the expression of MMP-2 and MMP-3 in periodontal tissues of rat peri-odontitis model at different stages of inflammation of varied severity. Methods The periodontal tissues were im-munohistochemically stained by antibody of MMP-2 and MMP-3. Results MMP-2 and MMP-3 were both strongly positive in gingival epithelia and fibroblasts in periodontal ligament in rat periodontitis model. And chronic periodon-titis showed lower expression of MMP-2 and MMP-3 than that of acute gingivitis and acute peridontitis. Conclusion The expression of MMP-2 and MMP-3 varies in different stage of periodontitis. MMP-2 and MMP-3 may play an important role in development of periodontitis.

Objective To investigate the regulatory mechanism of parathyroid hormone-related protein（PTHrP） in proliferation and differentiation of chondrocytes of condyle in fetal mouse. Methods Chondrocytes of condyle in fetal mouse were separated and cultured in vitro, the influence of PTHrP on proliferation and differentiation was observed. Results After two weeks′ culture in 0.01 nmol/L, 0.1 nmol/L, 1 nmol/L, 10 nmol/L human PTHrP, there was significant difference in the number of cartilage nodule formed between experiment group and control group （P<0.05）, and there was no significant difference in 0.01 nmol/L group（P>0.05）. Alkaline phosphatase（ALP） activity was significantly intensified in experiment group and control group（P<0.05）. Meanwhile, it was found that this function of promotion was lessened after anti-PTHR antibody used. Conclusion It can be seen that PTHrP, via its receptor, can promote proliferation and differentiation of chondrocytes of condyle, which resemble its modulation mechanism in epiphyseal growth plate cartilage intramembrane in mandibule.

Objective To study the effects of progressive loading on implants placed　into extraction sockets. Methods Bilateral 3rd, 4th and 2nd premolar of 4 beagle dogs were extracted and the implants were immediately inserted at 0, 14 and 21 days. The progressive loading procedure was conducted after 24 hours. The vertical bone loss（VBL） and the bone/biomaterials reactions were detected by X-ray and SEM. Results The VBL in control groups was larger than that for the experimental groups at 14, 21 and 28 days（P<0.05）. Scan electron microscopy detected that the mineralization speed of experimental groups was many times as faster as the control groups. Conclusion Progressive loading of implants placed　into extraction sockets can be performed without disturbing the osseointegration process. The potential of new bone formation in the extraction sockets and the physical strains can congenerously promote osseointegration.

Objective To evaluate the effects of different polishing methods on surface roughness of pure titanium castings. Methods 35 pure titanium castings were devided into 7 groups, used for control, mechanic polishing and electrolytic polishing, respectively. Surface roughness（Ra value） of each castings was measured with a profilometer. Surface microstructure was studied by a scaning electron microscopy, and the weight loss（Wt%） and height loss on unit area（H） before and after polishing was calculated. Results The effects of mechanic polishing with aluminium oxide or chromium oxide were acceptable. Surface smoothness was improved with acid treatment followed by electrolytic polishing. Conclusion Aluminium oxide and chromium oxide can be used in mechanic polishing of pure titanium castings, and improvement should be made on electrolytic polishing methods.

Objective To obtain the self-concept psychological feature of cleft lip and palate（CLP） adolescents further and accurately, and offer reasons for timely and pointed psychological intervention. Methods Based on the procedure and criteria of development of psychological questionnaire, a psychological questionnaire for CLP adoles- cents was designed. 93 CLP and 88 healthy adolescents were studied by using it and their half-quantified score raging 0-9 were analyzed statistically. Results ①There was no statistical difference between CLP and normal ado- lescents, scored 5.91 and 5.66 respectively, which demonstrated that the self-concept of CLP adolescents was at a normal level without obvious passive tendency. ②There was no significant difference between genders, but boys were more extroversion while girls did better on being unyielding and releasing strain. ③CLP adolescents had a higher ability of psychological regulation and could face failure more bravely. CLP patients were in a tendency of protective behavior inhibition, companied less, and maximized delight mood unconsciously to decrease harm from enviroment. ④CLP adolescents had a good parentage. ⑤A majority of patients had low expectation of life-quality. ⑥Much of CLP patients considered that speech was more important than appearance. Conclusion Self-concept of CLP adolescents have normal self-concept and do better in psychological regulation and dependence than normal ones.

 Objective  To compare the canines root resorption and alveolar bone height when they were moved into different healing extraction sites. Methods  Twenty patients with overjet were treated by extracting the maxillary first premolars. By random determination, distalization of different lateral upper canines started after 1 week and 12 weeks. Every 4 weeks use a force of approximately 100 g to distalize the canines. The experiment was ended when bilateral canines have contacted with the second maxillary bicuspids completely. Periapical radiography of the canine in the end of the distalization was made. Results  External apical root resorption and alveolar bone height of the canines have no significant difference between the different healing extraction sites. Conclusion  Tooth extraction site healing has not much effect on the canine external apical root resorption and alveolar bone height, when it was distalization. In practice, tooth movement into extraction sites can start early.

Objective  To compare the inclinations of third molars of patients treated orthodontically with and without premolar extractions. Methods  Records of 37 first premolar extraction patients and 32 nonextraction patients were examined. The pretreatment and posttreatment panoramic radiographs were analyzed. The angles were measured between the long axis of the third molar and the occlusal plane and between the long axis of the third molar and the long axis of the second molar. Changes in third molar angulations from pretreatment to posttreatment for two groups were compared by Mann-Whitney U-test. Results  There were statistically significant difference between the extraction and nonextraction groups in the median angle formed by the long axis of third molar angulation relative to the occlusal plane（P<0.05） and the second molar（P<0.05） in mandible but not in maxillary. In the extraction group, at the end of the orthodontic treatment, the mandibular third molars showed more uprighting than did the maxillary third molars. Conclusion  Orthodontic treatment involving premolar extractions improves mandibular third molar angulations.

Objective To assess the outcome of orthodontic treatment with upper jaw or upper and lower jaw extraction for Class Ⅱ division 1 malocclusion using the peer assessment rating（PAR） index. Methods 28 patients with Class Ⅱ division 1 were extracted two first premolars or second premolars of upper jaw, and 24 patients were extracted four premolars of upper and lower jaw N. The PAR was applied on pre-and post-orthodontic treatment dental casts for the fifty-two cases. Results The upper and lower jaw extraction groups had significantly higher initial PAR scores and the weighted PAR total scores（P<0.05）. Although significantly different before treatment, both groups were not statistically different after treatment（P>0.05）. Conclusion The upper and lower jaw extraction cases showed more severe dental displacement. Both treatment can acquire successful results.

Objective To investigate the root canal curvature in Chinese mandibular permanent incisors. Methods Two hundred and ninety nine Chinese mandibular permanent incisors were included in this study. The root canals were inserted with stainless steel 15# K files, and then taken radiography from the facial and proximal view by X-ray paralleling technique. Canal curvatures were evaluated by measuring the angle, the radius of the curvatures, and the length of the curved part of the canal. Based on the curved angle and the shape of curved canals, the root canals were classified. Results The curved angle, radius, and the curved canal length was 5.28°±5.52°, 16.19 mm± 12.38 mm, 4.10 mm±2.01 mm, respectively in the facial view; 9.99°±5.84°, 18.86 mm ±9.71 mm, 3.27 mm±2.39 mm, respectively in the proximal view. The prevalence of straight, light, moderate, and serve curved root canals in mandibular permanent incisors was 15.7%, 66.9%, 16.7%, and 0.7%, respectively（P<0.05） based on the curved angle. The prevalence of straight, L shape, and S shape curved root canals was 7.7%, 50.5%, and 41.8%, respectively（P<0.05）. Conclusion Most of the root canals in mandibular permanent incisors are curve.

Objective To compare the painless effect of four anesthetic methods during opening pulp cavity and undergoing pulpectomy for acute or chronic pulpitis. Methods 80 teeth of 80 patients were randomly allocated into four groups. Each group had 20 teeth. Anesthetic methods applied four different groups included block anesthesia of nerve, supraperiosteal infiltration, periodontal membrane injection and intrapulpal injection. Anesthesia doses were recorded and the pierced points, the zones of pain, the time of anesthesia action, the time of anesthesia persistence and the degrees of anesthesia were evaluated with four levels synthetic evaluation standard of anesthesia. Results Compared with periodontal membrane injection and intrapulpal injection, block anesthesia of nerve and supraperiosteal infiltration had the later time of anesthesia action and the longer time of anesthesia persistence（P＜0.05）. In four anesthetic methods, block anesthesia of nerve had the best painless effect（P＜0.05）. Conclusion Four anesthetic methods have their own superiorities, and we should select proper anesthetic methods in clinical work.

Objective  To observe the general status, subjective syndromes, objective signs and salivary secretion of xerostomia patients for studying their correlations. Methods  Eighty patients′ clinical data were collected and classified according to certain standards. The salivary secretion including the unstimulated whole saliva（UWS） and
stimulated whole saliva（SWS） in five minutes was measured by spit method. Results  Decreased UWS was the
main presentation of xerostomia which accouted for seventy five percents. Significantly statistical correlation were found between the decreased UWS and the dry mouth signs but not the age, sex and the accompany syndromes. Conclusion  Xerostomia has a high prevalence in middle-aged women with a long course and obvious regularity. The decreased UWS is the main presentation which was not caused by physiological changes of salivary glands and has no correlation with many clinical manifestations.

Objective To evaluate the effects of modified Forsus appliance in the treatment of Class Ⅱ mandibular retrusion. Methods 18 children with mandibular retrusion were selected and treated with modified Forsus appliance. Cephalometric radiographs were taken and analyzed at pre-treatment and post-treatment. Students′ t-test was used to determine if there were significant differences between pre-treatment and post-treatment. Results After 6-8 months of therapy, profiles were obviously improved. B moved forward（2.9±3.1）mm. ANB decreased（2.5±1.2）°. The overjet decreased（5.0+2.8） mm. The molar relationship was corrected to Class Ⅰ from ClassⅡ. SN-OL increased（4.3+2.2）°. There was significant difference between pre-treatment and post-treatment. Conclusion Combined with straight wire appliance, modified Forsus appliance can effectively stimulate the mandibular growth, balance the jaw relationship, and correct mandibular retrusion.

Objective  The aim of this study was to measure and analyze the anatomic characteristics of the pulp chamber of Chinese permanent anterior teeth radiographically. Methods  There were 137 human permanent anterior teeth to be used. The crown length, crown width and crown thickness were measured by vernier caliper. Labial-lingual and mesial-distal radiographs were obtained by parallel technique and Photoshop 8.0 was adopted for measuring the largest labial-lingual length, the largest mesial-distal length, the pulp chamber height and the distance between the lingual surface of the crown and the corresponding wall of the pulp chamber; the ratios of the largest labial-lingual length to the crown thickness, the largest mesial-distal length to the crown width and the pulp chamber height to the crown length were calculated. Finally the coefficients of variance were caculated. Results　　①The ratios of the largest mesial-distal length to the crown width of maxillary and mandibular canines were statistically different from those of the other anterior teeth. There was not statistically significant difference for those ratios either between maxillary and mandibular canines or among incisors. ②Indexes of the pulp chamber had higher variance than those of the external morphology. ③The distance between the lingual surface of the crown and the corresponding wall of the pulp chamber had the smallest coefficient of variance. ④The largest mesial-distal length of the pulp chamber had the largest coefficient of variance, except for the mandibular canines. Conclusion  This study provided anatomical basis for clinical work; the distance between the lingual surface of the crown and the corresponding wall of the pulp chamber could be used as a depth reference for the endodontic access, and the access should not be extended excessively in mesial-distal direction.

 Objective  To measure the permeability of human temporomandibular joint（TMJ） disc and cartilage to provide basic parameter for oral biomechanics and tissue engineering, and analyze its mechanisms of pathology and load-release. Methods  Confined compression method was used to measure the permeability（k value） of four cadavers′ TMJs, which were sampled into three parts: disc, condyle and glenoid fossa with different diameters（2 mm, 3 mm and 4 mm）. All 128 samples were tested with correspond diameter indenter. Results  Larger the sample diameter was, higher the k value became. The highest k value appeared in the disc while the lowest appeared in glenoid fossa. Conclusion  In normal condition, TMJ can suffer huge load by decreasing its permeability. Disc is weakest for the higher permeability, it′s easy-damaged region is an initiated factor of TMJ disease.

Objective  To investigate the effects on the phenotype，especially the mineralization ability of human embryonic lung fibroblasts（HELFs） by transfection with adenovirus vector ecoding human bone morphogenetic protein-2 gene（Ad-BMP-2）. Methods  The HELFs were primarily cultured, then transfected with Ad-BMP-2. The morphologic characteristics of the cells were observed. The cell proliferation, alkaline phosphatase activities, BMP-2 protein expression, and the mineralization ability were detected with the methods of MTT, ALP staining, Western blot, and alizarin red S staining, respectively. Results  After transfection, the shape of HELFs changed from silm spindle to multifigure, the cells became bigger than before. The colonies changed from unilaminar into multilaminar. The proliferation of HELFs was severely inhibited after transfection. An obvious BMP-2 lane was shown in Western blotting. Most cells presented positive in ALP staining, and large number of nacarat mineralized nodes were observed after alizarin red S staining. Conclusion  HELFs were capable of transforming into osteoblast-like phenotype, and were endowed with the ability of mineralization while being transfected with Ad-BMP-2.

Objective  The recombinant adenovirus vector carrying p14ARF gene was constructed for using in the interference therapy in signal transduction of laryngeal squamous cell carcinoma. Methods  The total cDNA fragment of p14ARF was cloned into the shuttle plasmid pAdTrack-CMV, with the resultant plasmid and the backbone plasmid pAdEasy-1, the homologous recombination took place in the E.Coli BJ5183 and the recombinant adenoviral plasmid was generated. The adenoviruses were packaged and amplified in the 293 cells. Then the viral titer was checked by GFP. Results  The recombinant adenovirus vector carrying p14ARF was constructed successfully. The viral titer was 2.3×109. Conclusion  The recombinant adenovirus vector could introduce p14ARF gene into the laryngeal squamous cell carcinoma line or tumor tissue effectively, which would provide experimental basis for the mechanisms and further study of the interference therapy in signal transduction of laryngeal squamous cell carcinoma.

Objective  To construct a eukaryotic co-expression plasmid pIRES-fimA:IL15, which can be used as an immunoreaction-enhancing DNA vaccine against Porphyromonas gingivalis FimA, and investigate its expression in mammalian cells.  Methods  The eukaryotic co-expression plasmid pIRES-fimA:IL15 was constructed by molecular cloning methods and characterized by restricted endonuclease mapping, PCR and DNA sequencing. The plasmid was transfected into mammalian cell CHO using Lipofectamine 2000. Expression of fimA gene was detected by Western blot and the protein secretion in cultural medium was analyzed by ELISA. Results  Endonuclease mapping showed that the target genes fimA and IL-15 obtained by PCR had the same molecular size as predicted. The DNA sequencing data also indicated that inserted fimA gene and IL-15 gene had correct DNA sequence and orientation. The recombined plasmid could express FimA in mammalian cell CHO transfected. FimA and IL-15 could be secreted into cultural supernatant detected by ELISA.  Conclusion  A new eukaryotic co-expression plasmid pIRES-fimA:IL15 was constructed and it could be applied for further immunization in animal as an effective anti-Porphyromonas gingivalis vaccine.

Objective  To observe the therapeutic effect of CDglyTK gene mediated by synthetic radiation-inducible promoter in the treatment of Tca8113 cells. Methods  CDglyTK gene in pCEA-CDglyTK was subcloned into pcDNA3.1（+） to construct plasmid pcDNA3.1（+）-CDglyTK, and then the synthetic radiation-inducible promoter in pMD18-T-E was inserted into pcDNA3.1（+）-CDglyTK to construct plasmid pcDNA3.1（+）/E-CDglyTK. The recombinant plasmid was transfected into Tca8113 cells by lipofectamine, and then exposed to 3 Gy irradiation. Cytotoxicity was evaluated by MTT. The expression of CDglyTK gene was detected by RT-PCR. The apoptosis and proliferation were examined by flow cytomtery. Results  The plasmid pcDNA3.1（+）/E-CDglyTK was constructed successfully. The comparative survival rate of Tca8113 cells was markedly decreased by induction irradiation. Up-regulation of CDglyTK expression was found in Tca8113 cells exposed to irradiation. The apoptosis index（AI） of  Tca8113 cells exposed to irradiation was higher than that of Tca8113 cells without irradiation, the other way round, the proliferation index（PI） of Tca8113 cells exposed to irradiation was lower than that of Tca8113 cells without irradiation. Conclusion  The synthetic radiation-inducible promoter can be served as a molecular switch to improve the expression of CDglyTK gene in Tca8113 cells, and low dose induction radiation can significantly improve the therapeutic efficiency.

Objective  To investigate a novel technique for new bone formation—periosteal distraction osteogenesis. Methods  A custom made periosteal distraction device was fixed to bilateral surface of the mandible in three rabbits. Periosteal distraction was performed on the left side of the mandible, the right side of the mandible served as the control. The animals were sacrificed at the end of distraction process. All the specimens were X-rayed and histologically
examinated. Results  All three animals survived with no obvious complications. Both in mass specimens and X-rays, there showed new bone formation on the distracted side of the mandible. In histological examinations, there was osteoblast-like cell infiltration and bone tissue formation in the distracted area. Conclusion  Periosteal distraction osteogenesis can provide a novel technique for the repair of bone defects.

Objective  A method for 3D-data acquisition of partially edentulous cast was introduced to lay the foundation for reconstructing 3D digital model of a partially edentulous cast and studying computer aided design（CAD） to a removable partial denture framework. Methods  Using projection system controlled by a computer, four frames of sinusoidal fringe pattern at ∏/2 intervals were projected onto the surface of partially edentulous cast consecutively within 0.4 second. Deformed fringe patterns modulated by the surface height of the cast were recorded by a digital camera. The phase value with the height information was demodulated with phase-shifting method. The transition from the unwrapped phase to the height of the points on the cast was performed with triangulation method. The multiview 3D data was integrated automatically to obtain the complete 3D profile data and the 3D digital model of the partially edentulous cast was reconstructed. Results  Dense and complete points-cloud data was achieved without scanning blind zone basically. The anatomic structure of reconstructed 3D digital model was sharp and clear. Conclusion  As an alternative for acquiring 3D data of partially edentulous cast, this method presented here with high precision and high speed meets the need for the subsequent 3D design to removable partial denture framework.