Objective To study the genetic diversity and the gene expression of membrane- bound proton- translocating ATPase（F- ATPase） subunit gene uncG derived from Streptococcus mutans（S.mutans） clinical isolates. Methods 38 S.mutans strains derived from caries- active and caries- free individuals including 18 strains displaying high acid tolerance and 20 strains displaying low acid tolerance. Gene uncG was amplified with specific primers from S.mutans genomic DNA, then the PCR product was analyzed by RFLP and sequenced. The relative expression quantity of uncG gene against the housekeeping gene recA was determined by using RT- PCR method. A gel documentation system and QUANTITY ONES software were used to analyze the data results. Results It was testified that four genotypes A, B, C and D of PCR- RFLP were revealed when respectively digested with AluⅠ and BsrⅠ , but the distributions of the four genotype strains showed no difference（P >0.05）. The differences of uncG gene transcript quantities derived from different genotype or different aciduranc strains had no significance（P>0.05）. Conclusion This study indicated that uncG gene of F- ATPase obviously displayed genetic diversity and existed polymorphism at mRNA expression level, while the AluⅠ- RFLP genotypes and the expression levels would not be responsive to different acid tolerance of S.mutans strains.

Objective To study the expression of hypoxia inducible factor- 1α（HIF- 1α）protein in buccal carcinoma and its biological significance. Methods The expression of HIF- 1α was assayed by means of immunohistochemical technique in 60 patients. The expression of HIF- 1α and its relationship with clinical pathological factors and tumor prognosis were investigated and analyzed statistically by Kruskal-Wallis Test. Results The positive rate of HIF- 1α was higher in T3- 4 than T1- 2, and the positive rate of HIF- 1α was higher in patients with cervical lymphatic metastasis than patients without cervical lymphatic metastasis. Patients with HIF- 1αover- expression had poor prognosis than patients with HIF- 1α lower expression. Conclusion Over- expression of HIF- 1α is a vital biological marker in prognosis of buccal cancer.

Objective To evaluate the effect of gilding technique on the element release from Vera Bond Ni- Cr- Be alloy exposed to artificial saliva. Methods To measure the quantity of beryllium ion which was released from common used Ni- Cr porcelain crown（controlling group）, polished Ni- Cr porcelain crown（polished group）, gilded Ni- Cr porcelain crown（gold- plating group） and gilded Ni - Cr porcelain crown prolonged 50%（gold - plating prolonged 50% group） in artificial saliva after 1 month, 3 months and 6 months by means of ICP- AES. So the effect of released beryllium ion with different treatments and the rule of different times with the same treatment were compared. Results The quantity of released beryllium ion was statistic significant among different treatments. The quantity of released beryllium ion was gradually increased with the same treatment. At the end of this experiment, it was reached the highest. The speed of released beryllium ion was gradually decreased with the same treatment. At the end of this experiment it was reached the lowest. Conclusion The gilding treatment can decrease the quantity of beryllium ion which released from Ni- Cr porcelain crown, and improve the biocompatibility.

Objective To establish an subcutaneous xenotransplanted tumor model of human ameloblastoma in nude mice. Methods Ameloblastoma cells were absorbed by primary culture, repeat attachment and pancreas proteolytic enzyme were both used to purify them. Then, the purified cells were implanted subcutaneously into the nude mice. The specimens were respectively investigated by microscope in different spots after implanting. Results Ameloblastoma cells can survive in all of the 8 nude mice. The xenograft can be found on 23 days after implanting. The rate of successful inocutation is 25%. The subcutaneously xenotransplanted tumor cells can be found with microscope in the inter - muscle tissues of nude mice. Conclusion The subcutaneously xenotransplanted tumor model of human ameloblastoma in nude mice was successfully established and it may benefit to further studies on this tumor.

Objective To compare the retention of selected cores to all- ceramic posts in post- and- core system, in which the ceramic core was combined with the post by direct sintering, adhering, and the composite resin core was formed onto the post. Methods A total of 15 all- ceramic post fabricated by alumina- zirconia nano- composite infiltrated ceramics were divided into three groups. In group A, forming and combining the ceramic core with the post by direct sintering. In group B, combining the ceramic core with the post by adhering. In group C, forming composite resin core onto the post. Each specimen was placed into a special jig along the post axis and subjected to a load on INSTRON 4302 universal testing instrument until failure. Results There was a statistically significant difference between the groups（P<0.01）. Group A showed a significantly higher retention which was 3.04 and 2.88 times as high as group B and C respectively（P<0.01）. There was no significant difference between adhering and composite resin core（P> 0.05）. Conclusion A reliable retention of the core to the post can be achieved when the alumina- zirconia nanocomposite infiltrated ceramic core is formed and combined with the post by direct sintering, which offers significantly higher retention than adhering and forming composite resin core onto the post.

Objective To observe the expression of new myoepithelial cell markers calponin and P63 in human submandibular glands. Methods Calponin and P63 antigen in routinely processed human submandibular gland tissues were immunohistochemically demonstrated by monoclonal antibodies to calponin and P63. Results Calponin expressed around all acinus and intercalated ducts as linear or punctuate pattern. Positive staining was also noted in peripheral area of some thin striated ducts that connect to intercalated ducts. Subulate or trigonal calponin expression was sometimes seen between the duct dells of striated ducts. P63 expressed mainly in the nucleus of the basal cells of excretory duct. Conclusion Calponin is an ideal marker for myoepithelial cells of human submandibular gland. P63 labels mainly the basal cells of excretory duct.

Objective To evaluate the activity of DNA polβpromoter on p53 gene in salivary adenoid cystic carcinoma（ SACC） cells. Methods The luciferase activity was examined and used to evaluate the activity of DNA polβ promoter on SACC- 83 cells. Eukaryotic expression plasmids of p53 gene were constructed and stably transfected into SACC- 83 cells. RT- PCR was used to assess the expression of p53 gene. The SACC- 83 cells were subjected to the treatments of H2O2 , ultraviolet radiation, Bleocin, and affected p53 mRNA and protein level in SACC- 83 cells were characterized with RT- PCR and Western blotting. Results The result of luciferase activity proved that the activity of DNA polβpromoter in SACC- 83 cells was much higher than that of CMV promoter. The results of RT- PCR suggested that p53 gene with different promoters were all expressed effectively, but the expression efficiency was different. It was greater in DNA polβ group than in CMV group. After DNA damage, p53 gene expression increased and DNA polβ promoter could enhance the expression of p53 gene more than CMV promoter. The results of Western blotting indicated that the expression of P53 protein between the two groups did not show any difference. Conclusion In SACC cells, the activity of DNA polβ promoter was increased and DNA polβ promoter could enhance the expression of p53.

Objective To investigate the in vitro antimicrobial activity of nano- hydroxyapatite/polyamide 66 composites （nHA- PA66） as a pulp capping agent. Methods The micro- organisims used in this study included Streptococcous mutans（S.mutans）, Lactobacillus casei（L.casei） and Actinomyces viscosus（A.viscosus）, three standard bacterial strains predominant in deep carious lesions. Agar diffusion test was used to determine the diameter of bacterial inhibition zones of nHA- PA66 compared with hydroxyapatite paste, calcium hydroxide paste and nHA- PA66 mixed with iodoform paste. Results It showed that the polymerized films and fresh paste of nHA- PA66 had no antimicrobial activity to S.mutans and very little to L.casei and A.viscosus. The antimicrobial activity of nHA- PA66 mixed with iodoform paste obviously increased, but no significant difference compared with calcium hydroxide paste. There was no antimicrobial activity of hydroxyapatite paste to the three test bacterial strains. Conclusion These findings suggest nHAPA66 used as pulp capping agent alone almost has no antimicrobial effect to the three test bacteria, but the antimicrobial activity can be increased by combining with iodoform.

Objective To investigate the effects of cyclic biaxial mechanical stimulation on adhesion of salivary adenoid cystic carcinoma（SACC）extracellular matrix（ECM）and expression of E- cadherin/cateninin complex in the SACC high metastasis cell lines ACC-M, SACC low metastasis cells line ACC- 2, we observed the functions of mechanical stimulation in the adhesion of SACC cell - ECM and investigate the mechanism in the adhesion of ACC. Methods Mechanical stimulation were applied to the cells for periods of 1, 3 and 6 hours every day, lasting for 2 days. The amplitude of mechanical stimulation applied to the cells were 1 000, 4 000 μ strain, at a frequency of 3 Hz. Unstrained cells were used as control. The expression of E- cadherin/cateninin complex on the cell of ACC-M, ACC- 2 were studied with laser scanning confocal microscope and image analysis. SACC cell- ECM adhesion was assayed by MTT technique. Results The results showed that expressions of α, β, γ- cateninin on the cell of ACC- 2 were obviously higher than that ACC-M and E- cadherin on the cell of ACC-M were obviously higher than that ACC- 2 without mechanical stimulation. Mechanical stimulation can change the expression of E- cadherin/cateninin complex on the cell of ACC- 2 and ACC-M with time. The results also showed that cell- ECM adhesion on the cell of ACC- 2 were obviously higher than that of ACC-M without mechanical stimulation. Mechanical stimulation can change the cell- ECM adhesion of ACC- 2 and ACC-M with time. Conclusion Mechanical stimulation can change the adhesion of the SACC cell- ECM and expression of E- cadherin/cateninin complex of the SACC cell. We think it played an important role in metastasis of the cancer.

Objective To investigate the effects of monofluorphosphate and αD3 on the bone mineral density of mandibular of ovariectomy rats. Methods 39 female Sprague- Dawley rats about 90 days of age were randomly divided into the following treatment groups and treated for 12 weeks: SHAM group, OVX group, MFP group, MFP +αD3 group. Rats of MFP group received monofluorphosphate by gastric feeding. Rats of MFP+αD3 group received monofluorphosphate and αD3 by gastric feeding. The femur and the mandibles were collected for histomorphometry and bone mineral density measurement. Results The bone area, bone thick, and bone mineral density of femur in the OVX group were significantly lower than those of other groups, while the trabecular separation of the OVX group was significantly higher than that of other groups. The bone mineral density of mandible was increased in OVX group and MFP+αD3 group compared with SHAM group. Conclusion Monofluorphosphate and αD3 can obviously increase the mass of mandible. The bone mineral density of femur decreased after ovariectomy while it increased in mandibular.

Objective To understand whether there were any differences of sensitivity to antifungals between the species of Saccharomyces（Candidas）isolated from oral cavity in the patients with oral candidosis and healthy volunteers. Observing the effect of nystatin topically used and discussing preliminarily the relationship between MIC and clinical effect in order to offer reference for clinical treatment. Methods The experiment was carried on 61 patients with candidosis in experimental group and 43 healthy volunteers in control group and isolates of Saccharomyces were obtained by the oral rinse technical method. To isolate and identify Saccharomyces in oral cavity by CHROMagar Saccharomyces culture medium and test the MIC of several antifungal agents such as nystatin, ketoconazole and fluconazole against Saccharomyces by NCCLSM27- A microdilution assay. 31 patients in experimental group were administered with nystatin, observing the clinical effect a week later and comparing the results with the MIC. Results ① The incidence of Saccharomyces was 78.69% and 30.23% in experimental group and control group respectively. The proportion of Saccharomyces albicans was 80.70%（experimental group） and 92.31%（control group）. ②There was no significant difference between the susceptibility of Saccharomyces albicans to fluconazole and ketoconazole（P>0.05）, but the MIC data of azole antifungals were lower than nystatin. ③The susceptibility of Saccharomyces albicans to fluconazole, ketoconazole and nystatin was 95.65%, 80.43%, and 89.13%, and a few isolates were resistent to antifungal agents. ④The effectiveness of nystatin was 87.10%, and there were a few cases which MIC differs from the clinical effect. Conclusion At present, the resistance of Saccharomyces in patients with oral fungal infection is not significant, most Saccharomyces albicans are sensitive tofluconazole, ketoconazole and nystatin. The MIC of fluconazole and ketoconazole are lower than nystatin, implying when the clinical effect of nystain is poor, to use an azole antifungal is optional. The MIC is relative to therapeutic effect to some degree, but it is not consistent completely.

Objective To investigate the prevalence of H.actinomycetemcomitans in Chinese chronic periodontitis （CP） patients and periodontally healthy adults. Methods 116 chronic periodontitis patients and 111 periodontally healthy adults were included. In each CP patient, subgingival plaque samples were collected from two sites of different molars with the greatest probing depth（PD）and one periodontally healthy site（PD≤3mm）. The samples of periodontally healthy adults were obtained from the mesio- buccal site of one first upper molar. Bacteria DNA were extracted for detection of H.actinomycetemcomitans by 16S rRNA PCR. Results The prevalence for H.actinomycetemcomitans of diseased sites（33.62%）was significantly higher than that of healthy sites from CP patients（0.86%）and the periodontally sites（0.90%）（P<0.01）. No significant difference was observed between male and female CP patients（P>0.05）. A decreasing trend of H.actinomycetemcomitans was observed as the age increased. And the pocket depth and clinical attachment losswas associated with the occurrence of H.actinomycetemcomitans in a positive mode. And H.actinomycetemcomi - tans was more often detected in the bleeding sites on probing. Conclusion H.actinomycetemcomitans was more frequently detected in periodontitis sites than periodontally healthy sites. For CP patients, a higher prevalence was associated with the seriously involved sites than those moderate and mild implicated sites. H.actinomycetemcomitans is considered to be the one of the periopathogens involved in the etiology of chronic periodontitis.

Objective The aim of this study was to investigate the prevalence of T.forsythensis in Chinese chronic periodontitis patients, and correlate it with clinical parameters. Methods 108 chronic periodontitis patients were selected according to clinical criteria. In each patient, subgingival plaque samples were collected from two of the periodontitis involved molar sites with the deepest periodontal pocket depth（diseased sites）and one healthy gingival sulcus （healthy sites）. T.forsythensis was detected by 16S rRNA polymerase chain reaction. Clinical assessments including probing depth, clinical attachment loss and bleeding on probing, were made at sampling sites. Results The prevalence of T.forsythensis in diseased sites and healthy sites was 59.72% and 3.70% respectively（P <0.001）. The prevalence of T.forsythensis was significantly higher in deeper pockets and more serious clinical attachment loss, Spearman rank correlation coefficient was 0.48 and 0.51 respectively. The prevalence of T.forsythensis in BOP （+）sites was 61.31%, and in BOP（- ） sites was 8.80%（P<0.001）. Conclusion The prevalence of T.forsythensis was significantly correlated with clinical parameters, suggesting that T.forsythensis is closely related to chronic periodontitis in the Chinese population.

Objective To compare craniofacial structural characteristic of syndromic and non- syndromic patients with cleft palate and to probe into the reason of their maxillary hypoplasia and to lay a foundation for better treatment protocol for syndromic patients with cleft palate. Methods The sample consisted of 8 individuals with Treacher Collin syndrome, 9 patients with Pierre Robin syndrome, and 40 patients with non- syndromic cleft palate which met certain criterions. Lateral cephalometric radiographs were obtained from each study subject. A total of 18 variables, comprising 9 angular, 7 linear, and 2 ratio measurements, were studied. SPSS 12.0 software was used to describe the statistics data, consisting of means, SD, and t test. Results The tendency for smaller value in SNB and larger value in ANB indicate a severer anteroposterior mandibular hypoplasia in the syndromic type cleft. There was no difference between syndromic and non- syndromic cleft palate patients with regards to maxillary anteroposterior development. No significant difference on the development in cranial base area was found either. Conclusion This interplay of cranio- facial bones is very important in the development of this complex, which will not only affect the growth but also the defect development. In this study, the patients with the two syndromes showed the similar growth potential of maxilla with the non- syndromic cleft patients.

Objective To investigate the relation between different extents of cleft malformation with the speech characteristics in patients with cleft palate. Methods The formant frequency of vowel [i] of 46 incomplete cleft palate patients（ICCP group） and 56 complete cleft palate patients（CCP group） before and after cleft palate repair, as well as 30 normal people（C group）, were measured and analyzed on spectrogram. Results The comparison of F1 between C group and CCP, ICCP before surgery showed no difference. So did the comparison of F1 between C group and CCP, ICCP after surgery. The comparison of F2 between C group and CCP, ICCP before surgery showed significant difference. The value of the C group was the highest. The value of the ICCP was higher than that of CCP. So did the comparison of F2 between C group and CCP, ICCP after surgery. The comparison of F3 between C group and CCP, ICCP（including before and after surgery）was similar to the results of F2 between the three groups. The comparison of F1 between before and after surgery in ICCP group showed no difference. However, the same kind of comparison of F2 and F3 showed significant differences: Both the values after surgery were higher than those before surgery. The comparison of F1, F2 and F3 between before and after surgery in CCP group was similar to that in ICCP group. Conclusion The extent of the cleft malformation is closely related to the status of the speech in patients with cleft palate. With the malformation more severe, the tongue will move backward more obviously, the elevation of the soft palate after cleft palate repair will be less active. Two ways are recommended for those patients with CCP: ①Early interceptive orthodontic treatment to reduce the extent of palate malformation; ②The hard palate repair can be performed prior to the soft palate repair. Patients with severe cleft lip and palate can have hard palate repaired while accepting the early cleft lip repair.

Objective To summarize the surgical treatment effects of dislocation sagittal fracture of the mandibular condyle （DSFMC）. Methods Twenty- two cases of DSFMC were classified according to the fracture location and treated with surgery. The clinical and radiographic outcomes were contrasted before and after treatment. Results ① There were 18%, 57% and 25% cases of type Ⅰ, type Ⅱ and type Ⅲ DSFMC respectively. ②For type ⅠDSFMC, dislocation part of condyle was removed. For type Ⅱ DSFMC, nine dislocation parts of condyles were free grafting and rigid fixation, and five dislocation parts of condyles were removed. The whole condyle was resected because of ankylosis of TMJ in two cases. For type Ⅲ DSFMC, dislocation part was free grafting and rigid fixation in five condyles. The whole condyle was removed in two cases due to comminuted DSFMC. ③Postoperative mouth opening and mouth opening deviation were 33.9 mm and 1.5 mm respectively 6 months after the surgical treatment. There were significant improvement on mouth opening and mouth opening deviation than those before the surgical treatment（P<0.05）. Normal occluding relation was resumed in 17 cases. With occlusal adjustment, occluding relation was resumed also for those 5 cases that showed 1- 2 mm open bite. ④There was no postoperative evidence of condylar resorption and plate distortion. Conclusion Surgical treatment is an effective way for DSFMC. Mouth opening and mouth opening deviation can be improved significantly after surgical treatment. After surgical treatment, DSFMC can resume normal occlusal relation also. There is no significant condylar resorption after free grafting.

Objective To evaluate the associations between periodontal conditions, serum level of interleukin- 1β （IL- 1β） and delivery outcomes in pregnant women with a diagnosis of threatened premature labor（TPL）. Methods Eighty systemically healthy pregnant women were enrolled in the study. The case group was composed of 40 pregnant  women hospitalized with the diagnosis of TPL（TPL group） and the control group was composed of 40 normal pregnant women（Non - TPL group）.  eriodontal examinations included assessments of plaque index（PLI）, clinical attachment loss（CAL）, probing depth（PD）, bleeding index（BI） and the percent of periodontitis sites（PD>3 mm, CAL≥2 mm）. The serum level of IL- 1βwas determined using commercially available enzyme- linked immunoassays. Results ①Fourteen of forty subjects of TPL group delivered premature labor infants（TPL- TB group）, and twentysix subjects delivered natural labor infants（TPL- PB group）. No infants were delivered as premature labor infants in non- TPL group. There were significant differences in gestational age at delivery, birth weight, PLI, percentage of periodontitis sites and IL- 1β levels between the non- TPL group and TPL group or between the TPL- TB group and TPL- PB group（P<0.05）. ②Significant negative correlation were observed between the gestational age at delivery and percentage of periodontitis sites as well as serum IL- 1β levels（P<0.05）. And significant positive correlation were observed between percentage of periodontitis site and serum IL- 1β levels（P<0.05）. Conclusion Periodontal in -flammation might be one of the pathogenesis of preterm birth.

Objective To assess the clinical and histological features and therapeutic efficacy of 30 cases of malignant sublingual salivary gland tumors. Methods The clinicopathologic data of 30 patients with malignant sublingual salivary gland tumor were obtained from West China Hospital of Stomatology, Sichuan University from 1955 to 2005. Results There were 18 male and 12 female, and the average age of patients was 50.6 years old. Seventeen cases were adenoid cystic carcinoma, accounting for 56.7%. There were 17 cases clinically staged as Ⅲ, accounting for 56.7%. Distant metastasis and tumor recurrence were the main death reasons. The overall local recurrence rate was 30.0%, and distant metastasis rate was 26.7%. Conclusion Sublingual gland malignant tumors are rare and most of them are adenoid cystic carcinoma. Surgery is the main treatment option. The resection of the tumor accompanying with the neck dissection is the key method to achieve good therapeutic effect. The postoperative radiotherapy and chemotherapy should be adjuvant.

Objective To study the characters of the diagnosis and treatment for midfacial fractures with orbital floor fractures. Methods 136 cases of midfacial fractures with orbital floor fractures were diagnosed and treated. All patients underwent CT scans and accepted surgical intervention. Orbital floor fracture was restituted in 49 cases. Orbital floor defects were reconstructed with autogenous bone, titanium mesh or porous polyethylene implant（Medpor）in 21 cases. Results 136 cases recovered well，their facial appearance and function were improved significantly. There were no severe complications happened postoperatively in all cases. 2 cases had postoperative wounds infection and 1 case had temporary ablepsia, but healed completely. Conclusion CT is the best method for diagnosing orbital floor fractures. The objective of treatment is restoration of normal orbital floor and orbital capacity, the reduction of orbital contents prolapsed and reconstruction of orbital floor fractures with repair materials.

Objective To evaluate the clinical prosthetic effect of IPS- Empress 2 pressable ceramic crowns. Methods 198 teeth of 70 patients were restored with IPS- Empress 2 pressable ceramic crowns. The patients were asked to return in one week and every half year. The clinical prosthetic effect was evaluated. Results Through follow- up of 3- 38 months, the veneer porcelain crowns of 3 teeth were broken. 2 crowns fall off due to teeth fracture, gingivitis occurred in 2 teeth, pulpitis or periapical periodontitis occurred in 3 teeth. The shades of 3 crowns were darkening. The prosthetic effect of 185 teeth was satisfied. The rate of satisfaction was 93.4%. Conclusion IPSEmpress 2 pressable all- ceramic crown has the advantages of aesthetic effect, good biocompatibility and simple fabrication. But its strength is not enough for posterior teeth and it can not cover the deep color of non- vital teeth and metal materials.

Objective To explore the main point of nursing acquired immune deficiency syndrome（AIDS） pa - tients with oral lesions. Methods To analyze and to summarize nursing experience through 2 patients suffering from AIDS with oral lesions. Results 2 AIDS patients changed for the better through disinfection isolation, oral nursing, psychology nursing and education propaganda. Conclusion The standard nursing skills is important to AIDS patients, doctors and nurses.

Objective To study the biological properties of human dental pulp cells（HDPC）by cloning and analysis of genes differentially expressed in HDPC in comparison with human gingival fibroblasts（HGF）. Methods HDPC and HGF were cultured and identified by immunocytochemistry. HPDC and HGF subtractive cDNA library was estab - lished by PCR- based modified subtractive hybridization, genes differentially expressed by HPDC were cloned, se - quenced and compared to find homogeneous sequence in GenBank by BLAST. Results Cloning and sequencing analysis indicate 12 genes differentially expressed were obtained, in which two were unknown genes. Among the 10 known genes, 4 were related to signal transduction, 2 were related to trans-membrane transportation（both cell membrane and nuclear membrane）, and 2 were related to RNA splicing mechanisms. Conclusion The biological properties of HPDC are determined by the differential expression of some genes and the growth and differentiation of HPDC are associated to the dynamic protein synthesis and secretion activities of the cell.

Objective To analyze influential factors of cultural method of human oral mucosal epithelial cells （hOMEC）and to establish a reliable cell culture system for hOMEC. Methods Benzalkonium bromide and gentamicin sulfate were used to prevent microbial contamination. Separations of epithelium from underlying connective tissues with Dispase at different concentration were compared. Enzyme digestion was used to isolate cells and ker - atinocyte- serum free medium（K- SFM）was employed for primary culture and subculture of hOMEC. Results Microbial contamination was under control. Separation of epithelium from underlying connective tissues with 0.40% Dispase was more complete than that of 0.25% Dispase. The cells grew fast and well in vitro. Conclusion The high successful culture of hOMEC and simplified procedures could be obtained with improvement of methods.

Objective To build a digital visible model of the mandible in order to provide morphological data for image diagnosis and operation of mandible diseases. Methods A male adult cadaver specimen was taken for the purpose of study. A digital human databank was got after fixation, perfusion, refrigeration, embedding, section and photograph of the specimen. The thickness of each layer was 0.1 mm. To select mandible image data from chin to condyle and to draw an outline of mandible and teeth image of each layer in 2D Adobe photoshop 8.0. Finally, reconstruct 3D model of mandible was set up in Amira reconstruction software. Results A 3D model of mandible was formed accurately using of digital human data. The model was fine, visible and displayed cross - section image of mandible. The anatomical shape of mandible and mandibular teeth were vividly reappeared in three- dimension. The location and trend of mandibular nerve canal were clearly appeared in the transparent model of mandible. The model could be revolved in 3D. Conclusion The study got a complete and exact cross- section data. The visualization of mandible can be realized in Amira reconstruction software. The reconstituted organs can be recovered to the natural state.

Objective To evaluate the applicability and effectiveness of reconstruction of mandibular condyle by transport distraction osteogenesis in an animal model of rhesus monkeys. Methods Six adult rhesus monkeys were used in this study. Bilateral condyles and articular discs were extirpated, and the technique of transport distraction osteogenesis was performed to reconstruct the condyle. X- ray and CT scanning films were taken at various intervals. Two monkeys selected at random were sacrificed respectively at 4, 12 and 24 weeks after completion of distraction, and the newly formed condyles resulted from bony transport disc were harvested and processed for histologic examination. The removed condyles at surgery were used as normal control and prepared in the same manner. Results Open bite was seen in all animals postoperatively, and disappeared at the end of distraction. The shape and appearance of the bony transport disc was similar to original condyles at sacrifice. The articular cavity was filled with fibrous connective tissue and considerable cartilage cells were observed in the surface of the condyle stump. Bone regeneration was perfect in the distraction gap. Conclusion A neocondyle with functional shape can be created by transport distraction osteogenesis, which suggested that this technique might be an alternative method in reconstruction of the condyle.

Objective To observe the morphologic changes of inferior alveolar nerve before and after osteocompression on dog′s mandible. Methods 8 dogs were selected and divided into 4 groups, 2 dogs per group. The osteocompressor was fixed on the right buccal side of the mandibule. Crew the compressor to compress the mandible 1.0 mm per 3 days for totally 15 days. On the 1st day, 15th day, 45th day and 90th day after osteocompression, the dogs of different groups were killed respectively. Get the inferior alveolar nerve and HE staining was carried on. Results ①On the 1st, 15th and 45th day after osteocompression, the fiber of the inferior alveolar nerve was obviously injured. ②On the 90th day after osteocompression, the injured nerve was almost recovered to normal. Conclusion The osteocompression could cause temporary injury on the inferior alveolar nerve, but the injury was reversible and might recovere by times after osteocompression.

Objective To assess the effect of the thickness of periodontal ligament on the fracture resistance of root and post- core system. Methods Forty- five simulated roots in the same length, taper and diameter were made of polymethacrylate（PMMA）. Then the wax patterns of post- cores were cast. Soft lining material was used to simulated periodontal ligament. And each specimen was embedded in acrylic resin and then fixed in a special jig on the universal load- testing machine. A compressive load was applied at a 90- degree angle to the long axis of the core until fracture, at a crosshead speed of 1 mm/min. The maximum of load and the displacement were recorded. Results The mean values of load in root and post- core system were 148.033 N、161.889 N、168.667 N、181.589 N、194.622 N, and the mean values of displacement were 1.965 mm、2.837 mm、3.327 mm、3.927 mm、5.326 mm. Conclusion The fracture resistance and displacement of root and post- core system with the same quality and altitude periodontal ligament are associated with the thickness of periodontal ligament when the range of thickness is from 0.2 mm to
1.0 mm.

Objective To investigate the anti- proliferation effect of tyrosine protein kinase inhibitor, Genistein, on human salivary adenoid cystic carcinoma cell line SACC - 83, and its effect on Survivin expression. Methods SACC- 83 cells were treated with different concentration Genistein for different time, cell survival rate was calculated with MTT assay, apoptosis was detected with flow cytometry, the expression of Survivin was quantitatively analyzed by Western blotting and FluorChem V2.0 software. Results When treated with Genistein of certain concentration for certain time, SACC- 83 cell growth was significantly inhibited. With the increase of concentration and elongation of acting time, the inhibitory effects increase. Treated with 220 μmol/L Genistein for 72 hours, SACC- 83 cell growth was significantly inhibited, cell apoptosis was induced（P<0.01）, and the expression of Survivin decreased. Conclusion Genistein inhibits the growth of human salivary adenoid cystic carcinoma cell line SACC- 83, and induces cell apoptosis; the decrease of Survivin expression may be one of the mechanisms of Genistein inducing apoptosis.

There are many therapies to treat the trismus, such as durg therapy, occulusal splints, pulsing electromagnetic fields, medical iontophoresis, laser, acupuncture. But there are no objective criterias about the most effective methods. The patient with trismus after extraction was cured by using comprehensive rehabilitation including physical therapy（ultrashort wave electrotherapy, medical iontophoresis, middle frequency electrical therapy）, traditional Chinese manipulation, functional training, muscular and joints traction. The patient recovered completely with satisfactory. Thus this method had the advantage of painless, noninvasive and non- stimulation with well clinical practice.