Objective　To study the effect of angiogenesis inhibitor and its combine with chemical drug in suppressing the growth of adenoid cystic carcinoma (ACC).Methods　Acc-M cellswere inoculated subcutaneous into BABL/C nu/nu mice. The mice were divided into control, different dose of TNP-470 treatment groups, 5-Fu treatment group and TNP-470 plus 5-Fu treat- ment group. Treatments were given 48 hours after inoculation. The mice were sacrificed on the 22nd day and excised tumors were weighted. Tumors were also investigated by immunohistochemistry and ultrastructural observations.Results　TNP-470 100 mg/kg/qod efficiently inhibited the growth of Acc-Mtumors. TNP-470 30 mg/kg/qod combined with 50 mg/kg/week 5-Fu also resulted in significant growth inhibit of the tumors. TNP-470 suppressed tumor growth by inhibiting neovascularization, therefore inducing apoptosis of Acc-M cells. All experimental groups had different degrees of VEGF and bFGF express.Conclusion　Since ACC is a slow developing tumor, blood supply is not so sufficient as sarcomas. Angiogensis inhibitormay inhibit its growth in high dosage. Combining medium dosage of angiogensis inhibitor with chemical drug may have synergistic result in inhibiting ACC growth.

Objective　The purpose of this study was to investigate the changes of basic fibroblast growth factor (bFGF) ex- pressed in normal human dental pulp at different root development stages of permanent teeth.Methods　Based on the teeth root development status, the pulp tissues were classified into three groups: root just starting development, being in development and apical closed. The pulps were immunohistochemically examined by use of bFGF antibody.Results　Stainingwas strongly positive in immature permanentteeth, especially atthe stage of root just starting development. Image analysis indicated thatthe gray values of positive reaction in three groups were statistically different (P<0.001). For the first group, the gray value of the outer pulp was higher than that of the pulp core. For the second group, the pulp core has a higher gray value in the coronal pulp, while a lower value in root pulp compared tothe outer pulp.Conclusion　Withthe development of root formation, the expression of bFGF in dental pulp shows different characteristics. bFGF may play a role in dental pulp development and maturation.

Objective　In order to determine the effect of factors pertaining to the development and metabolism of periodontal ligament, the author investigated the interaction between osteoblasts and fibroblasts.Methods　The cell co-culture model was es- tablished by cell culture inserts. The expression difference of protein related to mineralization (ALP, TypeⅠcollagen ) between these two kinds of cells cultured individually and co-cultured were evaluated.Results　Co-culture changed the ALPase activity of the two kinds of cells greatly .The ALP expression of osteoblasts decreased, but the ALP expression of periodontal ligament fibro- blasts incresed. The Col-Ⅰexpression of these two kinds of cells did not change significantlywhen theywere co-cultured.Conclu- sion　Periodontal ligament fibroblast could restrain the osteogenesis function of osteoblast, while osteoblast could induce the dif- ferentiation of fibroblast when both of them existed in periodontal tissue.

bjective　In this experiment, genes sensitive to mechanical stretch in osteoblast like cells were cloned through
substractive hybridization technique.Methods　Two dimensional mechanical stretch with deformation of 12% and frequency of 6
cycles was loaded on human osteoblastic like cell line Saos-2. Complementary deoxyribornucleic acid (cDNA) library of cells was
constructed 12 h after loading, acting as tester. cDNA library of cells without loading was constructed, acting as driver. A sub-
tractive cDNA library osteoblastic like cell stimulated with mechanical stretch was constructed through substractive hybridization
technique.Results　Of clones randomly selected from this library, fifteen genes were identified to be the differentially expressed
genes. Comparing with the sequences published in GeneBank via Internet, two sequences located in chromosome 9 and 18 respec-
tively were identified to be novel, whichwere named as stretch sensitive gene 1 and stretch sensitive gene 2.Conclusion　It is an
efficient approach to clone and study genes relative to mechanical stretch through substractive hybridization technique.

Objective　To evaluate the effect of stretch on sarco(endo)plasmic reticulum Ca2+-Mg2+ATPases activity and mR- NA level and study the remodeling reaction of muscle in a variety of mechanical environments.Methods　Myoblast from maxillo- facial skeletal muscle of one-week-old male Sprague-Dawley ratwas cultured and stretched cyclicly using a four-point bend device. Inorganic Phosphorus test was used to compare the activity of Ca2+-Mg2+ATPases of myoblast before and after stretch. RT-PCR was also used to observe the Ca2+-Mg2+ATPases mRNA level.Results　The activity of Ca2+-Mg2+ATPases of myoblast down regulated significantly in 4 hours. During the period of 8 hours to 24 hours, up-regulation followed then returned to control level at the 48 hour point. RT-PCR showed that Ca2+-Mg2+ATPases mRNA level were elevated by stretch, particularly at 2 hour and 48 hour point.Conclusion　The results suggested a transcriptional control of Ca2+-Mg2+ATPases activitywas involved in the muscle remodeling process induced by stretch.

Objective　Purpose of the studywas to investigate the content ofNickel(Ni) and Chromium(Cr) ion in gingival tis- sue and blood, and to discuss the reason of gray line in gingival afterwearing non-noble Porcelain-Fused-to-Metal crown.Methods 　38 rabbits were selected as experimental animals which were divided into three groups: control group, group 1(3 months) and group 2( 6 months ). The content of Ni and Cr ion in gingival tissue and blood was detected by atomic absorption spectrometer. Results　The amount of Ni and Cr in group 2 was significantly higher than that in other groups (P<0.05). There was no differ- ence between group 1 and control group (P>0.05).Conclusion　The reason of gingival colouration might be the electrochemical corrosion. The metal ion was released in gingival tissue and blood.

Objective　To study the best parameter of impulse Nd:YAG Laser-aided debracket.Methods　To measure the bonding strength of ceramic bracket and pulp cavity temperature after different laser energy. First group was not irradiated by la- ser, second groupwas irradiated by laser of power5W and irradiating duration 2s, third groupwas power3W and duration 3s, and fourthgroup was power 2W and duration 5s.Results　There were significant differences of bonding strength among the four groups. The bonding strength of ceramic bracketwas significantly reduced by laser irradiating. Therewere significant differences of the pulp cavity temperature increasing among different laser power irradiating groups. The lowest temperature increasing(3.65℃) groupwas the group of laser power 3W and irradiating duration 3s.Conclusion　The bonding strength of ceramic bracketswas sta- tistically reduced after laser irradiation and the best parameter of impulse Nd:YAGLaser-aided debracket is laser power3W and ir- radiating duration 3s.

Objective　To compare the efficacy of 2 available periodontal systems for local delivery of antibiotics.Methods　26 teeth with moderate to severe periodontitis (PD≥4 mm) from 11 patientswere selected. The teethwere randomly divided into test group and control group. Periocline (2% minocycline hydrochoride ointment) was applied tothe teeth in the test group, while Ya- kang (local metronidazole) was applied in the control group. The data including clinical indices and microbiological parameters was collected before and on the 7th, 14thday after the therapy.Results　Before treatment, the mean of each clinical indices and microbiological parameters between the two groups was not different (P>0.05). But both groups demonstrated significant differ- ences with control after treatment (P<0.05), while there were no significant differences between the two test groups (P>0. 05).Conclusion　Both Periocline and Yakang were effective and secure local delivery drug for treating periodontitis.

Objective　It has been demonstrated thatwhen a high-speed handpiece stops rotating, negative pressure will form. Thus, contaminating fluid inwhichthere are many kinds of bacteria and viruses fromthe external environmentwill retract into vari- ous compartments of the handpiece and the dental unit. The purpose of the study is to compare the preventing effect of antisuction designed handpiece and conventional handpiece on viral contamination at different rotating times.Methods　Twenty handpieces with or without antisuction device (10 of each) were used in the study. Each handpiecewas submerged into 10-6μg/μlHBVpar- ticle solution rotating 5 and 10 times respectively (every time rotating for 10 seconds). Samples were obtained from the water line and chip air line of the handpieces and examined by RT-PCR.Results　At the same rotating times, there was statistical signifi- cance of the viral concentration between the two kinds of handpieces (P<0.05). However, therewas no statistical significance of the viral concentration between different rotating times in each group (P>0.05).Conclusion　Contamination taking place in both water and air lines of dental handpiecewas not enhanced by increasingthe number of rotatingtimes of the handpiece. The an- tisuction devices installed into the water line and chip air line were demonstrated to prevent viral contamination effectively.

Objective　The aim of this studywas to evaluate the aesthetic effectiveness of implant supported dentures in partial- ly edentulous patients and the patients′satisfaction on aesthetic effectiveness.Methods　The aesthetic status of peri-implant gingi- val and the correlated soft tissue health of implant supported dentureswere investigated. The questionnaire of the patients′satisfac- tion on aesthetic effectiveness had also been collected.Results　43 interdental papillae of 22 restorations were investigated, 53. 4% of which were optimal. And the size of interdental papillae increased during the period of study, which had no relationship with plaque and gingival inflammation. The patients were satisfied with the esthetic effectiveness of implant supported dentures. Conclusion　To some extent, the interdental papillae has regeneration ability, but there are no close relationship between regen- eration and gingival inflammation. In order to acquire more aesthetic effectiveness, surgical and nonsurgical techniques should be used by clinicians.

Objective　To investigate the changes of occlusal relationship in posterior teeth among the pre-treatment, post- treatment, and to analyze some possible factorswhichmay relate tothe relapse of posterior occlusal relationship.Methods　29 fin- ishing ClassⅡdivision 1 cases treated by extractionwith full records selected were included. The sample consists of 12 males,17 females. The follow-up lateral head films and study castswere taken at least 2 years after orthodontic treatment. The cephalograms were measured by computerized program and the study casts measured by caliper.Results　Improvements of molar relationship were shown during treatment and a little bit changes during follow-up. During the treatment, the amount of mesial movement of the lower molars was more than the uppermolars in dental ClassⅡmalocclusion and the amountwas similar between upper and lower molars in skeletal ClassⅡmalocclusion although the ANB angle decreased significantly. During the follow-up stage, the move- ment tendency between upper and lowermolarswas reverse. The sagittal growth pattern of mandible and Irregularity of upper inci- sors were nearly correlatedwiththe relapse ofmolar relationship.Conclusion　The stability ofmolar relationship is acceptable dur- ing the follow-up stage in ClassⅡmalocclusion. The improvement of molar relationship depends on the difference of mesial move- ments between upper and lower molars in dental ClassⅡmalocclusion. However, in skeletal ClassⅡmalocclusion the improve- ment of jaw relationship does the effect. The positive growth of mandible and crowding of upper incisors may affect the relapse of molar relationship.

Objective　To study the bone anatomic structure of the temporal bone region and provide reference in implant sur- gery in this region.Methods　Manual quantitative measurements of the bone structure were performed in 73 skull specimens(38 from male and 35 from female).Results　In the area of 8∶00~11∶00(right ear)and 16~22 mm from center of the external au- ditory canal in the temporal bone region, the minimum bone thickness is as follows: 11∶00:6.77 mm in male,5.18 mm in fe- male; 10∶00:8.60 mm in male,6.77 mm in female; 9∶00:9.85 mm in male,7.30 mm in female; 8∶00:14.50 mm in male, 10.80 mm in female.Conclusion　①In the temporal bone region,the area of 8∶00~11∶00(right ear)and 16~22 mm from cen- ter of the external auditory canal offers sufficient bone for implants. The length of implants should be as follows: 11∶00:4~5 mm in male,3~4 mm in female; 10∶00:4~7 mm inmale,4~5 mm in female; 9∶00:4~8 mm inmale,4~6 mm in female; 8∶00: 4~12 mm inmale,4~8 mm in female.②Towards the external auditory canal and from12∶00 to 11∶00, 10∶00 to 8∶00,the bone became thicker, so,if no ample bone is available in the initial site,the location should be shifted anti-clockwise in right side (clockwise in left side) and closer to the external auditory canal.③The differences between male and female are statistically sig- nificant in the temporal bone region,so they should be treated distinguishingly during the clinical practices.

Objective　To assess the effectiveness and reliability of free flap transferfortreatingthe advanced osteoradionecrosis (ORN)of mandible.Methods　Eleven cases of free flap transfer for treating the advanced ORN of mandible from October 1999 to February 2003 were reviewed. Data concerning the operation included site, stage and histology of primary tumor, dosage of radio- therapy, defect description, design of free flap, recipient vessel, free flap survival and complications.Results　There were 8 males and 3 females, with age ranged 29-65 years old. Fifteen free flaps were used for reconstructing the defects, 12 were fibula flap, 2 were rectus abdominismyocutaneous flap, and 1 was radial forearmflap. All the free flaps survived completelywithout par- tial or total necrosis. The complication rate was 36.4%. All patients had complete resolution of ORN symptoms. No evidence of ORNrecurrencewas observed in any patient.Conclusion　Free flap transfer provides a reliable and effective means fortreatingthe advanced ORN of mandible. Free fibula flap is the workhorse flap for reconstruction of mandible.

Objective　To determine the level of hyaluronic acid (HA) in serum of patients with oral and maxillofacial malig- nancy and to investigate the correlation between the levels of serumHA and stage of the malignant lesions and treatment response. Methods　44 patientswith oral and maxillofacial malignancywere analyzed and 24 healthy individuals served as controls. Venous blood was collected fromthe patients before treatment and the healthy individuals. One week aftertherapy, venous bloodwere col- lected in 24 patients once again. Serum levels ofHAwere measured with quantitative radioimmunoassay (RIA).Results　Before treatment, the serumHA concentration in patients with oral and maxillofacial malignancy was significantly higher than that of the controls(P<0.05). Also, the serumHA concentration in patientswith OSCCwas significantly higher than that of the controls(P <0.05). No difference was noted in serum HA concentration between patients with salivary ACC and the control group (P> 0·05). The serumHA concentration of patients in stageⅢandⅣwas significantly higherthan that of patients in stageⅠandⅡ (P<0·05). SerumHAlevels decreased in patients after a complete treatment, butthe differencewas not significant(P>0·05). Conclusion　Serum levels of HAmay be useful in diagnosis of OSCC and was associated with clinical stages in patients with oral and maxillofacial malignancy. However, it may not be contributory to monitoring treatment response in patientswith oral and max- illofacial malignancy.

Objective　To observe the effect of clinical therapy of using six flavor glutinous rehmannis pill on chronic adult pe- riodontal inflammation.Methods　120 adult patientswho have been cured fortheir periodontitiswere selected and divided into two groups randomly. Control group was only treated with SRP(scaling and root planning), and test group was requested to take six flavor glutinous rehmannis pills orally for 5 months after SRP.Results　Aftertaking the medicine for 5 months, RPD (reduction in probing depth) was 0.43 mm, GAL(gain in attachment level) was 0.22 mm and was quite different from the control group(P< 0.01).Conclusion　SRPtogetherwith six flavor glutinous rehmannis pill is betterthan pure SRP in RPD and GAL, it is one kind of taking medicine for improving resistibility and maintenance therapy.

Objective　To study the role of Ca2+overload and energy metabolism in mitochondria in masticatory muscle dys- functional induced by occlusal trauma.Methods　Mitochondrial Ca2+contents were measured with atomic emission spectropho- tometer. Mitochondrial ATP and ADP contents were measured with high performance liquid chromatography.Results　①Mito- chondrial Ca2+contents of masseter muscle ipsilateral to mental splint in ten and twenty days′experimental groups and that con- tralateral to mental splint in twenty days′experimental group increased significantly (P<0.05).②Mitochondrial ATP contents of masseter muscle ipsilateral tomental splint in experimental groupswere higherthan that in control groups and contralateral tomen- tal splint after twenty days.③Mitochondrial Ca2+contents of masseter muscle ipsilateral to mental splint were significantly nega- tively correlated tothe mitochondrial ATP contents(r=-0.780,P<0.05).Conclusion　Ca2+overload inmitochondria depress- es ATP production, which results in energy metabolism disorder in masticatory muscle cells. It may play an important role in the mechanism that occlusal trauma results in masticatory muscle dysfunction.

Objective　To study the mechanical properties of two kinds of composite resins reinforced by preimpregnated glass fibers.Methods　Sinfony and belleGlass composite resinswere used tomake standard samples (25 mm×2 mm×2 mm) with and without glass fibers. After all specimenswere stored for24 hours in distilledwater at (37±1)℃, the flexural strength and flexural modulus were measured on a universal test machine.Results　Both flexural strength and flexural modulus of Sinfony composite re- inforced by the glass fibers became significantly increased, whichwere (555.76±67.31) MPa and (12.59±3.06) GPa respec- tively, and 4.5 and 2.5 times muchmore than those of the specimenswithout glass fibers (P=0); the flexural modulus of belle- Glass composite became significantly increased, which was (14.10±2.88) GPa, and 0.9 time much more than the specimens without glass fibers (P=0), butthe improvement of flexural strengthwas not significantly.Conclusion　Glass fibers can improve the mechanical properties of composite resins, but the reinforcement effect is different between different resins.

Objective　Quantitative study of the effect of anti-human VEGF mAb E11to VEGF level in serum of nude mice transplanted buccal carcinoma.Methods　E11was administered into BALB/c nu/nu mice which were transplanted human buccal carcinoma. The saline was administrated as negative control. Mice were killed at 18 days. The VEGF level in serum of mice was determined by improved indirect ELSIA.Results　Comparedwiththe VEGF level in serum ofmice in saline group, itwas dramat- ically decrease in E11group. The VEGF level in serum of mice treated E11by subcutaneouswas lowest and only reached (1.17± 0.13)μg/L.Conclusion　It demonstrated that the anti-human VEGF mAb could reduce the VEGF level in serum by binding VEGF, and block its biological activity. It indicates that VEGF in serum of malignant tumor patient is a new tumor marker.

Objective　To evaluate the clinical performance of the two configurations of gingival margin preparation of tooth. Methods　The cases in this study were divided into two groups according to different tooth defects. Each group consisted of 40 cases. One group′s gingival margin configurationwas 90°shoulder, the otherwas under-gingival non-shoulder. The clinical perfor- mance of these restorationswas followed up for 1 year and 2 years. The evaluators examined the restorations for plaque index, gin- gival index, marginal discolor and marginal fit.Results　There was no significant difference in the evaluators between the two groups.Conclusion　The under-gingival non-shouldermargin configuration of porcelain fused to mental should be used for clinical application compared with the 90°shoulder one in certain circumstance.

Objective　To discuss the function ofMMP-9,MMP-2 in the remodeling bone tissue around implant during unload- ed period.Methods　At the anterior of the maxilla and mandibular of the Beagle dog, implants were placed at different periods, so the implant specimens of different periods were obtained after dogs were killed. The implant specimens were removed, fixed in 4% prarformaldehyde for 24 hours at 4℃, decalcifiedwith 10% EDTA at pH7.2, embedded in paraffinwax and sectioned. The observation of the expression changes of theMMP-2, MMP-9 in the milien bone tissue of the implant at different periodswere taken by immunohistochemical staining.Results　Matrix metalloprotainase (MMP-9) was mostly expressed at the peripheral cytoplasmic of osteoclast, macrophage, lining cell and fibroblast. MMP-2 was mostly expressed at the peripheral cytoplasmic of osteoblast, fi- broblast, some osteoclast also expressed this enzyme.Conclusion　MMP-2 and MMP-9 have an important function at the injured bone absorption, healing and bone remodeling after dental implant placement.

Objective　To observe osteoclasts on the resorbing surface of human deciduous teeth.Methods　After fixing the collected deciduous teeth, we prepared the tooth sliceswithout decalcification, treated themwithHE andTRAP dyestuff, and ob- served the osteoclasts under light and scanning electronmicroscope.Results　Therewere large quantity of various forms of overlap- ping and huge osteoclastswith many nuclei and silk-like protuberances on the resorbing surface of deciduous teeth. The multinu- cleated osteoclasts align on the surface of coarse dentin.Conclusion　On the resorbing surface of human deciduous teeth there are large amount of osteoclasts which can be used as a source of studying human osteoclast.

Objective　The aim of this study was to observe the expression of mTOR(mammalian target of rapamycin)and its substrates in oral squamous cell carcinoma.Methods　mTOR and its substratesα1、α2、β1、β2isoforms of p70 S6 kinase(p70S6k) and 4EBP1 were examined by means of RT-PCR, Western-blot test.Results　The result of RT-PCR showed that in poorly differ- entiated tissue, the expression level ofmTOR and its substratesα1、α2、β1、β2isoforms of p70 S6k increased obviously, while that of 4EBP1 decreased, while that in well differentiated tissue was second to it, the normal oral tissue was the last. The expression of Western-blot was the same as the RT-PCR.Conclusion　The expression of mTOR and its substrates differs in different types of oral squamous cell carcinoma. The result suggests that mTOR, p70 S6K and 4EBP1 might play important roles in oral squamous cell carcinoma. It may be an important target protein to treat tumor in the future.

Objective　To investigate the relationship of Fas mRNA and protein expression and apoptosis in human oral squa- mous cell carcinoma.Methods　Northern blot and flow cytometry (TUNELmethod) were used to detectthe expression of FasmR- NA and Fas protein, cell cycle and apoptotic level in oral squamous cell carcinoma. The relationship between Fas gene expression and OSCC apoptosis was analyzed statistically.Results　Fas mRNA and protein could be detected in all five normal oral mucosa specimens. There was positive correlation between expression of Fas mRNA/protein and cell differentiation as well as apoptosis in OSCC(P<0.005).Conclusion　The expression of Fas genewas highly correlatedwiththe differentiation and apoptosis in OSCC.