Oral soft tissue has been a highlight topic these days. The morphology of gingival papilla is one of the most important factors influencing esthetics of oral soft tissue. The loss of gingival papilla height leads to black triangle. In anterior region, the black triangle not only results in functional disorder, but also brings in speech problems and esthetic concerns. Researchers from home and abroad reported some morphological factors influencing the height of gingival papilla: Age, gingival biotype, crown form, contact point-crest distance, interdental distance, divergence angle, embrasure morphology, etc. Clinicians must understand the factors that influence the presence of the interproximal papilla in order to prognosis the state of the papilla and to better fulfill the regeneration of lost gingival papilla.

Objective To study the effect of solid phase transformation on the metal-ceramic compatibility of Co- Cr alloy during firing programs. Methods 9 foils of Co-Cr and Ni-Cr alloy with the dimension of 25 mm×3 mm×0.5 mm were casted using lost wax technology respectively. Among them, 6 specimens were subjected to metal-ceramic bonding strength test（three point bending method）, the ceramic layer of 3 specimens were removed for X-ray diffraction（XRD） analysis. One cylindrical specimen of each alloy was casted for the test of coefficient of thermal expansion, cooling curves were recorded. Results The metal-ceramic bonding strength of Ni-Cr, Co-Cr alloy was （49.1±3.40）, （40.9± 2.02）MPa respectively. There was significant difference between the two groups’bonding strength（P=0.00）. The coefficient of thermal expansion in the 20-500 ℃ interval of Ni-Cr and Co-Cr alloy was 13.9×10-6, 13.8×10-6·K-1 respectively. XRD analysis indicated that the microstructure of Ni-Cr alloy was austenite. While Co-Cr alloy was constituted by fcc phase, hcp phase and σ phase. Conclusion During the cooling procedure, the transformation of fcc phase to hcp phase and segregation of needle-like σ phase intensify the linear contraction speed of Co-Cr alloy, which decreases
the metal-ceramic adaptability.

Objective To compare the susceptibility of Porphyromonas gingivalis to metronidazole at different planktonic cell densities and in biofilm, and to evaluate the role of cell density in antibiotic drug resistance in Porphyromonas gingivalis biofilm. Methods The minimum inhibitory concentration（MIC） and the minimum bactericidal concentration（ MBC） of metronidazole against Porphyromonas gingivalis were detected by a broth dilution method under a final inocula of 106 CFU·mL-1 and 109 CFU·mL-1（cell number equal to biofilm）. After the initial biofilm formed in the microtiter plate wells, the MIC and MBC of metronidazole to the intact and succedent resuspended biofilm were determined. Results The MIC and MBC of metronidazole against 106 CFU·mL-1 planktonic Porphyromonas gingivalis were 0.063, 0.125 mg·L-1 respectively. However, those against 109 CFU·mL-1 planktonic Porphyromonas gingivalis were 25, 50mg·L-1. Against intact Porphyromonas gingivalis biofilm, the MIC was 25mg·L-1 and MBC was higher than 125mg·L-1, those against resuspended biofilm was 25, 125 mg·L-1 respectively. Conclusion The resistance of Porphyromonas gingivalis to metronidazole increases along with the augment of the bacterial density. Cell density plays an important role in the resistance of biofilm. However, extracellular matrix and the integrity of biofilm may be the other influence factors for the biofilm resistance.

Objective The aim of this study was to determine the expression of genes of the oligodendrocyte lineagemyelin basic protein（Golli-MBP） in peripheral blood mononuclear cell（PBMC） in oral lichen planus（OLP） and to further understand the pathogenesis of OLP. Methods PBMC was obtained by density gradient centrifugation, and the expression of Golli-MBP in PBMC was investigated in erythematous/erosive OLP（20 cases）, reticular OLP（16 cases） and normal controls（19 cases） using reverse transcription-polymerase chain reaction（RT-PCR） and Western blot methods. Results RT-PCR results showed that Golli-MBP mRNA was overexpressed in erythematous/erosive and reticular OLP as compared with normal control group（P<0.01）. Western blot assay indicated that erythematous/erosive and reticular OLP patients had a higher expression level of Golli-MBP protein in PBMC than normal controls（P<0.01）. However, there were no significant differences between erythematous/erosive and reticular groups in Golli-MBP mRNA and protein expression（P>0.05）. Conclusion The data accumulated here strongly indicate that Golli-MBP was involved in the pathogenesis of OLP.

Objective The objective of this study is to investigate the effect of epidermal growth factor receptor （EGFR） monoclonal antibody MAb225 on repair of DNA double strand break（DNA-DSB） after radiation in tongue squamous cell carcinoma cell. Methods The single cell gel electrophoresis（SCGE） was performed to estimate the repair of DNA-DSB induced by radiation in human tongue carcinoma cells Tca8113 treated with or without MAb225. Expression of Ku70 and Ku80 were detected by semiquantitative reverse transcription polymerase chain reaction and Western bolt. Results Comet tail moment of MAb225 treated cell was significantly higher than untreated cell（P<0.05）. The expression of Ku70 and Ku80 were inhibited by MAb225. Conclusion MAb225 can inhibit repair of DNA-DSB induced by down-regulated expression of Ku70 and Ku80.

Objective To compare the fracture surface of the machinable infiltrated ceramic（MIC） prepared in different onditions, and to relate its strength and toughness to the differences in their microstructures. Methods The Al2O3 atrix were prepared, infiltrated by the machinable glass and crystallized. Based on sintering and infiltrating time and onditions, the specimens were divided into three groups: Perfect group, insufficiently infiltrated group, mal-sintered substrate roup. Specimens were fabricated, three point flexural strength and elastic modulus were tested, and the microstructure f the MIC fracture surfaces was analyzed by means of scanning electron micrograph（SEM） observation. Results he strength of the insufficiently infiltrated group and mal-sintered substrate group were lower than that of the perfect roup, and faults in the microstructure of these two groups also proved this. The foreland of glass infiltrating in the Al2O3 nd the interface of glass and complex demonstrated that the Al2O3 surface was smoother than the complex and there as a big crack in the glass but not in the complex which proved the crack resistibility of glass and Al2O3 were smaller han that of the complex（MIC）. Conclusion Correct preparing process could make the glass infiltrate into properly sintered l2O3 sufficiently which ensured best mechanical properties of the complex.

Objective To study the effect of basic fibroblast growth factor（bFGF） on the gene expression of syndecan- 4 by human periodontal ligament cell（PDLC） in culture, and discuss the effect of bFGF on human PDLC proliferation and migration. Methods 68 adolescent（12-18 years old） health premolar were collected, which were extracted for orthodontic reason. Human PDLC were cultured and stimulated by exogenous bFGF. After cultured 24, 48, 72 h, gene expression of syndecan-4 was detected by SYBR green quantitative real time polymerase chain reaction. Results The mRNA expression of syndecan-4 in 24 h group increased markedly than that in control group（P<0.01）, expecially in 1.0 ng·mL-1 group. 1.0 ng·mL-1 group in 48 h higher than that control group（P<0.05）. 1.0 ng·mL-1 group in 72 h compared with control group was lower（P<0.05）. Conclusion The mRNA expression of syndecan-4 was increased by bFGF at the beginning, but the expression was decreased with the time. The expression of such changes may be one of the important factors which participate in the migration process of PDLC.

Objective To investigate the effect of carbon ion implantation on the surface properties of denture base resins. Methods Twenty heat-curing denture base resins specimens were made in this study. All the specimens were equally divided into two groups randomly with each group ten specimens. One was experimental group for carbon ion implantation and the other was control group without any treatment. The nano-hardness, wettability and wearability of all the specimens were tested. Then one specimen chosen from each group was used for infrared spectrum analysis. Results There was statistical difference in nano-hardness, contact angle and quality loss between experimental group and control group（P<0.01）. New hydroxyl was formed in the surface of experimental group specimen from infrared spectrum analysis. Conclusion Carbon ion implantation has a positive effect in improving the surface properties of denture base resins.

Objective This retrospective study is to analyze the outcomes of cN0 stage tongue squamous cell carcinoma and to discuss a reasonable neck management for these cases. Methods Totally 132 cases of cN0 stage tongue squamous cell carcinomas were included. Seventy-one cases were performed neck dissection（group ND）, 61 cases were under wait-and-see（group WS）. The clinical, pathological and follow up data of two groups were analyzed. Results The cumulative three-year-survival between group ND and group WS were 87.3% and 83.4% respectively. In group ND, the survival of T1 and T2 cases were 89.3% and 83.3% respectively, while 89.6% and 58.3% in WS. For T2b cases which the size was larger than 3.0 cm, the survival of group WS was greatly lower than that of group ND. Both in ND and WS groups. The pathologically poor differentiation cases got poor survival than middle and well cases. Conclusion The wait-and-see policy is recommanded for T1 stage cN0 tongue squamous cell carcinoma. For T2 cases that the tumor size is smaller than 3.0 cm, the wait-and-see is also reasonable, while the neck dissection should be considered in cases of poor differentiation. For large T2 cases, the selective neck dissection should be performed.

Objective To compare the vibration parameters in reducible anterior disc displacement and symptomless youth, and explore the clinical diagnostic value of frequency spectrogram of temporomandibular joint（TMJ） sounds. Methods 21 youth with anterior disc displacement were included as experimental group, and 26 symptomless youth were included as control group. The joint vibrations during rhythmic maximal open-close jaw movement of all subjects were recorded. The sensitivity and specificity of total integral in diagnosis of reducible anterior disc displacement were calculated. Results All TMJ vibration parameters, include total integral, integral＜300 Hz, integral＞300 Hz, ＞300/＜300 Hz radio, peak amplitude, peak frequency and median frequency, were significantly higher in experimental group than that in control group（P＜0.05）. Along with the increasing of disc displacement degree, the TMJ vibration parameters were increasing, and total integral significantly increased（P＜0.05）. The total integral demonstrated a high sensitivity and specificity in diagnosis of anterior disc displacement with reduction（0.86 and 0.85, respectively）. Conclusion The TMJ vibration parameters are significantly higher in youth with reducible anterior disc displacement than that in symptomless youth. Different pathological stages of disc displacement show different TMJ sounds.

Objective To study clinicopathological features, diagnosis, differential diagnosis of oral Langerhans cell histiocytosis（LCH）, retrospective clinicopathologic study was carried on and a variety of immune phenotype were de -tected. Methods The clinicopathological features of 29 cases of oral LCH were analyzed. The immunohistochemical staining of S-100 protein, CD1a, CD83 and Ki-67 were used in above cases by immunohistochemical streptavidinbiotin peroxidase（SP） and Elivison two-step method. Statistical analysis was adopted for the results. Results Of the 29 cases of LCH, the expression of S-100 protein and CD1a were positive in 24 cases and negative in 5 cases, so 5 cases were excluded from the diagnosis of LCH. Among 24 cases of LCH, 15 patients were male and 9 were female. The median age was 7.50 years. 14 lesions were in the mandible, 5 were in the maxilla and 5 involved the mandible and maxilla. 9 cases were in stage Ⅰ, 13 in stage Ⅱ and 2 in stage Ⅲ, according to Bartnick classification. Immunohistochemistry showed all 24 cases staining for S-100 protein and CD1a were positive. Comparing with maxillofacial lesions involved soft tissue, Ki-67 positive rate was lower and CD83 positive rate was higher in maxillofacial single
bone lesion. Conclusion The immunohistochemical staining of S-100 protein and CD1a are important for the diagnosis
of LCH. Maxillofacial bone single LCH might have lower proliferative activity and a higher state of maturity. Maxillofacial
LCH involved soft tissue might have a higher proliferative activity and a lower state of maturity.

Objective To evaluate the method of adenovirus vector-mediated herpes simplex virus-thymidine kinase gene（ADV-TK）/ganciclovir（GCV） system and photodynamic therapy（PDT） for treating the oral malignant tumor. Methods Ten patients who were suffering from oral malignant tumor of the different positions were selected, and injected with the hematoporphyrin derivative（HPD）, irradiated by picking the corresponding laser frequency, and injected the ADV-TK gene into the tumor body and periphery. By the imaging and the hemodynamics analysis, the clinical efficacy after infusing vein with GCV was assessed. Results After the combination method treatments, patients’tumors appeared clear shrinkage or complete extinction. There was obvious fall of the blood flow volume in the tumor body. Imaging results showed significantly differences. So it was a perfect and effective treatment. Conclusion There are many advantages to apply the ADV-TK/GCV system and PDT treatment on the oral malignant tumor, minimal side effects and greater clinical security. It is a safe and credible therapy which can be offered for curing the oral malignant tumor systematically.

Objective To observe the occlusal contacts during protrusion and lateral movements in adolescent patients after orthodontic treatment. Methods Sixteen adolescent patients who achieved normal dentition after orthodontic treatment were selected as experimental group and 17 healthy adolescents and young adults with normal occlusion were selected as control group. The occlusal contacts during protrusion and lateral movements in the two groups were recorded with T-Scan Ⅱ system and compared. Results The prevalence of occlusal interferences in the posterior segment in the experimental group was high and most of them were on the second molars. The value of disclusion time during left lateral movements, right lateral movements and protrusion in the experimental group were （1.504±0.681）, （1.532±0.913）, （1.358±0.791）s. The value of disclusion time during left lateral movements, right lateral movements and protrusion in the control group were（0.470±0.059）,（0.483±0.045）,（0.482±0.047）s. The results in the experimental group were significantly longer than those of control group（P＜0.01）. Conclusion Although the patients achieved normal dentition after orthodontic treatment, their disclusion time were longer than those in healthy adolescents and young adults with normal occlusion.

Objective To study the periodontal health status of Hui and Han adults in Ningxia Hui autonomous region, thus to provide scientific basis for the establishment of oral health care policies in this region. Methods 2 628 adults in Ningxia Hui autonomous region were investigated in this study according to the criterion issued by World Health Organization on the basic methods of oral health investigation and China oral health third epidemiological survey protocol. The inspection item included gingival bleeding（bleeding on probing, BOP）, dental calculus, probing depth（PD） and attachment loss（AL）. SPSS 15.0 statistical software was applied to analyze the results. Results 1）The positive rate of BOP sites, detection rate of calculus and PD were peaked in 36-45 and 46-59 years old, but in the ≥60 age group rather lower. The prevalence of periodontitis and the percentage of AL≥4 mm sites were increased with the adults’age. 2）In addition to the percentage of AL≥4 mm sites, the differences of the other indicators between the genders were not statistically significant. 3）The positive rate of BOP sites, detection rate of calculus, PD, the prevalence of periodontitis and the percentage of AL≥4 mm sites were higher for the mountain areas than the plain areas. 4）Hui population’s positive rate of BOP sites, detection rate of calculus, PD, the prevalence of periodontitis and the percentage of AL≥ 4mm sites were significantly lower than the Han population in Ningxia. Conclusion The periodontal health status of adults in Ningxia Hui autonomous region is associated with age, gender, nationality and region.

Objective The aim of the present study is to investigate the prognosis and influencing factors of crownfractured young permanent teeth with pulp exposure. Methods Case records of crown-fractured young permanent teeth with pulp exposure in the Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology during 1991 to 2008 with more than 2 years follow-up were collected. These patients were treated with pulpotomy at the first visit at our hospital no matter whether these teeth were treated or untreated with direct pulp capping. The age of patients, interval between trauma and treatment, root development, mobility and tenderness to percussion were recorded. The prognosis was analyzed and Logistic regression was used to analyze the influencing factors. Results Totally 118 cases satisfied the inclusion criteria, including 136 crown-fractured teeth with pulp exposure. The patients of （8.8±1.2） years old were periodically monitored for （46.1±22.0） months. The success rate of pulpotomy after pulp exposure was 85.3%. Pulp necrosis occurred in 20 teeth （25.0±19.0） months after trauma. The extent of tenderness to percussion showed significant correlation with pulp necrosis, while the age of the patients, interval between injury and treatment, and mobility of the teeth were not related to pulp necrosis. Conclusion The success rate of pulpotomy after pulp exposure is good. Tenderness to percussion is an important signal of pulp necrosis. There are no evidence about the relationship between the patient’s age, interval between injury and treatment, mobility of the pulp-exposed teeth and the pulp prognosis.

Objective To investigate the changes in hemodynamics and depth of anesthesia under monitored anesthesia care（MAC） in patients undergoing percutaneous dilatational tracheostomy（PDT）. Methods Forty-six patients with oral cancer were divided into two groups with 23 cases each: Local anesthesia group（group L） and MAC group（group M）. Local and intratracheal surface anesthesia were performed with 2% lidocaine in group L. Midazolam, propofol and fentanyl were added to group M after local and intratracheal surface anesthesia, then PDT was carried out. During the induction, observer’s assessment of alertness/sedation（OAA/S） scale was used to assess the depth of sedation. Mean arterial blood pressure（MAP）, heart rate（HR）, state entropy（SE） and response entropy（RE）were recorded before anesthesia（basal value, T1）, after local anesthesia（T2）, after intravenous administration/before incision（T3）, during incision（T4）, during dilating with stretching pliers（T5） and endotracheal intubation（T6）. A postoperative follow-up was taken in group M. Results MAP and HR increased significantly at T4-T6 in group L and decreased at T3（P<0.05） with no change at T4-T6 in group M compared with those in T1. MAP and HR at T3-T6 in group M were obviously lower than those in group L . SE and RE at T3-T6 in group M were obviously lower than those at T1 or in group L（P<0.01） and decreased significantly with the reduction of OAA/S scale（P<0.05） during the induction. Intraoperative awareness in group M was not found through postoperative follow-up. Conclusion Patients undergoing PDT under MAC has more comfortability, more stable hemodynamics and no memory, so MAC is a better anesthesia for PDT than local anesthesia.

Objective To evaluate the effectiveness on the application of mechanical toothguide training box（TTB）  to chromatics teaching of prosthodontics. Methods 12 preclinical undergraduate students were chosen to participate in the VITA 3D-Master shade-matching system simulant toothguide training process using Linearguide Training Box program of TTB. Toothguide Trainer program considered as a test was performed on the trained undergraduate students group, the postgraduate students group as well as the clinical prosthodontists group with under 5-year clinical experience. The test scores, elapsed time and the coincidence of chromatics single factor matching were recorded each time, the shade-matching efficiency was calculated. The data was analyzed with SPSS 13.0 software. Results The shadematching efficiency of undergraduate students trained by TTB（64.03±18.82） was significantly higher than before（P＜0.05）, higher than the postgraduate students group and the clinical prosthodontists group（P＜0.05）. The coincidence of chromatics single factor matching of trained undergraduate students were 64.64%（lightness）, 88.57%（chroma）, 87.70% （hue）. Conclusion TTB is a effective tool for shade-mathing practice in chromatics teaching of prosthodontics. The trained undergraduate students are less sensitive in lightness-matching.

Objective To investigate effectiveness and safety of combined treatment with glucosamine hydrochloride orally and hyaluronate intraarticularly in patients with temporomandibular joint osteoarthritis. Methods Twenty eight participants who were diagnosed as temporomandibular joint osteoarthritis were randomly allocated to intervention and control groups（n=14）. The former received oral glucosamine hydrochloride（each day 1.44 g） and the latter placebo for four weeks. Both groups received intraarticular injection of hyaluronate for upper and inferior compartment, once a week for four weeks. Maximal mouth opening, pain on opening, deviation at the end of opening were measured at baseline and each week of follow up, quality of life was measured by using the instrument of oral health impact profile-14 （OHIP-14） at baseline and the fourth week. Intention-to-treat analysis was adopted for data analysis. Results All participants except two in control group adhered to the follow-up. Parameters on baseline were balanced between the two groups. Maximal mouth opening was significantly increased in intervention group compared with control group（P= 0.03） and decrease was found for pain on opening（P=0.02）. No statistical difference was detected between the two groups on deviation（P=0.67）. The intervention group didn’t show advantages compared with placebo on quality of life assessed by OHIP-14（P=0.77）. No serious adverse drug events were detected in both groups. Conclusion The glucosamine hydrochloride plus double joint cavity injection of hyaluronate is safe and may reduce pain scores and improve opening in patients with temporomandibular joint osteoarthritis.

Objective To detect the effects of human interleukin-1β（IL-1β） and Dexamethasone（DEX） on the expression level of keratinocyte growth factor（KGF） in cultured human fibroblasts of normal oral and oral lichen planus（OLP） mucosa. Methods Three concentration gradients of IL-1β and DEX were added to cultured fibroblasts of human normal oral and OLP mucosa respectively. 72 hours later, the supernatant was harvested for the detection of KGF concentration with enzyme linked immunosorbent assay（ELISA）. Total RNA of the fibroblasts was extracted and reverse transcribed. The resulting cDNA was then amplified by polymerase chain reaction（PCR） to detect the KGF mRNA. Results The results of the ELISA and PCR showed that the expression levels of KGF protein and mRNA were higher if the cells were treated with IL-1β. However, the expression levels of KGF protein and mRNA were significantly reduced if the fibroblasts were treated with DEX. Conclusion IL-1β can promote KGF expression levels of cultured normal oral and OLP fibroblasts, and it is concentration-dependent. While DEX can inhibit KGF expression of cultured normal oral and OLP fibroblasts, and it is also concentration-dependent.

Objective To study the effects of transection of inferior alveolar nerve（IAN） on the healing of mandibular fracture by investigating the changes of inflammatory factors expression, including tumor necrosis factor-α（TNF-α）, interleukin-1（IL-1） and interleukin-6（IL-6） in the denervated rabbits’bony callus. Methods 50 Chinese rabbits were randomly divided into the experimental group and control group, the experimental group underwent mandibular fracture and transection of IAN and the control group underwent mandibular fracture only. The bony callus were collected at 1, 2, 3, 5 and 7 d after operation, respectively. The expression of TNF-α, IL-1 and IL-6 in callus was detected by enzyme linked immunosorbent assay（ELISA）, and the mRNA of TNF-α was detected by reverse transcription-polymerase chain reaction（RT-PCR）. Results In the experimental group, at the 1st day after operation, the expression of TNF-α（75.1%）, IL-1（68.3%） and IL-6（72.7%） was lower than that in control group（P<0.05）. At the 2nd day, the expression of IL-1（75.5%） was still lower than that in control group, but the expression of TNF-α was higher than that in control group. In the next observation points, all inflammatory factors decreased, and there was no difference between experimental and control groups. In RT-PCR, the detection of TNF-α mRNA in the experimental group was lower than that in control group. Conclusion In the haematoma of mandibular fracture healing, transection of IAN causes neurohumor decrease, depression and delay of inflammatory reaction. It is unfavorable to fracture healing.

Objective To research the relationship between the virulence factors of Saccharomyces albicans（S.albicans） and the random amplified polymorphic DNA（RAPD） bands of them, and establish the regression model by multiple regression analysis. Methods Extracellular phospholipase, secreted proteinase, ability to generate germ tubes and adhere to oral mucosal cells of 92 strains of S.albicans were measured in vitro; RAPD-polymerase chain reaction（RAPDPCR） was used to get their bands. Multiple regression for virulence factors of S.albicans and RAPD-PCR bands was established. Results The extracellular phospholipase activity was associated with 4 RAPD bands: 350, 450, 650 and 1 300 bp（P<0.05）; secreted proteinase activity of S.albicans was associated with 2 bands: 350 and 1 200 bp（P<0.05）; the ability of germ tube produce was associated with 2 bands: 400 and 550 bp（P<0.05）. Conclusion Some RAPD bands will reflect the virulence factors of S.albicans indirectly. These bands would contain some important messages for regulation of S.albicans virulence factors.

Objective To assess the effects of 1-step method of changing the buccal position of the transported bone after distraction on early bone formation. Methods The custom-made bidirectional distraction devices were used. Total of 8 adult mongrel dogs were procured. The bilaterally mandible premolars were extracted. After 1 month, the complete osteotomy was performed and the devices were placed. The gradual distraction was started after 1 week latency at the rate of 1mm per day, total 6 mm in height was achieved. The 1-step method of changing the buccal position of the transported bone was performed the day after the vertical distraction period in one side of the animals, and the other side as the controlled side. All animals were killed after a 7 days consolidation. The vascular system was stained post mortem carbon ink perfusion to assess possible damages. Quantitative evaluations of bone density were performed with dual-energy X-ray absorptiometry（DEXA）, analysis of the ratio of vascular square was conducted in a computer. Results All animals tolerated the procedures well. After vertical distraction, the tested side can be moved 3 mm in buccal direction. DEXA examination showed that the density of the distracted bone was no statistical difference in both the tested and the controlled side. Vascular damage was not observed, and there was no statistical difference in the ratio of vascular square by analyzing the histological section in computer. Conclusion In some extent, 1-step method of changing the buccal position of the transported bone after distraction can mold the regenerate bone to correct the axial displacement, without endangering early callus formation and vascularization.

Objective To establish animal models for research of orthodontic tooth under rapid movement through distraction osteogenesis of the periodontal ligament, and to approach the rules of bone formation and the relationship between new bone formation and angiogenesis. Methods 48 rats of which the right maxillary first molars were removed were randomly divided into experimental and orthodontic control group. The orthodontic model was established according to traditional method, and the stretch device was installed in the experimental group after reducing the second molar’s mesial bone resistance. Four animals in each group were randomly selected to be killed at 6 time points（at day 0, 3, 5, 10, 20, and 30）. After specimens were obtained, immunohistochemical staining was done. The expression of vascular endothelial growth factor（VEGF） and osteocalcin（OC） were investigated. Results In the experimental group, VEGF was mainly expressed in vascular endothelial cells, fibroblasts, osteoblasts, osteoclasts, and bone cells. The positive expression of VEGF gradually increased, the peak appeared at day 10 on the tension side, and the other side was at day 5. OC-positive signals were seen in the extracellular matrix of periodontal ligament and osteoblastic cells, and its peak appeared at day 10 on both tension and pressure side. The expression of VEGF and OC were similar in orthodontic control group, but the level was lower. Conclusion VEGF and OC involve in the remodeling of periodontal tissues and play an important role during periodontal ligament distraction osteogenesis. Angiogenesis is earlier than bone formation, or both appear simultaneously.

Objective To study the effect of hyperthermia on anti-invasion of Tca8113 and the expression change of matrix metalloproteinase-13（MMP-13） and calcium-binding protein S100A4（S100A4）. Methods Tca8113 cell pools were incubated at 43℃ for 0, 40, 80, 120 min, respectively, and at 37, 41, 43, 45 ℃ respectively for 80 min. The effect of high temperatures on the invasion ability of Tca8113 was measured in vitro. The slides of cells were made and incubated at 43 ℃ for 0, 40, 80, 120 min, respectively. Immunocytochemical method was employed for detecting the expression change of MMP-13 and S100A4 protein. Tca8113 cells were incubated at 43 ℃ for 0, 40, 80, 120 min respectively and at 37, 41, 43, 45 ℃ respectively for 80 min. Western blot method was conducted for detecting the expressionchange of MMP-13 and S100A4 protein. Results As incubating time at higher temperature lasted, the proportion of the cells with invasion ability decreased. Except groups of 40 min and 80 min at 43 ℃ and 41, 43 ℃ for 80 min, the rest groups show significant statistic differences（P<0.05）. The expression intensity of MMP-13 and S100A4 proteins in Tca8113 cells would decrease as incubating time at higher temperature lasted. The content of MMP-13 and S100A4 proteins would decrease as incubating time at higher temperature lasted or incubating  emperature increased.Except the groups of 40, 80 min at 43 ℃ and 41, 43 ℃ for 80 min, statistic differences were identified（P<0.05）. Conclusion The invasion of Tca8113 could be inhibited by hyperthermia. The mechanism of this effect may be due to protein expression inhibition of MMP-13 and S100A4.

Papillon-Lefèvre syndrome（PLS） is a very rare syndrome of autosomal recessive inheritance characterized by palmoplantar hyperkeratosis and a severe destructive periodontitis, leading to premature loss of both primary and permanent dentitions. This article reported a boy who was diagnosed as having PLS.

The broken root dislocated into the maxillary sinus is a common complication during the teeth extraction. This article reported broken roots of four patients dislocated into maxillary sinus were removed successfully by endoscope under local anesthesia through windowing in inferior nasal meatus. It is an efficient method, which has less wounds and shorter surgical time.

Granulicatella species are facultative anaerobic, catalase-negative Gram-positive cocci, oral microbiome researches find out Granulicatella species are dominant bacteria in oral cavity which may cause opportunistic infection like periodontal disease, endodontic infection. This review summarized research progress of Granulicatella species.