[Abstract] Objective To investigate the influence of advanced glycation end products (AGEs) on autophagy of human periodontal ligament cells (hPDLCs) in vitro. Methods The hPDLCs were isolated from premolars extracted for orthodontic purpose and cultured in vitro using tissue culture method. hPDLCs was treated with different concentrations of AGEs (200μg/ml AGEs), and DMEM was used as negative control group (bovine serum albumin BSA). After0， 1，3，6 and 9 h of culture, these results were further substantiated by Western blot analysis、 electron microscopy and Immunofluorescence. Results We found that the lysosome activity significantly increased in AEGs group by electron microscopy and Immunofluorescence. Compared with 0h, the LC3-Ⅱ expression declined in AGEs group and negative control group at 1h. But after 1h, the LC3-Ⅱ expression was elevated and reached highest point at 3h in AGEs group, while remained unchanged in negative control group. Conclusion AGEs can strongly induce autophagy of the hPDLCs in vitro.

Objective　To study the influence of Osteopontin (OPN) on osteogenetic differentiation ability of dental pulp stem cells (DPSCs) induced by mineralizing culture medium, and to optimize its inducement conditions. Methods　DPSCs cultured in mineralizing culture medium worked as control group, and DPSCs cultured in mineralizing culture medium with OPN was the experimental group. The morphological changes of DPSCs were observed by the inverted phase contrast microscope; and the formation of mineralize nodules was detected with Alizarin red staining method; the expression levels of osteogenic related genes including bone sialoprotein (BSP), Runt-related transcription factor 2 (Runx-2), osteocalcin (OCN) and collagen-1 (Col-1) were detected by reverse transcription polymerase chain reaction (RT-RCR). Results　Alizarin red staining showed that mineralized nodules have formed after induced for 28 days in both groups, and the number and size of the mineralized nodules in experimental group was obviously larger than that in control group. The expressions of osteogenic related genes were all positive in both groups after 7 days. Expression levels of BSP, Runx - 2, Col-1and OCN genes of experimental group were significantly higher than control group. Conclusions　OPN can enhance the osteogenetic differentiation ability of dental pulp stem cells (DPSCs) induced by mineralizing culture medium.

Objective　 To study the expression of cytokeratin in cervical lymph nodes of patients with squamous cell carcinoma of the gingival .Methods: Immunohistochemical examination with pan-cytokeratin (CK-AE1/AE3) was performed on 28 positive lymph nodes and 139 negative lymph nodes that were from 17 patients with squamous cell carcinoma of gingival.Results:28 lymph nodes with metastasis shown by general pathological examination (HE stain) were positive for CK. 11 lymph nodes（in 9 patients） that were shown to have no metastasis by general examination were also positive for CK and 6 nodes were found in level Ⅰand 5 nodes were found in level Ⅱ.Conclusion: The immynohistochemical with pan-cytokeratin (CK-AE1/AE3) is a good method of detecting lymph node micrometastasis in squamous cell carcinoma of the gingival.

Objective　To investigate the expression and the clinical relevance of Livin in human oral squamous cell carcinoma. Methods　Retrospective study was used to test the expression of Livin in 46 cases of oral squamous cell carcinomas and then the correlation among the expression level, the clinical pathological parameters and the patient prognosis was analyzed and evaluated. Results In 46 cases, Livin expression of 29 cases were detected positive (63.0%). The expression of Livin was closely related with the metastasis（P=0.012）and the grade（P=0.005）, but was not obviously related with their prognoses（P=0.112）. Conclusion　Livin expression may be closely related with the tumorigenesis and development of human oral squamous cell carcinoma.

Objective　To study the expression and the significance of Cystatin B and Cystatin C in tongue squamous cell carcinoma as well as the function. Methods The data and the samples of 50 patients with tongue squamous cell carcinoma treated in Department of Oral and Maxillofacial Surgery, School of Stomatology, China Medical University from January 2010 to January 2011 were collected. Cystatin B and Cystatin C expression levels in tumor or adjacent normal tongue were examined with immunohistochemical method. Statistical analysis was performed. Results　Positive expression rates of Cystatin B in tongue squamous cell carcinoma cancer and adjacent normal tongue mucosa were 72.0% (36/50) and 36.0% (18/50), and the difference was statistically significant(P<0.05).The positive expression rate of cyatatin C were 68.0%(34/50) and 38.0%(19/50), and there was significant difference (P<0.05). Cyatatin B and Cystatin C were all correlated with pathological grades, and not correlated with patient's age, gender and the presence of lymph node metastasis. Conclusion　Cystatin B and Cystatin C may play some role in diagnosis of tongue squamous cell carcinoma and pathological grading.

Objective To explore the clinical effects of anterior maxilla micro-implant anchorage on the anterior teeth intrusion to improve gum-smile . Methods Fifteen patients with gum- smile and deep overbite with mean age of 9.7 ± 5.4 were selected , and micro- implant anchorages were inserted into the labial alveolar bone between the central incisors and the lateral incisor roots. Then 0.6 N force was used in each side, and duration of the intrusion anterior teeth on average was 6.2 ± 1.6） months. Relative parameters of soft and hard tissues before and after treatment were measured by cephalometric X-ray films. SPSSl3.0 software was used for statistical analysis. Results The vertical intrusion of the anterior teeth and the length of crown of incisors were reduced significantly (P <0.01), and both the overbite and overjet approached the normal range. Conclusions Micro- implant anchorage is effective in intruding anterior teeth, correcting the deep overbite and improving gum- smile.

Objective To study the antibacterial properties of Fe3＋-doped TiO2 film against Streptococcus mutans. Methods Pure TiO2 film and Fe3＋-doped TiO2 films were prepared by a sol-gel technique with dip coating method on Co-Cr alloy. With the cobalt-chromium alloy serving as the control group, the antibacterial properties of pure TiO2 film and Fe3＋-doped TiO2 films against Streptococcus mutans were evaluated with sticking-membrane method under ultraviolet (UV), fluorescent light and in the darkness. The doping content of Fe3＋ was measured as the antibacterial property was at its best. Results Under different lighting conditions, the antibacterial effects of pure TiO2 film group and Fe3+-doped TiO2 film were statistically different compared with the control group (P<0.05).The Fe3＋-doped TiO2 film appeared good antibacterial activity with the n(Fe3+) /n(Ti) of 2% under UV and dark conditions, while n(Fe3+) /n(Ti) of 1.5% under fluorescent light. Conclusion The Fe3＋-doped TiO2 film has more active antibacterial property than the pure TiO2 film, and it may also have certain antibacterial activity in the darkness. The antibacterial activity can be controlled by adjusting the relative ratio of n(Fe3+) /n(Ti).

Objective To study the effect of nano TiO2 on the masking ability of silicone rubber prosthesis after two different treatments to find the proper treatment suitable for the oral silicon rubber prosthesis masking agent and to offer theorial basis for clinical selection and colourity of prosthesis in maxillofacial region. Method Spectrophotometer was used to meter the color parameter L, a, b of TiO2 nano silicon rubber specimens treated in different ways respectively under black and white backgrounds (L=22.0，a=-1.0，b=-6.2)、white(L= 92.7，a=-0.9，b=-2.0). According to the formula ?E=[(?L )2 +(?a )2 +(?b )2 ]1/2 , the value of chromatism under black and white backgrounds was calculated, which showed the masking ability of the masking agent. Result There was no significant difference in the value of chromatism as the proportion fraction of nano TiO2 was small, but with the proportion fraction increasing, the value of chromatism of nano TiO2 with cladding silicone and aluminium was higher than that of the test pieces of the other treatment. Conclusion The dispersion property of nano TiO2 treated with silicone and aluminium is better than that treated with silane coupling agent. After two treatments, there is no obvious difference in the masking ability as the proportion fraction is small but with proportion fraction increasing, masking ability of nano TiO2 treated with silane coupling agent is much better.

Objective To evaluate the effects of artificial aging on bond durability of zirconia treated with different methods. Methods 128 zirconia/composite resin bonding specimens for 4groups were prepared. Surface conditioning and resin cement were used by groups: A=tribochemical silica coating + silane + Bis-GMA based resin cement; B=alumina sandblasting + self-adhesive resin cement; C=alumina sandblasting + zirconia primer Z-Prime Plus+ Bis-GMA based resin cement; D= alumina sandblasting + zirconia primer Z-Prime Plus+ self-adhesive resin cement. Each group was divided into 4 subgroups to receive different artificial aging as no aging, water storage for 40 days, thermal cycling for 1200 times, and thermal cycling for 12000 times after water storage for 40 days. The shear bond strength of each specimen was tested. The zirconia surface treated with tribochemical silica coating or alumina sandblasting was observed by a scanning electron microscopy and electron spectroscopy analysis was done. Results No statistically significant difference was found among the 4 groups whether accepting artificial aging or not. In each group, only the subgroup d showed significantly lower bond strength values and the difference was statistically significant. Conclusion Different artificial aging methods have different effects on bonding strength of zirconia.

Objective To detect the blood flow velocity changes of middle cerebral artery of the patients with edentulous jaws before and after BPS complete denture treatment, and to investigate the effect on the cerebral blood flow of BPS complete denture treatment. Methods The clinical patients with edentulous jaws were selected and treated with BPS complete denture. Before and after treatment, the artery systolic peak flow velocity (Vs), end-diastolic peak flow (Vd) and mean peak flow velocity (Vm) of middle cerebral artery were detected in calm and chewing state using TCD transracial doppler color ultrasound diagnostic apparatus. Results In calm state, Vm, Vs and Vd have significantly increased on 6 months post-treatment (P<0.05). In chewing state, Vs and Vm apparently increased on 3 months post-treatment, and Vd also increased on 6 months post-treatment (P<0.05). Conculsions BPS complete denture treatment could increase blood flow velocity of middle cerebral artery, and could make promoting effects on improving the cerebral blood flow and brain function of the patients with edentulous jaws.

Objective To measure and analyze the normal crown facial prominences among people of Han and Mongolian nationality in Hohhot, and to compare the differences of the crown facial prominences between Mongolians and Hans as well as the difference between genders. Methods 80 volunteers with normal occlusion were selected from five universities in Hohhot, among whom 40 were Hans and 40 were Mongolians with both sexes equally represented. The upper and lower jaws of the selected samples were scanned by the GE64 -slice spiral CT machine, and the scan images were measured .Then the differences between right and left sides, genders and ethnicities were observed and compared with paired-t test. Results ①The mean and standard deviation of crown facial prominence among men and women in Han and Mongolian nationality were established. ②The differences n U1、U4、U6、L4 and L5 among males between Mongolian and Han nationality were of statistical significance; the differences in U2、U6、L1 and L7 among females between Mongolian and Han nationality were statistically meaningful. Conclusion During orthodontic treatment, correctional quantity should be adjusted according to the differences in the Mongolians and the Hans and can’t be treated as the same.

Objective To evaluate the thickness of buccal cortical bone and bone depth at different heights in posterior area of mandible where mini-plants were placed．Methods Sixty-eight cone-beam CT（CBCT） images were selected randomly from the Affiliated Stomatology Hospital，China Medical University, which consisted of 36 male and 32 female ranging from 18 to 31 years old. Thickness of cortical bone between the first premolar distal and the second molar mesial at the height of 3，6，and 9 mm from the alveolar crest was determined. The data were analyzed statistically. Results There was no significant difference in the cortical bone thickness and bone depth between the left and right side（P ＞ 0.05）.And no significant difference was found between males and females（P ＞ 0.05）. The thickness of cortical bone and bone depth between the first molar and the second molar in mandible was maximum at 3 heights, between the first premolar and the second premolar in mandible the thickness and bone depth was the minimum at 3 heights. Conclusion The cortical bone thickness in the buccal posterior region and bone depth of mandible change along with the position changing sagittally and vertically，which should be considered in mini-plants implantation. A position as far from the alveolar crest as possible and near the distal end of the arch is the best in posterior area of mandible. Cortical bone thickness and bone depth of mandible are, on average, favorable for the insertion of orthodontic mini-implants.

Objective　To study the effect of different premolar extraction models on the incisor root resorption using panoramic radiography and cone beam computed tomography，and to provide document for the clinical treatment and diagnosis. .Methods　27 cases were divided into three groups:T0(non-extraction)、T1(extraction of the first premolar) and T2(extraction of the second premolar).Panoramic and CBCT images of all patients were taken immediately before and after treatment.The measurement of the root resorption was performed in the three groups.Results　Root resorption occurred in the three groups.CBCT showed that more significant root resorption occurred in T1 and T2 groups compared with T0 group.And the amount of resorption was more in T1 group than that in T2 group.Panoramic images showed that there was no significant difference in root resorption between T0 and T1 groups. Compared with T0 group,the resorption was more in T1 group.In T1 and T2 groups，no significant difference was found comparing panoramic and CBCT measurement while in T0 group,panoramic and CBCT measurement showed statistical difference.Conclusions　Different premolar extraction models had different effects on the incisor root resorption.The sensitivity of CBCT was better than panoramics.

[Abstract] Objective: To discuss the performance and coping strategies of dental disease imaging distortion. Methods: 14 dental disease cases of periapical radiographs or panoramic radiograph distortion were collected and the clinical data were analyzed retrospectively. Results: 11 cases of teeth were extracted, 2 cases completed root canal therapy and the osteoma was removed in 1 case. Conclusion: Dental diseases imaging distortion was quite complex, so we should organize consultation and discussion for those cases that can’t be confirmed to avoid blind extraction and try a variety of diagnostic methods and therapeutic regimen.

Objective　To compare the clinical effect of glass-fibre wire resin splint and steel wire resin splint on fixing loose traumatic anterior teeth teeth. Methods　46 cases of injured teeth from patients were randomly divided into two groups. Glass-fibre wire resin splints were used in the experimental group, and steel wire resin splints were used in the control group. Each group had 23 injured teeth. Mobility degrees of the traumatic teeth in the two groups were compared in two weeks after removal of the splint and three months later. The average operating time of each group was also compared. Results　The mobility degree of all the traumatic teeth in both groups decreased after fixation. There was no significant difference between two groups (P>0.05). The average operating time of the experimental group was significantly shorter than that of the control group. (P<0.01).Conclusion　In the short term, glass-fibre wire resin splint can obtain the same fixation effect as steel wire resin splint, but the former saves significant amount of operating time.

Objective To evaluate the arch width changes induced by Quick active and Damon passive self-ligating appliances on non-extraction correction of dental crowding. Methods 19 adolescent cases of mild-to-moderate skeletal class I dental crowding were reviewed in this randomized controlled trial. The patients were randomized into 2 groups: 10 subjects were treated with Quick active self-ligating system and the other 9 subjects were treated with Damon passive self-ligating system. The dental casts were analyzed before and after arch alignment and leveling. The changes of arch widths were analyzed with spss15.0 software. Results In Quick group, statistically significant increase in upper, lower premolar widths and widths between upper first molar was noted after treatment. Meanwhile in Damon group, statistically significant increase in upper premolar widths was noted after treatment. There was no significant difference in arch width changes before and after treatment between two groups. Conclusion The self-ligating system can effectively increase the arch widths. in order to achieve the purpose of non-extraction. There was no significant difference in efficiency of arch width increase between active and passive self-ligating systems.

Objective To evaluate the balance between pro-and anti-inflammatory cytokines in chronic periodontitis patients accompanied with bad repair body and its correlation with different clinical parameters of the periodontal status. Methods Forty two subjects were recruited to the study, including 22 patients with chronic periodontitis(CP) accompanied with bad repair body , 20 healthy controls (HC). Blood samples were collected to assess serum concentrations of IL-1β, IL-2, IL-6, TNF-α and IL-10 by means of enzyme-linked immune-sorbent assay(ELISA). Results Serum levels of pro-inflammatory cytokines (IL-1β and TNF-α) were significantly higher in CP patients than in HC groups (P<0.05), whereas the serum levels of anti-inflammatory cytokines (IL-10) was significantly lower in patients when compared to control (P<0.05). Serum IL-1β level was showed significant positive correlation with each of clinical periodontal parameters. Conversely, serum IL-10 levels had negative significant correlation with each of clinical periodontal parameters. Conclusion Cytokines may play an important role in pro-inflammatory response in serum of patients with chronic periodontitis accompanied with bad repair body. Moreover imbalance between pro- and anti-inflammatory cytokines could be involved in the initiation and progression of chronic periodontitis.

Ankylosed tooth is a kind of eruption abnormality of the teeth.It arises more often in primary molars,while it’s rarely that occlusal surface of tooth is lower than proximal gingival clinically.We report a rare case of ankylosed mandibular right second primary molar which is below the gingival has a deep caries in the occlusal surface,and we try to make a detailed introduction about epidemiology,clinical manifestations,diagnosis,and treatment of the disease.