[Abstract] Objective To study the expression of GRP78 and BCL-2 in ameloblasts of fluorosis rats and to explore the injury diversity of fluoride to ameloblasts at different stages. Methods 20 wistar rats were selected and fed with fluoride water. 8 weeks later, they were sacrificed and immunohistochemistry and HE staining were used to detect the changes of ameloblast and the expression of GRP78,BCL-2 in rat incisors. Metamorphic microscope images analysis system and spss13.0 software were used to analyze the data. Result The expression of GRP78 in ameloblast secretory and secretory phase was higher than that in transformation period and mature period. BCL-2 had the highest expression in secretory phase and transition period,however, it declined in secretory stage and mature stage. The differences between groups were statistically significant.(P<0.05） Conclusions The injury of fluoride to ameloblasts at different times is different.

Objective To study the effects of iodine on osteoblasts in pup rats. Methods Female Wistar rats (n = 20) after pregnancy were randomly divided into four groups: control group Ⅰ, control group Ⅱ, iodine deficient group, iodine overdose group. The control group Ⅰ was fed a normal diet and drank deionized water, while the control group Ⅱ was fed an iodine-deficient diet and drank deionized water with adequate iodine during the experiment. The iodine deficient group was fed an iodine-deficient diet and drank deionized water during the experiment, while the iodine overdose group was fed a normal diet and drank deionized water with high iodine. On gestational day 18, the levels of thyroid hormones and thyroid stimulating hormone were tested in pregnant rats. On postnatal day 0, alkaline phosphatase activities and proliferation of osteoblasts were observed in pup rats. Results The levels of thyroid hormones in iodine deficient group were significant lower than controls(all P<0.05), while the levels of thyroid stimulating hormone increased significantly(all P<0.05). There were no significant differences of the levels of thyroid hormones between the iodine overdose group and controls (all P>0.05). However, a significant upregulation of thyroid stimulating hormone was observed in the iodine overdose group relative to the controls (all P<0.05). The alkaline phosphatase activities and proliferation of osteoblasts were significantly down-regulated in iodine deficient group compared to the other groups (all P<0.05). Conclusion Iodine deficiency in pregnant rats led to downregulation of alkaline phosphatase activities and proliferation of osteoblasts in pup rats.

objective To observe the effect of Clostridium perfringens enterotoxin on expression of tight junction proteins in rat submandibular glands Methods recombinant plasmid pET16bHis10C-CPE was constructed, CPE COOH-terminal fragments (C-CPE) were purified. Rat submandibular glands (SMGs) were isolated and then perfused with C-CPE for 3h. After perfusion, the morphology of epithelia cells and expression of ZO-1 and Claudin-4 in SMGs were observed by H.E and immunofluorescence staining. Results After perfusion with C-CPE, no epithelial cells damage was observed and the expression of ZO-1 and Claudin-4 was no change. Conclusions Purified C-CPE fragments have no cytotoxic effect on epithelial cells in SMGs.

Abstract: Objective To analyze the course of the mandibular canal, providing the theoretical basis for implanting and bone grafting. Methods Mandibular data of 90 people from Jiangsu province obtained by cone-beam computed tomography were collected and analyzed by NNT 4.6 considering the effects of genders and sides. Results The mean distance from the border of mandibular canal to the alveolar crest was increased first then started to decrease. That to the buccal bone wall was gradually increased from mesial to distal. No significant differences were detected in genders and sides. (p>0.05) That to the lingual bone wall and inferior margin and was gradually decreased from mesial to distal. Significant differences were detected at where 2mm distal to mental foramem both in genders and sides which were inferior in female and left side. (p<0.05) That to the apexes of posterior teeth was gradually decreased from mesial to distal. No significant differences were detected. (p>0.05) Conclusion Mandibular canal position to the alveolar crest and buccal bone wall was symmetrical between two sides and similar in both genders. But that to the lingual bone wall and inferior margin is variable between genders and sides in the area close to mental foramen (within 2mm) in Jiangsu province people.

Objective To study the effect of different surface pretreatments to high-strength glass fibers on the mechanical properties of glass fiber reinforced resin composite posts. Methods Glass fibers were divided into 4 groups for different surface treatments: no surface pretreatment; 450℃ calcination; etching with 10% HCl for 1 h after 450 ℃ calcination; etching with 10% HCl for 3 h after 450 ℃ calcination. All groups of glass fibers were immersed in KH570 solution before they were mixed into resin matrix, and then they were light -cured within a special mold to prepare the FRC posts. The flexure modulus, flexure strength and fracture load of FRC specimens were measured by universal mechanical testing machine. Statistical analysis was carried out with one-way analysis of variance (ANOVA) and the SNK tests(α=0.05). After three-point flexural bending test, the cross-section surface of FRC and the fracture surface of FRC were observed by a field emission scanning electron microscope (SEM). Results Different surface pretreatments of glass fibers affect the mechanical properties of FRC posts. FRC posts composed of glass fibers that were treated by 450 ℃ calcination and silanization presented the best overall performance, with flexure modulus (37.70±1.46) GPa; flexure strength (737.00±25.51) MPa; flexure load (196.53±6.80) N, which showed significant difference compared with other groups(P＜0.05)．Conclusion Glass fibers treated by 450 ℃ calcination and silanization could significantly improve the properties of FRC specimens.

Abstract: Objective To evaluate the antimicrobial effect and the clinical curative effects of active silver ion antibacterial solution in treatment of periapical periodontitis in permanent teeth. Methods 80 patients of apical periodontitis were randomly divided into 2 groups with 40 for each group.The samples were instrumented with Mtwo,and then irrigated respectively as following:（group A） syringe irrigation with hydrogen peroxide and physiological saline alternately after root canal preparation （group B）syringe irrigation with hydrogen peroxide and active silver ion antibacterial solution alternately. Bacterial culture was taken before and after the treatment, while the curative effect evaluation was carried out 6 months later. Results A significant decrease in the number of CFUs was observed after treatment in all the groups. Additionally, group B had a significantly higher antimicrobial efficacy as measured by the number of CFUs than group A (P <0.05). In the review half a year later，there was no significant difference between the two groups in efficiency ( P >0.05). Conclusions Active silver ion antibacterial solution is a better choice for clinical root canal irrigation.Combining it with 3% hydrogen peroxide solution is much more effective in eliminating bacterial in the infected root canal, which can improve the clinical result. Its long-term efficacy still needs further research．

Objective　To investigate expression and clinical significance of NOD1 in tougue squamous cell carcinoma (TSCC). Methods　Immunohistochemical staining and RT-qPCR were applied to evaluate NOD1 expression in TSCC and non-cancer tougue epithelial tissues. Its clinical significance would also be analyzed. T-test was performed to assess the statistical significance of mRNA expression between the two groups using SPSS 13.0. Among many groups (>2 groups), statistical significance was determined by two-way analysis of variance. Results　NOD1 was expressed in the cytoplasm. NOD1 expression was significantly lower in TSCC tissues (60 .0％, 15/25）than that in non-cancer tougue epithelial tissues（80 .0％，20/25 (P <0.05). NOD1 messenger RNA expression in TSCC tissues was 0.437±0.103 times of that in non-cancer tougue epithelial tissues(p<0.05). Conclusion　The RNA and protein expression of NOD1 are significantly lower in TSCC. However, further studies with functional evaluation of the NOD1 are warranted to replicate and extend the significance of the findings.

Abstract: Objective To explore the prevalence and distribution pattern of the root variations of permanent maxillary first and second molars in a Chinese Han population in Suzhou Prefecture. Methods Cone-beam computed tomography images of dentitions were collected retrospectively from 257 Han Chinese patients in Suzhou Stomatological Hospital. The incidences of the root variations were observed and determined. The trait frequency differences between genders and sides were tested with Chi-square tests. Correlations in the occurrence of the root variations between antimeric teeth were analyzed with the Spearman rank correlation test. Results The occurrence rate of fused roots in maxillary first molars was 3.1% (15/484 teeth). The frequency of maxillary second molars with 3 separated roots was 69.7% (285/409 teeth), and the bilateral concurrence rate was 66.1% (37/56). The differences between genders and sides were not statistically significant (P > 0.05). The most common variation form was the fusion of the mesiobuccal and distobuccal roots (11.7%), followed by the single rooted form (10.5%) and the fusion of the mesiobuccal and palatal roots (4.9).The correlation coefficient for the antimeric second molars was 0.607 (P < 0.01). Conclusion The root variation rarely occur in maxillary first molars whereas in maxillary second molars, the prevalence of fused roots is high in the Chinese Han population in Suzhou prefecture. It is of great clinical significance to understand and grasp their distribution patterns.

Objective Retrospective evaluate the effect of the treatment of the Objective To evaluate the effect of the treatment of the Class Ⅱ division 1 malocclusion by the light wire and straight wire technique. Methods 30 adolescents of the Class Ⅱ division 1 malocclusion were selected.They were treated with light wire technique (15) and straight wire technique(15)respectively. Model measurement and cephalometric radiographs were taken and analyzed before and after treatment. Statistical method was used to determine if there were significant differences between the 2 techniques. Results There was no significant difference in the sagittal and vertical relationship. They all gained a good occlusion after treatment. The L1-MP decreased less in the light wire technique group than in the straight wire technique group.Average treatment time in the light wire technique group was shorter than the other group. Conclusions Light wire technique is a clinically effective method for correcting the Class Ⅱ division 1 malocclusion, while it might be weak in the lower incisors control after the treatment.

Objective To evaluate the treatment effects of J hook headgear and micro-screws on intrusion of upper incisor. Methods 21 adult patients with overgrown maxillary alveolar were chosen and divided into two groups: J hook headgear group (n=9), and micro-screws group (n=12), using J hook headgear and micro-screws to lower upper incisor respectively. Cephalometric analysis was performed before and after treatment, and cephalometric indicators changes and treatment time of two groups were compared. Results U1-PP of the two groups were significantly reduced (P <0.01), and the reduction of micro-screws group was greater than the J hook headgear group (P <0.01); as for U1-Sv, micro-screws group increased (P <0.01), while J hook headgear group decreased (P <0.01); in terms of U1/PP corner micro-screws group increased (P <0.01), and J hook headgear group did not change significantly (P> 0.05); U6-PP both groups have no statistically significant change (P> 0.05); as for U6-Sv, micro-screws group increased (P <0.01), while there was no statistical significant change in J hook headgear group (P> 0.05); the treatment time of micro-screws group was less than that of J hook headgear group (P <0.01). Conclusion Both J hook headgear and micro-screws have effect on the intrusion of incisors, and micro-screws is more effective than J hook headgear with less time, but it will cause anterior teeth labial inclination and increase anchorage burden.

Objective To analyze retraction and intrusion effects of high positioned mini screws which were put between upper second premolars and first molars. Methods Ten Orthodontic patients with anterior teeth protrusion and gummy smile were included. Twenty mini screws were put and 150-200 g force were added to retract anterior teeth one week later. Effects of retraction and intrusion were analyzed. Results Profiles of all cases improved effectively and gummy smiles were corrected. Conclusion High positioned mini screws can effectively retract and intrude anterior teeth.

Objective To observe the clinical effects of Forsus appliance in the treatment of Mandibular Retrusion during the peak stage of development. Methods 11 Mandibular Retrusion patients were treated with Forsus appliance. Winceph 7.0 Cephalograms Analysis Software was used to analyze lateral cephalograms before and after the treatment. .Results ANB decreased by 3.36°while SNB increased by 3.05° and the mandibular body length was 3.34mm longer. The distance from Pg to OLP plane increased by 2.32mm with overjet decreased and the molar relationship improved significantly. Conclusion Forsus appliance is effective to correct Mandibular retrusion at the peak stage of development. It can stimulate the mandibular growth and improve sagittal discrepancy and soft tissue profile convexity significantly.

Objective To evaluate the colour stability, surface roughness and ?exural strength of heat-curing denture base resin after using five denture cleansers. Methods Samples were prepared from heat-curing denture base resin and immersed in Polident, Victoria-C，Protefix，0.2% chlorhexidine gluconate ，Y-Kelin denture cleansers and distilled water. The color changes (ΔE), the roughness and the ?exural strength were then measured. Results The color changes were significantly greater in the 0.2% chlorhexidine gluconate ,Y-Kelin denture cleansers than in the control group. The ΔE values quanti?ed by the NBS (National Bureau of Standards) were classi?ed as Slight in all groups. When comparing the surface roughness and ?exural strength, no statistically significant difference was found among the different immersion procedures. Conclusion Immersion in 0.2% chlorhexidine gluconate and Y-Kelin denture cleansers influenced the color stability of heat-curing denture base resin after a 180-day use, but it was clinically acceptable. Polident, Victoria-C, Protefix did not influence the properties.

Objective To investigate the effects of different energies of Er: YAG laser pretreatment on the shear bond strength of self-adhesive resin cement .Methods Seventy extracted human molars collected in accordance with the inclusion criteria were randomly divided into 7 groups according to the different Er:YAG laser energy pretreatments on the dentin surface :Group A (control), GroupB(50 mJ,10 Hz),GroupC(100 mJ,10 Hz),GroupD(150 mJ,10 Hz),GroupE(200 mJ,10 Hz),GroupF(250 mJ,10 Hz),GroupG(300 mJ,10 Hz).Two teeth were selected randomly from each group and 3mm thick dentin slices cut from the teeth were observed under scanning electron microscopy after being pretreated according to the respective requirements .The remaining eight teeth were prepared into the consistent standards dentin surface after being embedded ,and then bonded with the self-adhesive resin cement RelyXTM Unicem and Everest ZS zirconia ceramic after pretreatment according to the respective requirements. 24h later, the shear bond strength was tested and a statistical analysis was performed. Result Scanning electron microscopy showed that the dentin surface morphology pretreated by Er：YAG laser changed into tough irregular one significantly, and the dentinal tubules became open without the smear layer. Peritubular dentin and intertubular dentin suggested demineralization and presented a better bonding surface in a appropriate energy range. The results showed that the Er：YAG laser pretreatment could enhance the bong strength of RelyXTM Unicem self-adhesive resin （P<0.01);there was significant difference between Group C、D、E and Group A（P<0.05).Conclusions The study shows that bond strength is closely related to the dentin bonding surface, and suitable energy of Er：YAG laser pretreatment can obtain better dentin bonding surface, improve the shear bond strength of the self-adhesive resin and dentin and zirconia ceramic.

Purpose : To Compare the clinical effect with two methods of repairing the flared root canals, semi-precious metal cast post core restoration and fiber post combined with accessory post resin core restoration. Methods: Choosing 68 flared root canal cases in clinic in the period from May 2012 to May 2013, 32 of them are repaired by semi-precious metal cast post core, and the rest are repaired by fiber post combined with accessory post resin core, compare the clinical effect in the next and second year. Results: The clinical survival of semi-precious metal cast post core is 87.5%,and the clinical survival of fiber post combined with accessory post resin core is 100%. The clinical effect of two methods has different (P<0.05). Conclusion: The clinical effect of repairing flared root canals by fiber post combined with accessory post resin core is better than by semi-precious metal cast post core.

Objective To evaluate the prevalence and distribution of fused teeth in primary dentition of preschoolers in Kunming. Methods: 3116 children aged from 3 to 6 years old were randomly enrolled in a cross-sectional study. Fused teeth were assessed through visual examinations. Results Among the 3116 subjects, a total of 85 individuals (2.73%) presented with fusion of primary teeth without sex predilection. The fused teeth were typically located in the lower anterior region(89.41％),and mainly occurred unilaterally(83.53％). Of the 99 fused teeth, 7 (17.17)％was accompanied with caries, without predilection between left and right side. Conclusion A certain number of children suffer from fused teeth, which may cause series of complications, and pediatric dentists should pay more attention to fused teeth.

To summarize the clinical and pathological characteristics of heterotopic acinic cell carcinoma of oromaxillo-facial region. A case of acinic cell carcinoma of gingiva was reported and the relevant literatures were reviewed and analyzed. The heterotopic acinic cell carcinoma grows slowly. Clinical symptom is pain or numbness. Surgery is the main means of treatment. Radiotherapy or chemotherapy is added after operation if necessary. The recurrence rate is low and malignant transformation is rare.