Salivary gland tumors are a group of the most common tumors in the oral and maxillofacial region with obvious characteristics of clinical, histopathologic, and therapeutic aspects. During the past 50 years, our research group performed a systemic study on salivary gland tumors including imaging diagnosis, fine needle aspiration cytology, FT-mid-IR fiber optics spectroscopy, histopathologic features and biological behaviour of the tumors, functional parotid surgery, and ¹²⁵I seed implant branchytherapy. More reasonable principles of management for various types of the tumors were put forward based on the histopathologic features of the tumors. The surgical techniques were modified and the postoperative complications were reduced obviously. Thus, the quality of life of the patients was improved greatly.

Our work focused on the studies on the expression and function of transient receptor potential vanilloid subtype 1 (TRPV1) in the submandibular gland. By using reverse transcription-polymerase chain reaction (RT-PCR), Western blotting, and immunofluorescence, our data demonstrated the expression and distribution characteristics of TRPV1 in rabbit and human submandibular glands, as well as rat submandibular gland cell line SMG-C6. Furthermore, the possible intracellular signal molecules involved in the TRPV1-modulated saliva secretion were explored. Activation of TRPV1 increased the intracellular Ca²⁺ concentration, upregulated the expression of aquaporin 5 (AQP5), the main transporter that mediate water secretion through transcellular pathway, and led to AQP5 redistribution. Extracellular signal-regulated kinase 1/2 (ERK1/2) was involved in the TRPV1-regulated AQP5 content. Besides, TRPV1 activation also modulated the expression, distribution, and function of tight junction protein, and increased paracellular permeability. ERK1/2 and myosin light chain 2 (MLC2) were responsible for the regulation of TRPV1on tight junction properties. Taken together, our work suggested that TRPV1 was a potential target to promote saliva secretion, and activation of TRPV1 might provide a new and safe therapeutic strategy to ameliorate submandibular gland hypofunction.

Objective：To evaluate the differences of clinical parameters and putative periodontal pathogens in sites of different probing depth (PD) reduction after non-surgical periodontal treatment in patients with aggressive periodontitis (AgP). Methods: Clinical examinations including plaque index, probing depth (PD), attachment level (AL) and bleeding index (BI), and full-mouth periapical photographs were collected from 20 patients with AgP. All the patients received non-surgical periodontal treatment, including oral hygiene instruction, supra-gingival scaling, subgingival scaling and root planing (SRP) and were followed up for 6 months post-therapy. Gingival crevicular fluids (GCF) were collected at 1 site in each quadrant before and at the end of 6 months post-therapy. Six kinds of putative periodontal pathogens and 6 kinds of short chain fatty acids (SCFAs) were detected in the GCF samples. Results: The baseline clinical parameters of PD, AL and BI, the baseline concentration of succinic acid, acetic acid, propionic acid and butyric acid, and the prevalence of Treponema denticola were significantly higher in sites with PD reduction more than 2 mm sites compared with PD reduction no more than 2 mm sites ［(7.7±1.2) mm vs. (5.1±1.8) mm, (6.3±1.9) mm vs. (4.5±2.2) mm, 3.8±0.4 vs. 3.3±0.8, 1.66 mmol/L vs. 1.10 mmol/L, 31.67 mmol/L vs.17.78 mmol/L, 3.31 mmol/L vs.1.95 mmol/L, 84.6% vs. 56.1%, P<0.05］. However, there were no significant differences in the clinical parameters, the 6 kinds of putative periodontal pathogen detection and SCFAs concentration between the 2 groups at the end of 6 months post-treatment. In sites with PD>5 mm at the end of 6 months post-therapy, all were found with red complex bacteria infection. Conclusion: The baseline clinical parameters are important factors in predicting PD reduction after non-surgical periodontal treatment in patients with AgP. In sites with deep pockets after non-surgical periodontal treatment, the active control of red complex bacteria is recommended.

Objective: To compare the bone dimensional changes following tooth extraction alone with extraction plus ridge preservation (using deproteinized boving bone mineral Bio-Oss^® and bioresorbable collagen mambrane Bio-Gide^®) in periodontal compromised extraction sockets.  Methods: Eighteen molars of sixteen subjects requiring tooth extraction because of periodontal destruction were enrolled in this study. The subjects were assigned to the control group (extraction alone, EXT) or to the test group (ridge-preservation procedure with Bio-Oss^® and Bio-Gide^®, RP). Parallel periapical X-rays and cone-beam computed tomography (CBCT) scans were taken immediately after tooth extraction alone or plus ridge-preservation (baseline) and 6 months later. The changes of horizontal ridge width and vertical ridge height were assessed. Results: At the central buccal aspect, the ridge height increased 2.9 mm in RP group, and reduced 1.0 mm in EXT group. At the distal buccal aspect, the ridge height increased 1.45 mm in RP group, and reduced 1.45 mm in EXT group. The differences between the groups reached statistical significance (P<0.05). The mean ridge width increased at the 1 mm below the crest (the horizontal ridge width was measured with grafting material at three levels at 1 mm below the most coronal aspect of the crest, HW1), which amounted to 3.40 to 5.80 mm in RP group, and 1.45 to 2.90 mm in EXT group. The mean ridge increased at the 4 mm below the crest (the horizontal ridge width was measured with grafting material at three levels at 4 mm below the most coronal aspect of the crest，HW4), which amounted to 0.40 to 3.50 mm in RP group, and reduced 0.10 to increased 0.15 mm in EXT group. The test group and the control group were not significantly different (P>0.05).Conclusion: The ridgepreservation approach using Bio-Oss^® in combination with Bio-Gide^® can significantly increase vertical ridge height and horizontal ridge width after tooth extraction compared with extraction alone in periodontal compromised molars.

Objective： To evaluate the feasibility of full-mouth debridement (subgingival scaling and root planning, SRP) by 2 times within 1 week and compare the clinical effects of different sequences of debridement-antibiotic usage in patients with severe chronic periodontitis (CP). Methods: A doubleblinded, placebo-controlled, randomized clinical trial was conducted in 30 severe CP patients (14 males and 16 females, 40.5±8.4 years old on average from 35 to 60) receiving 3 different sequences of debridement-antibiotictherapy: Group A, antibiotic usage (metronidazole, MTZ, 0.2 g, tid, 7 d; amoxicillin, AMX 0.5 g, tid, 7 d) was started together with SRP (completed by 2 times in 7 d); Group B, antibiotic usage (MTZ 0.2 g, tid, 7 d; AMX 0.5 g, tid, 7 d) was started 1 d after SRP(completed by 2 times in 7 d); Group C, SRP alone［probing depth (PD), bleeding index (BI) and tooth mobility］ was examined. The average full-mouth probing depth, the average fullmouth proximal probing depth (pPD), the percentage of sites with PD＞5 mm (PD＞5 mm%), the percentage of sites with proximal PD＞5 mm (pPD＞5 mm%), the average bleeding index (BI) and the percentage of sites with bleeding on probing (BOP%) were calculated. Clinical examinations were performed at baseline and 2 months post therapy. Results: (1) Compared with baseline conditions, all the subjects showed clinical improvements in all the parameters evaluated 2 months post therapy, P＜0.05. (2) Significant difference were observed in the average PD changes between Group A ［(2.15±0.42) mm］, Group B ［(1.76±0.29) mm］ and Group C ［(1.57±0.33) mm］, P＜0.05. No significant difference was observed in the average PD changes between Group B and Group C, P=0.354. Significant differences were observed in the average pPD changes between Group A ［(2.45±0.43)mm］ and Group C［(1.90±0.48) mm］, P＜0.05. No significant difference was observed in BI and BOP% changes between Group A，Group B and Group C. Conclusion: For patients with severe chronic periodontitis, it is safe and feasible to receive full-mouth SRP by 2 times within 1 week. The shortterm (2 months) advantages in PD changes are observed in patients receiving SRP and antibiotic usage at the same time comparing with patients using antibiotics after SRP or SRP alone.

Objective: To isolate P-cadherin positive and negative oral gingival epithelial cells, and to compare the biological characteristics with junctional epithelial cells.  Methods: Human oral gingival epithelial cells and junctional epithelial cells were cultured. P-cadherin positive and negative cells were isolated from oral gingival epithelial cells. The cellular adhesion, proliferation and migration were measured and compared. Results: The P-cadherin positive cells accounted for 20% of oral gingival epithelial cells. Compared with juctional epithelial cells, P-cadherin positive oral gingival epithelial cells showed similar properties of adhesion and migration, and stronger proliferation ability (0.72±0.06 vs. 0.60±0.05, P<0.05). P-cadherin negative oral gingival epithelial cells showed weaker ability of adhesion (48%±6% vs. 87%±11%, P<0.05), proliferation (0.36±0.04 vs. 0.60±0.05, P<0.05) and migration (10.3±2.7 vs. 23.4±4.8, P<0.05). Conclusion: P-cadherin positive oral gingival epithelial cells showed some similar but different biological characteristics, compared with juctional epithelial cells, which suggested that during the process of transforming oral gingival epithelial cells into juctional epithelial cells, complex gene and protein changes were involved instead of simply cellular migration.

Objective: To investigate the changes of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa B ligand (RANKL) level in perio-implant crevicular fluid (PICF) and to monitor the development of the stability of Straumann^® tissue-level implants by resonance frequency analysis (RFA) during the early phases of healing. Methods: A total of 35 implants (length 10 mm) were placed. PICF samples were collected with filter paper strips at baseline, 1, 2, 3, 4, 6, 8, and 12 weeks post-surgery, respectively. The OPG, RANKL levels were determined by ELISA method. At the same time points, the implant stability quotient (ISQ) values were determined with OsstellTM mentor. Results: During healing, PICF-OPG levels increased significantly 2 weeks after surgery when compared with the 4th-, 6th-, 8th- and 12th-week reevaluation (P<0.05). The OPG/RANKL ratio in PICF was significantly higher (P<0.05) than that in gingival crevicular fluid at 1 week post-surgery. ISQ slightly fluctuated within the first 4 weeks after installation. Following this, the ISQ values increased steadily for all the implants and up to 12 weeks. Significant differences were noted between the mean ISQ values at the 12 th-week and other observation time points. Conclusion: The PICF-OPG levels may be effective in monitoring the process of osseointegration. All the ISQ values indicated the stability of Straumann^®  implants over a 12-week healing period. RFA is a reliable and effective assistant to monitor implant stability.

Objective: To investigate the expression patterns of E-cadherin and P-cadherin in murinetooth germs at early developmental stages. Methods: Mandible samples of CD1 mice from embryonic day 12.5 to postnatal day 3.5 were collected. The expressions of E-cadherin and P-cadherin in murine mandibular first molar germs were detected by immunofluorescence and observed under confocal fluorescence microscope. HE staining was performed for tissue morphology. Results: Both E-cadherin and P-cadherin were widely expressed in the epithelial tissues through early developmental stages. The E-cadherin expression was increased in polarizing pre-ameloblasts, whereas the P-cadherin expression declined. The expression of the P-cadherin could be detected in epithelial tissues before bud stage, and expressed in mature ameloblasts at secretory stage. Conclusion: The E-cadherin and P-cadherin expressed in different spatiotemporal expression patterns, indicating their individual functions during tooth development. P-cadherin might function in the secretion and mineralization of enamel.

Objective: To construct and evaluate a novel tissue-engineered bone composed of murine stromal cell-derived factor 1(mSDF-1), simvastatin (SIM) and collagen scaffold （Bio-Oss^®）, serving as a cell-homing approach for bone formation. Methods:  In the study, 32 ICR mice were randomly divided into 4 groups，each group including 8 mice. The drug-loaded collagen scaffolds were implanted subcutaneously onto the cranium of each mouse according to the groups: (1) 1 ∶50 (volume ratio) dimethyl sulfoxide (DMSO) / phosphate-buffered saline(PBS) solution + collagen scaffold (blank control group); (2) 10^-3 mol/L SIM solution + collagen scaffold (SIM group); (3) 200 mg/L mSDF-1solution + collagen scaffold (mSDF-1 group); and (4) 10^-3 mol/L SIM +200 mg/L mSDF-1 solution + collagen scaffold (SIM + mSDF-1 group). One week after implantation, the mice were treated by injecting the same drug solution mentioned above around the scaffold once a day for two days. The specimens were harvested 6 weeks after implantation and the bone formation was evaluated by soft X-ray analysis, HE staining and immunohistochemical staining. Angiogenesis of each group was checked by calculation of vessels in each tissue section. Results: Six weeks after implantation, the collagen scaffolds were retrieved. The value of gray scale for the SIM+mSDF-1 group［（421 836.5±65 425.7）pixels］ was significantly higher than that of the blank control group［（153 345.6±45 222.2）pixels, P<0.01］, the SIM group ［（158 119.2±100 284.2）pixels, P<0.01］, and the mSDF-1 group［（255 529.5±152 142.4）pixels, P<0.05］; HE staining analysis revealed that significant bone formation was achieved in the SIM + mSDF-1 group; The immunohistochemical staining showed the existence of osteopontin and osteocalcin in the SIM + mSDF-1 group; There were more vessels in the SIM+mSDF-1 group［（46±8）vessels/mm²］ than in the blank control group ［(23±7) vessels/mm², P<0.01］, and the SIM group［(24±6) vessels/mm², P<0.01］. Conclusion: The novel tissue-engineered bone composed of mSDF-1, SIM and collagen scaffolds has the potential to form bone subcutaneously in vivo. It represents a novel method of in vivo bone regeneration without seed cell delivery.

Objective: To evaluate the synergistic antibacterial effects of lysozyme with ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) on Enterococcus faecalis (E. faecalis) and Porphyromonas endodontalis (P. endodontalis). Methods: E. faecalis and P. endodontalis were cultured and adjusted to 10⁸ CFU/mL. Then 0.3, 0.5, 1, 2, 5, 10, 50, 100, 150 and 300 g/L of lysozyme were prepared with deionized water; and the lysozyme solutions were mixed with 0.5, 1.0, 2.0 g/L of EDTA-2Na, respectively. The bacteria and lysosome with/without EDTA-2Na interacted for 15 min, then water-soluble tetrazolium (WST) working solution was added and the activity of the bacteria was calculated by measuring optical densities at 450 nm and 630 nm with microplate spectrophotometer. Results: Regarding the pure lysozyme from 0.5 g/L to 150 g/L, more E. faecalis and P. endodontalis were inhibited when the concentration of lysozyme was higher, especially for E. faecalis. There was synergistic effect of lysozyme with EDTA-2Na on antibacterial activity, which was related to the concentration of lysozyme. On E. faecalis, the antibacterial activity of lysozyme with EDTA-2Na was 1.2-3.7 folds than the pure lysozyme when the concentration of lysozyme was 0.5-50 g/L (P<0.05), and on P. endodontalis, the antibacterial activity of lysozyme with EDTA-2Na was 1.3-3.5 folds than the pure lysozyme when the concentration of lysozyme was 0.5-10 g/L (P<0.05). When the concentration of lysozyme was higher than 100 g/L, EDTA-2Na did not show synergistic effect on the antibacterial activity (P>0.05). Conclusion: For E. faecalis and P. endodontalis, a low concentration of lysozyme with EDTA-2Na showed significant synergistic antibacterial activity, while a high concentration of lysozyme with EDTA-2Na did not.

Objective: To investigate the possibility of predicting facial nerve involvement in the patients with parotid tumors using facial electroneurography (ENoG). Methods: In the study, 53 patients with primary parotid tumors were included in the study, 28 were benign tumors and 25 were malignant. There was no significant difference of tumor locations and sizes between the two groups. House-Brackmann facial nerve function evaluation was gradeⅠin all the patients who received examination of facial electroneurography, including stimulation strength, amplitude, and latent time bilaterally. The facial electroneurography results in the affected side were compared with the results of contralateral normal side, intraoperative appearance and postoperative histopathological diagnosis. The facial electroneurography results were analyzed by Wilcoxon signed rank test and receiver operator characteristic (ROC) curve. Results: During the facial electroneurography examination, the mean stimulation strength in the patients with benign parotid tumor was 20.0 mA. There was significant decrease in the amplitude at the affected side compared with the normal side upon posterior auricular stimulation (P<0.05). But there was no significant difference in the latent time between the bilateral sides (P>0.05). However, in the patients with malignant parotid tumor, the mean stimulation strength was higher at 24.5 mA. There was significant decrease in the amplitude or even no response at the affected side compared to the normal side upon posterior auricular stimulation (P<0.05). No response was detected in the multiple branches of facial nerve of affected sides in 36.0% patients upon posterior auricular stimulation. The amplitude of branches Ⅲ and Ⅳ was significantly lower at the affected side than that at the normal side upon anterior auricular stimulation (P<0.05). The area under the ROC curve for ENoG was 0.884. Conclusion: When the facial nerve was involved by the parotid tumors, the stimulation strength in the electroneurography was larger. There was significant difference in the amplitude and the latent time of the facial nerve between the affected side and the normal side upon the posterior auricular stimulation. The rate of absence of reaction wave was higher in the patients with malignant tumors. It was feasible to predict the facial nerve involvement by ENoG for the parotid gland tumor patients without clinical appearances of facial paralysis.

Objective: To explore the reinforcement of polyglycidyl methacrylate (PGMA) pre-impregnated quartz fiber mesh in denture base materials by investigation of interface compatibility and fracture resistance. Methods: 1-layer, 2-layer, 3-layer PGMA pre-impregnated quartz fiber meshes, electrolyzed cobalt-chromium alloy mesh and cobalt-chromium alloy mesh conditioned by metal primer were integrated in polymethyl methacrylate (PMMA) resin by sandwich embedding method. Block samples of 5 groups were prepared (40 mm×15 mm×2 mm). Fracture resistance was determined in a 3-point bending test at 2 mm/min. Scanning electron microscope (SEM), micrographs were taken from the fractured surfaces to analyze the bonding interface compatibility. Results: The group of 3-layer PGMA pre-impregnated quartz fiber mesh presented the highest elastic modulus of 6 406 MPa and flexural strength of 227 MPa among the five groups, while the 1-layer and 2-layer expressed the similar elastic modulus and flexural strength to the pure PMMA group. The metal groups demonstrated better mechanical properties, while the metal surface conditioner played much better. The metal surface conditioner pre-impregnated cobalt-chromium alloy and PGMA pre-impregnated quartz fiber mesh showed compatible interface with PMMA. Conclusion: The mechanical properties were improved by the increasing of the fiber by adding the more meshed. Although the benign interface did help the compatibility, the quantity of the fibers played an important role in the strength.

Objective: To compare the peri-implant tissue stability between immediate implant and delayed implant in maxillary anterior region after loading 2 years.  Methods: In the study, 38 patients with single anterior tooth loss in the Second Clinical Division of Peking University School and Hospital of Stomatology from October 2010 to December 2011 were enrolled, and 43 implants were inserted. The gingival contour was induced using implant-supported temporary crowns prior to restoration till permanent prostheses delivered. The gingival papilla height, labial gingival margin level and peri-implant bone level were measured immediately after the permanent restoration and 2 years later. Results: In the study, 16 patients were treated by immediate implant for 17 implants; 22 patients were treated by delayed implant for 26 implants. The implant stability quotient (ISQ) value of the 2 groups showed no significant difference before permanent restoration (P>0.05). In all the cases after loading 2 years, the average mesial gingival papilla height in the implant area of the immediate group and delayed group increased by (0.15±0.42) mm and (0.06±0.65) mm, respectively; the distal gingival papilla height increased by (0.06±0.50) mm and (0.02±0.57) mm respectively; while the labial gingival margin level shrinkages were (0.15±0.23) mm and (0.15±0.46) mm, respectively. The periimplant bone losses in the mesial side were (0.67±0.35) mm and (0.69±0.49) mm, respectively, while in the distal side were (0.73±0.31) mm and (0.75±0.48) mm, respectively. All these indicators showed no significant difference between the 2 groups (P>0.05). Conclusion: Both the cases obtained optimizer results after loading 2 years, and the soft and hard tissues around the implant were very stable, which means that both the protocols can achieve reliable therapeutic effects. If we can handle the indications, immediate implant for anterior teeth shows similar efficacy with delayed implant in the short term. But immediate implant in terms of shortening the course of treatment is clearly superior to delayed implant.

Objective: To compare influences of different retention attachments on stress among supporting structures. Methods: By 3-dimensional laser scanner and reverse engineering computer aided design (CAD) software, a basic partially edentulous digital model with mandibular premolar and molar missing was established. Implant attachment and removable partial dentures (RPD) were added into the basic model to build three kinds of models: RPD only, RPD + implant + Locator attachment, and RPD + implant + Magfit attachment. Vertical and inclined loads were put on artificial teeth unilaterally. By means of 3dimensional finite element analysis, the stress distribution and displacement of the main supportive structures were compared. Results: A complete 3dimensional finite element model was established, which contained tooth structure, and periodontal structures. The displacement of the denture was smaller in Locator (9.38 μm vertically, 45.48 μm obliquely) and Magfit models (9.54 μm vertically, 39.45 μm obliquely) compared with nonimplant RPD model (95.27 μm vertically, 155.70 μm obliquely). Compared with the two different attachments, cortical bone stress value was higher in Locator model (Locator model 10.850 MPa vertically, 43.760 MPa obliquely; Magfit model 7.100 MPa vertically, 19.260 MPa obliquely).The stress value of abutment periodontal ligamentin Magfit model (0.420 MPa vertically) was lower than that in Locator model (0.520 MPa vertically). Conclusion: The existence of implant could reduce maximum von Mises value of each supportive structure when Kennedy Ⅰpartially edentulous mandible was restored. Comparing the structure of Magfit and Locator attachment, the contact of Magfit attachment was rigid, while Locator was resilient. Locator attachment could improve stability of the denture dramatically. Locator had stronger effect on defending horizontal movement of the denture.

Objective: To analyze the biomechanics trait of one-piece computer aided design and computer aided manufacture (CAD/CAM) zirconia post and core by the three-dimensional finite element.  Methods: The three-dimensional finite element models of three upper central incisors restored with one-piece CAD/CAM zirconia post and core (group 1), refabricated zirconia post and hot-pressed porcelain core (group 2), and cast gold alloy post and core (group 3) were built by geometry method respectively. 100 N vertical loading through the central incisor models long axis and 100 N loading along directing at an angle of 45° with the models long axis were used to imitate the central incisor stress state in biting and mandible physiological protraction movement. Results: Under vertical loading, the restored teeth without dentin ferrule, the maximum VonMises stress value of the tooth root in group 1 was the least（11.02 N）, which was the largest （13.17 N）in group 2. The stress became weaker from the upper to the lower of the tooth root. The maximum Von-Mises stress value of the tooth root, post and core became smaller while the restored teeth with the 2.0 mm high dentin ferrule. Under directing at an angle of 45° loading, without the design of dentin ferrule in the restored teeth, the maximum Von-Mises stress value of the post and core in group 1 was the greatest（20.45 N）, while that stress of post and core in group 3 was the smallest（13.61 N）. With 2.0 mm high dentin ferrule design in the restored teeth, the tooth root stress became weaker. The maximum Von-Mises stress value of the tooth root was the greatest (14.10 N) in group 3, but which was the lowest (13.38 N) in group 1. Conclusion: The results of the three-dimensional finite element analysis infers that one-piece zirconia post and core restoration is more beneficial to disperse the bite force than the prefabricated zirconia post and the cast gold alloy post and core. The onepiece of zirconia post and core is good to protect the teeth and keep the restoration intact.

Objective: To evaluate the precision of digital impressions taken under simulated clinical impression taking conditions with TRIOS and to compare with the precision of extraoral digitalizations. Methods: Six #14-#17 epoxy resin dentitions with extracted #16 tooth preparations embedded were made. For each artificial dentition, (1)a silicone rubber impression was taken with individual tray, poured with type IV plaster，and digitalized with 3Shape D700 model scanner for 10 times; (2) fastened to a dental simulator, 10 digital impressions for each were taken with 3Shape TRIOS intraoral scanner. To assess the precision, best-fit algorithm and 3D comparison were conducted between repeated scan models pairwise by Geomagic Qualify 12.0, exported as averaged errors (AE) and color-coded diagrams. Non-parametric analysis was performed to compare the precisions of digital impressions and model images. The color-coded diagrams were used to show the deviations distributions. Results: The mean of AE for digital impressions was 7.058 281 μm, which was greater than that of 4.092 363 μm for the model images (P<0.05). However, the means and medians of AE for digital impressions were no more than 10 μm, which meant that the consistency between the digital impressions was good. The deviations distribution was uniform in the model images,while nonuniform in the digital impressions with greater deviations lay mainly around the shoulders and interproximal surfaces. Conclusion: Digital impressions with TRIOS are of good precision and up to the clinical standard. Shoulders and interproximal surfaces scanning are more difficult.

Objective: To assess the correlations between objective measurements of 108 finished orthodontic cases and subjective assessments made by 69 orthodontic specialists, to explore the statistically significant measuring categories of cast and cephalogram and to validate the regression model. Methods:  A stratified random sample of 108 cases was drawn from the large sample of 2 383 patients who finished orthodontic treatment between July 2006 and August 2008 in six orthodontic treatment centers around China. For each patient, the post-treatment information sources evaluated in this study included standardized plaster study casts and a lateral cephalometric X-ray image. These information sources were evaluated both singly and in combination by a panel of 69 orthodontic specialists. The average subjective grading scores of 69 orthodontists were regarded as the gold standard. Six examiners used the peer assessment rating (PAR) index and American board of orthodontics-objective grading system(ABO-OGS) to measure all the study casts respectively and three other examiners measured all the lateral cephalometric X-ray images by using customized software. The objective measuring data were correlated with the gold standard. The correlations between the objective measurement and the subjective evaluation were assessed, the statistically significant measuring categories of cast and cephalogram were explored and the regression model was validated. Results: The ABO-OGS scores of “occlusal relationship” correlated most strongly with the subjective scores of cast (r=0.655, P<0.01), and the secondarily correlated category with those were the PAR scores of “overjet” (r=0.525, P<0.01). The proclination of the lower incisors correlated most strongly with the subjective scores of cephalogram (r=0.446, P<0.01), and the secondarily correlated category with those was the protrusion of the lower lips (r=0.436, P<0.01). Nine components were predictive for the post-treatment model and lateral cephalometric film(Post-M+C) outcome: alignment (ABO-OGS), occlusal relationship (ABO-OGS), interproximal contact(ABO-OGS), L1/NB(°), overjet (PAR), SNB(°), occlusal contacts (ABO-OGS), U1/SN2(°) and centerline (PAR). These 9 components accounted for 72% of the variability in the average subjective grading scores. Conclusion: The objective regression model could replace the averaged opinion of Chinese orthodontic experts effectively, making objective assessment of orthodontic treatment outcome for Chinese patients.

Objective: To evaluate facial soft tissue 3-deminsion changes of skeletal Class Ⅲ malocclusion patients after orthognathic surgery using structure light scanning technique. Methods: Eight patients ［3 males and 5 females, aged (27.08±4.42) years］ with Class Ⅲ dentoskeletal relationship who underwent a bimaxillary orthognathic surgical procedure involving advancement of the maxilla by Le Fort Ⅰ osteotomy and mandibular setback by bilateral sagittal split ramus osteotomy (BSSO) and genioplasty to correct deformity were included. 3D facial images were obtained by structure light scanner for all the patients 2 weeks preoperatively and 6 months postoperatively. The facial soft tissue changes were evaluated in 3-dimension. The linear distances and angulation changes for facial soft tissue landmarks were analyzed. The soft tissue volumetric changes were assessed too. Results: There were significant differences in the sagittal and vertical changes of soft tissue landmarks. The greatest amount of soft tissue change was close to lips. There were more volumetric changes in the chin than in the maxilla, and fewer in the forehead. Conclusion: After biomaxillary surgery, there were significant facial soft tissue differences mainly in the sagittal and vertical dimension for skeletal Class Ⅲ patients. The structure light 3D scanning technique can be accurately used to estimate the soft tissue changes in patients who undergo orthognathic surgery.

Objective: To identify nasal width changes occurring after Le FortⅠosteotomy and to compare prospectively the effect of three surgical techniques for controlling postoperative nasal width.  Methods: In the study, 79 patients (22 male and 57 female, mean age 23.2±3.4 years), who received Le Fort Ⅰ osteotomy at Peking University Hospital of Stomatology from 2011 to 2014, were randomly divided into three groups. Group 1 was treated with traditional intraoral alar base cinch suture (ABCS); Group 2 with extraoral ABCS, and Group 3 with traditional ABCS plus an extra intraoral suture at points G.lat. All the patients had taken 3D photos using 3dMD camera before operation, and 3, and 6 months after operation. The nasal widths, which were indicated as distances between Sbal-Sbal, G.lat-G.lat and Al-Al, were measured by two examiners in the 3D photos three times with a time-interval of one week. SPSS 13.0 was used to do the statistic analysis. Results: At the end of the postoperative 6 months, the nasal widths lessened as compared with the postoperative 3 months. No significant differences were found between the three groups 6 months after the operation. The degree of the postoperative nasal width widening had positive correlation with that of the intraoperative nasal width widening, and had negative correlation with the initial nasal width and the amount of post-suture narrowing. Conclusion: There is no difference between three suturing techniques for controlling nasal width widening after Le Fort Ⅰ osteotomy. The postoperative nasal width-widening can’t be totally avoided, and the alteration might last at least 6 months after the operation. For patients with narrow nasal width and need to move maxilla forward, more overcorrection of ABCS is needed to control the postoperative nasal base widening.

Objective: To evaluate the prophylactic application of antibiotics in oral and maxillofacial surgery and to provide a scientific basis for its reasonable use. Methods:  The use of prophylactic antibiotics in the oral and maxillofacial surgery was conducted in our hospital from January 2011 to August 2013 based on a retrospective survey, and the conditions and affecting factors were analyzed. Results: The utilization rates of prophylactic antibiotics were respectively 98.9%, 61.8%, and 24.6%, showing a downward trend. But the infection rate of surgical site did not significantly increase, and by Fisher’s exact test, the difference was not significant (P>0.05). Surgical site infections (SSI) rates did not rise between using and not using prophylactic antibiotics (P>0.05). Conclusion: The use of prophylactic antibiotics is greatly influenced by the policy, and along with the decline in antibiotic usage, SSI have not increased significantly.

Objective: To establish a method of morphologic measurement of the mandibles and obtain the average values of three dimensional morphologic measurements of the mandibles. Methods: A method of morphologic measurement of the mandibles was established firstly. The three dimensional CT data of 54 normal adult skulls were measured by this method. The data were analyzed by SPSS 13.0 statistical software. Results: In the study, 84 groups of mean values and standard deviations of the length, width, height, depth, thickness and angle of the mandibular contour in males and females were obtained. There were significant differences between the male and the female in the 66 of the 84 groups data, while the 16 of the 84 groups data had no significant differences and distributed symmetry on both sides of the mandibles. No correlation was found in the mandibular contour data in length, width, height and depth. Conclusion: The characteristics of adult mandibular contours are different between males and females, indicating that each individual has its own morphologic features.

Objective: To evaluate effects of color matching of different cavosurface margins on the resin composites in vitro.Methods: Twenty extracted human premolars with an A2 shade buccal surface were used in this study. Rectangular shaped cavities (3.0 mm depth, 2.0 mm width, 2.0 mm length) were prepared in the center of the buccal surfaces. The gingival and occlusal cavosurface margins were prepared to be either shoulder or bevel; the other cavosurface margins remained vertical. Ten teeth were filled with Clearfil AP-X (AP), the other ten with Clearfil Majesty (MJ) and light cured. The color difference at the cavosurface margin area was measured using a spectrophotometer (CrystalEye) and evaluated by 3 observers subjectively. The data were statistically analyzed using repeated measures ANOVA and Chi-square test. Results: When measured by CrystalEye, the color difference between the tooth and resin composite was reduced from the center of restoration to the cavosurface margin area. Both objective and subjective evaluations showed that for AP, the color difference at the cavosurface margin area had no statistical difference among 3 types of the margins; for MJ, the color difference at bevel margin area was significantly smaller than that at the vertical margin area. Conclusion: The resin composite restorations produced the color matching at marginal area. The color matching of resin composites with higher diffused light transmission property is more susceptible to the type of cavosurface margins. Preparing bevels may reduce the color difference between the restoration and tooth surface.

Objective: To investigate the bonding strength of different resin composites.  Methods: Methacrylate-based resin APX and silorane-based resin composite P90 were chosen in this study, with their corresponding adhesives Clearfil SE Bond (SE) and Filtek P90 System Adhesive (SA). The specimens were divided into three groups: (1) bulk group, filling each block with the same composite, then curing; (2) direct filling group, curing and polishing one composite, then filling a new composite directly; (3) bonding group, after curing and polishing one composite, conditioning the surface with adhesives, then filling a new composite. Cut each resin blocks into 1 mm×1 mm×14 mm each piece, detecting the microtensile strength, and analyzing by One-Way ANOVA and LSD. Results: (1) The microtensile strength of the bulk group was the highest. (2) In direct filling group, the microtensile strength of 4 subgroups showed no statistical significance with each other but lower than that of the bulk group. (3) In bonding group, the microtensile strength of repairing with APX was higher than that with P90. When repairing with same composite, the microtensile strength was higher if the resin type of substrates was same with restorations than that was different. The microtensile strength of adhesives SE was higher than that of SA. (4) The sorting of the microtensile strength: bulk>SE bonding APX>SA bonding APX>SE bonding P90=direct filling>SA bonding P90. Conclusion: Retention force is higher when substrates are repaired with methacrylate-based resins and corresponding adhesives. Retention force is lower when repaired with silorane-based composites and corresponding adhesives. Types of the substrate composites show no influence on the bonding strength.

Objective: To compare the incidences of root cracks after canal instrumentation with HyFlex CM system and the ProTaper Universal system.  Methods: Sixty mandibular incisors were mounted in resin blocks with simulated periodontal ligaments, and the apex was exposed. The control group of 20 teeth was not prepared, and the other 40 teeth were divided into 2 experimental groups (n=20). The 40 root canals of the experimental groups were instrumented using HyFlex CM and ProTaper Universal to the major apical foramen (AF). The horizontal sections 1 mm, 2 mm, and 3 mm from the apex were observed under an optical stereomicroscope at 25×magnification. The presence of cracks was noted. Results: No cracks were found in the control teeth. Cracks were found in 1 of 20 (5%) teeth in HyFlex CM group, and 17 of 20 (85%) teeth in ProTaper Universal group. The difference between the two experimental groups was statistically significant (P<0.01). Conclusion: The HyFlex CM files caused fewer root cracks than the ProTaper Universal files during the root canal instrumentation.

Objective: To compare the level of dental anxiety and dental behavior between dental fear children with dental treatment under general anaesthesia (GA) and those under restraint.  Methods: The GA group included 31 dental fear children aged 4-6-year-old who received dental treatment under the GA. The restraint group included 31 dental fear children aged 4-6-year-old who received dental treatment under the restraint. Age, gender, parent’s education level, decayed-missing-filled tooth (dmft) and face version of the Modified Child Dental Anxiety Scale (MCDASf) score before treatment were matched between the two groups. The Chinese version of MCDASf was used to evaluate the level of dental anxiety in each child before treatment, right after treatment and before examination at recall visit 2-3 weeks after treatment. And the Chinese version of Venham Clinical Anxiety and Cooperative Behavior Scale was used to evaluate children’s dental behavior in each child before treatment and before examination at recall visit 2-3 weeks after treatment. Results: The average scores of MCDASf in GA group right after treatment and before recall were lower than that before treatment. The difference was statistically significant (P<0.05). Furthermore, the average score of MCDASf  before recall was lower than those after treatment, and the difference was statistically significant (P<0.05). The average scores of MCDASf in restraint group right after treatment and 2-3 weeks after treatment were higher than those before treatment, but the difference was not statistically significant (P>0.05). Children’s dental behavior was significantly improved at recall visit in both groups (P<0.01). Conclusion: Dental fear could be reduced by treatment under GA. The children’s dental behavior was improved after GA. Restraint did not result in the significant elevation of dental anxiety level, but dental behavior was improved after restraint during the shortterm recall.

Objective: To analyze the pulpal prognosis of replanted permanent teeth in children and to examine the associated factors. Methods: The samples consisted of 67 children with 81 avulsed permanent teeth treated in Peking University Hospital of Stomatology from 2000 to 2012. Their clinical data of the replanted teeth were collected, and the follow-up period was no less than 12 months. The pulpal prognosis was classified as pulp necrosis and pulp non-necrosis. Results: The replantation within 30 minutes after avulsion led to the most significant increase in pulpal healing (P＜0.05). The dental pulp of 80% (4/5) young permanent teeth replanted within 30 minutes remained vital, while all the teeth replanted after 30 minutes developed pulp necrosis within 60 days after replantation. Conclusion: The extra-alveolar period significantly affects the prognosis of pulp in immature permanent teeth after replantation. When the extra-alveolar period is more than 30 minutes, the chance of pulp revascularization after replantation is very low, therefore pulp extirpation should be performed.

Objective: To investigate the role of anaphylatoxin C5a in patients with asthma.  Methods: A prospective study was performed between September 2006 and February 2007. A total of 33 patients with acute exacerbation of asthma and 13 healthy subjects were recruited into the study. The patients with acute exacerbation of asthma were also studied when they returned to the remission state. Levels of lung function, levels of C5a in induced sputum and cell differential count in induced sputum were determined. Results: The level of C5a in induced sputum was significantly higher in patients with acute exacerbation of asthma ［0.85(0.68-2.13) μg/L］ than that in patients with stable asthma ［0.45(0.26-0.88) μg/L, Z=-2.193, P=0.013］; Sputum C5a levels in stable asthma patients were significantly higher than those in healthy controls ［0.14(0.06-0.45) μg/L, Z=-2.141, P=0.015］. The level of C5a in patients with severe exacerbation ［2.21(1.27-9.0) μg/L］ was significantly higher than those in patients with mild exacerbation ［0.34(0.17-0.63) μg/L］ and moderate exacerbation ［0.85(0.55-1.67) μg/L, χ²=12.330, P=0.001］. The level of C5a in induced sputum was positively correlated with the number of total cells count (r=0.797, P=0.004), neutrophils (r=0.504, P=0.032) and macrophages (r=0.424, P=0.036) in acute exacerbation of asthma. Conclusion: C5a levels in induced sputum could be identified as an important prognostic biomarker, which involved in asthma’s pathogenesis.

Objective: To test the hypothesis that in a high-salt induced hypertension in normal rats, whether the changes of intrarenal renin-agiotensin system (RAS) play a critical role in renal damage and could be reflected by urinary angiotensinogen (AGT). Methods: In the study, 27 normotensive male Wistar-Kyoto rats were divided into control group ［0.3% (mass faction) NaCl in chow, n=9, NS］, high-salt diet group ［8% (mass faction) NaCl in chow, n=9, HS］ and high-salt diet with Losartan group ［8% (mass faction) NaCl in chow and 20 mg/（kg·d） Losartan in gavages, n=9, HS+L)］, and were fed for six weeks. The blood pressure was monitored and urine samples were collected every 2 weeks. AGTs in plasma, kidney and urine were measured by ELISA kits. The renal cortex expression of mRNA and protein of AGT were measured by Real-time PCR and immunohistochemistry (IHC). The renin activity and ANGⅡ were measured by radioimmunoassay (RIA) kits. Results: Compared with NS, the systolic blood pressure (SBP) ［(156±2) mmHg vs. (133±3) mmHg, P<0.05］ increased significantly at the end of the 2nd week, and the urinary protein ［(14.07±2.84) mg/24 h vs. (7.62±3.02) mg/24 h, P<0.05］ increased significantly at the end of the 6th week in HS. Compared with HS, there was no significant difference in SBP (P>0.05) but the proteinuria ［(9.69±2.73) mg/24 h vs. (14.07±2.84) mg/24 h, P<0.01］ decreased significantly in HS+L. Compared with NS, there was no significant difference in the plasma renin activity, angiotensinogen and ANGⅡ level in HS (P>0.05), but the renal cortex renin content ［(8.72±1.98) ng/(mL·h) vs. (4.37±1.26) ng/(mL·h), P<0.05］, AGT formation ［(4.02±0.60) ng/mg vs. (2.59±0.42) ng/mg, P<0.01］, ANGⅡ level ［(313.8±48.76) pmol/L vs. (188.9±46.95) pmol/L, P<0.05］ were increased significantly in HS, and the urinary AGT and ANGⅡ excretion rates increased significantly (P<0.05). Compared with HS, the plasma renin activity, angiotensinogen and ANGⅡ level were significantly increased (P<0.05), but the renal cortex renin content, AGT formation, ANGⅡ level significantly decreased (P<0.05), and the urinary AGT and ANGⅡ excretion rates decreased significantly in HS+L (P<0.05). The urinary AGT excretion rates were positively correlated with the AGT level in the renal cortex (P<0.05). Conclusion: Up-regulation of intarenal RAS may contribute to renal damage in high-salt induced hypertension rats. Urinary AGT may reflect the status of intrarenal RAS.

Objective: To investigate the expression of apolipoprotein A-Ⅰ(ApoA-Ⅰ) in eight histological types of renal neoplasms and to explore a new biomarker for differential diagnosis.Methods: The immunochemistry was used to detect the expression of ApoA-Ⅰ in 23 cases of renal tumors, including clear cell carcinoma,papillary cell carcinoma, chromophobe cell carcinoma, oncocytoma,multilocular cystic carcinoma, renal pelvis invasive urothelial carcinoma,metanephric adenoma and collecting ducts carcinoma. Five cases of cancer-adjacent normal tissues were obtained from another five renal tumor patients and were chosen as control group. Results: In the 23 cases of renal tumors, ApoA-Ⅰ was expressed in 21 cases(positive rate was 91.3%).There were only two in five cases of normal tissues which expressed this protein(positive rate was 40.0%).A significant differentiation was observed between the two groups(Z=-2.829,P=0.003). In renal clear cell carcinoma(RCC), ApoA-Ⅰ expression level was correlated with the grade and stage of tumor tissues. ApoA-Ⅰ was stained much more stronger in RCCⅡ-Ⅲ than in RCCⅠ(Z=-2.070,P=0.038).In various histological types of renal cancer, ApoA-Ⅰ was all expressed to some degrees. Conclusion: ApoA-Ⅰ can be chosen as a tumor biomarker to differentiate various histological types of renal neoplasms.

Objective: To investigate the complications of spastic cerebral palsy with selective posterior rhizotomy (SPR).Methods: In the study, 2 593 patients who had undergone SPR from January 2000 to September 2012 were followed-up for at least one year. The complications were classified.Results: Peri-operative complications: pulmonary system complications including bronchial spasm (5 cases, 0.19%) and aspiration pneumonia (4 cases, 0.15%); digestive system complications including abdominal bloating (145 cases, 5.6%) and colic (80 cases, 3.1%); urinary system complications including temporary bladder dysfunction (54 cases, 2.1%) and urinary tract infection (6 cases, 0.23%); peripheral nervous system complications including lower extremity weakness (327 cases, 12.6%) and lower extremity sensory disturbances (140 cases, 5.4%); central nervous system complications including headache (112 cases, 4.3%) and epileptic seizures (4 cases, 0.15%). None spinal or intracranial infection, intraspinal hematoma or intracranial hemorrhage were identified. General surgery complications including back pain (1 382 cases, 53.3%), delay wound healing caused by infection (5 cases, 0.19%) and cerebrospinal fluid leakage (8 cases, 0.31%). Longterm follow-up complications including lower limb decreased exercise capacity (incidence: 7.33%) and lower extremity sensory disturbance (incidence: 5.59%). Urination occurred in only one case and defecation function disturbance with no sexual dysfunction was identified. The incidences of scoliosis, thoracic kyphosis, spondylolisthesis and long-term back pain were 7.23% (31/429), 4.2% (18/429), 10.49% (45/429) and 9.72% respectively.Conclusion: SPR is one of the effective and safe surgical treatments for spastic cerebral palsy. Valid methods should be applied to reduce the incidence of postoperative complications, such as choosing the appropriate patients, meticulously operating in the surgery, assistance of electrophysiological guidance, reinforcing perioperative management and regular rehabilitation training after operation.

Objective: To determine the prognostic factors of primary osteosarcoma in adults. Methods: This is a review of 54 patients older than 40 years (24 men and 30 women) who were treated between 1998 and 2011 at the authors’ institution. Demographic information and follow-up data were obtained and statistically analyzed. Results: Tumors involved the limbs in 30 patients (55.5%) and axial skeleton in 17 patients (31.5%), and arose from soft tissue in 7 patients (13%). And 6 patients (11.1%) had synchronous metastasis. According to our review, tumors were treated surgically in 52 patients (96.3%). Local recurrence was documented in 14 patients (26.9%). Metastasis after diagnosis appeared in 21 patients (38.9%). In the 52 patients who received the surgical treatment, the 5 year disease-free survival and overall survival rates were 43.7% and 50.4%, respectively. Conclusion: Adult patients with primary osteosarcoma had a poor clinical outcome. Inadequate surgical margins, more tumors in the axial location due to high recurrence rates, metastatic disease at presentation, and large tumor volumes were associated with significantly lower survival rates. Aggressive multi-agent treatment regimens might improve survival.

Objective: To compare the efficacy and safety of tubeless percutaneous nephrolithotomy (tubeless-PCNL） and ureteroscopic lithotripsy（URL） in treatment of impacted upper-ureteral calculi ≥1.5 cm in size. Methods:Patients with ureteral stones sized ≥1.5 cm and lodged above the fourth lumbar vertebra who were treated between September 2009 and July 2013 in Peking University People’s Hospital were retrospectively analyzed. In the study, 182 patients underwent tubeless-PCNL or URL treatment respectively, and the operation success rates were compared. The duration of operation, intraoperative blood loss（average hemoglobin decrease）, complications, mean hospital stay and residual stone rates were also compared. Results: Fifty-four patients underwent tubeless-PCNL treatment，the average stone size was (1.9±0.4) cm，nephrostomy tubes were placed in two patients，and the operation success rate was 96.3%(52/54). In the rest of the 52 patients，and the mean operation time was (30.1±14.8) minutes with an average postoperative hemoglobin decrease of (10.2±6.1) g/L, and the mean hospital stay was (3.0±1.4) days. Only one of the patients had residual fragments （2%）. The main complications included minor perirenal hematoma in 1 patient, fever in 2 patients，elevated blood WBC in 11 patients，and analgesics requirement in 3 patients. In the study, 128 patients were treated with URL，the average stone size was (1.7±0.3) cm. 19 procedures failed，and 10 patients were converted to PCNL，extracorporeal shock wave lithotripsy was executed subsequently after double-J stent placement in 5 patients，and migration of calculi or stone fragments happened in 4 patients. The mean operative time was (51.3±25.5) minutes for the remaining 109 patients with a hemoglobin reduction of (5.2±7.2) g/L. The mean hospital stay was (2.9±1.3) days, and residual stones were found in 13 of the 109 patients (11.9%). The main complications included fever in 3 patients, elevated blood WBC in 42 patients, analgesics requirement in 13 patients because of pain in the urethra or flank. The size of the stones between the two group didn’t show significant difference，but the success rate of the tubeless-PCNL procedure was significantly higher. Except that hemoglobin decrease was slightly higher in the tubeless-PCNL group，the mean operative time, the rate of residual stones and rate of complications of the tubeless-PCNL group were lower significantly. Conclusion:  Treating stones above 4th lumbar vertebra larger than 1.5 cm were challenging. It is difficult to treat these stones with URL because of a high probability to fail, but on the contrary, tubeless-PCNL was more likely to be performed successfully. For surgeons experienced with the PCNL technology, treating stones≥1.5 cm with tubeless-PCNL procedure may turn out to be more efficient and with a higher operation success rate, and the risk of complications was lower without lengthening the postoperative hospital stay.

Objective: To evaluate the diagnostic value of fluorine-18 fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) in fever of unknown origin (FUO) in a Chinese hospital.  Methods: The records of 51 patients with FUO (32 men and 19 women; mean age 54 years with a range between 3 and 81 years) were analyzed retrospectively. All the patients were examined by ¹⁸F-FDG PET/CT scan and the results were compared with the final diagnosis which was established by additional procedures including pathology, laboratory examination, and clinical followup for more than 3 months. The t test was used for statistical analysis. Results: A final diagnosis was established for 48 patients, including 32 patients with infectious diseases, 9 with malignancies, and 7 with non-infectious inflammatory diseases. By FDG PET scan alone, the rates of true positive, false positive, false negative, and true negative were 52.9%, 27.5%, 17.6%, and 2.0%, respectively. By FDG PET/CT scan, the rates of true positive, false positive, false negative, and true negative were 70.6%, 27.5%, 2.0%, and 0, respectively. ¹⁸F-PET/CT had a sensitivity of 97.3% (36/37), specificity of 0 (0/14), and accuracy of 70.6% (36/51) in FUO, especially a high sensitivity and accuracy of 100% (9/9) in the diagnosis of malignant tumor. Moreover, the maximum standardized uptake value (SUVmax) in tumor was significant higher than that in infection (3.7±2.7 vs. 7.7±3.5, P=0.001, t=3.6), which implied that SUVmax might be useful in differential diagnosis in FUO. Conclusion: FDG PET/CT is a valuable imaging tool for the identification and location of the potential lesion in FUO and is helpful for the etiological diagnosis, especially in the diagnosis of malignant lesions.

Objective: To study the morphology of middle cerebral artery (MCA) M1 segment. Methods: We selected the MRA data of 794 MCA (400 of the left side and 394 of the right side) from January 1, 2011 to June 30, 2011 consecutively and analyzed the morphology of the MCA M1 segment in axial, anteroposterior and lateral view, measured the length of the M1 segment, and analyzed the similarity of the left and right side M1 segment morphology. Results: In axial, anteroposterior and lateral view, the MCA M1 segment showed C-shape > L-shape > S-shape. In axial view, it was about 373 (47%) M1 segment performance for the C-shape, of which 340 (42.8%) M1 segments showed bowing to the dorsal side, only 33 (4.2%) M1 segments showed bowing to the ventral side. In anteroposterior view, it was about 322 (40.6%) M1 segments of the performance of the C-shape, of which 262(33.0%) M1 segments showed a bowing to the superior, 60 (7.6%) showed bowing to the inferior. The similarity of the left and right MCA M1 segments was 27.2% (114/419) in axial view and 42.7% (179/419) in anteroposterior view. It was more similar in anteroposterior view than in axial view. Along with the increase of age, in the axial view, L-shape converted to C-shape very obviously, but only mildly elevated in S-shape. In anteroposterior view, the L-shape converted to the C-shape or S-shape along with the increase of age. Conclusion: The different morphology of MCA M1 segment in axial and anteroposterior view may be involved in the development of intracranial atherosclerosis.

Objective: To explore a rapid and cost-effective method for identification of Candida glabrata through the comparison of two different methods, using molecular methods of sequencing as gold standard.  Methods: From our clinic, 200 strains of suspected Candida glabrata were collected during the last 3 years and selected after incubation in CHROMagar Candida medium for 48 h. By comparing the results of the CHROMagar Candida medium, the identification of the rapid trehalose test for different kinds of strains were analyzed under incubation in the tubes for 3 h, 6 h, and 24 h at 37 ℃ and 42 ℃, respectively. All the strains were identified to species level by methods of sequencing. The optimal time and temperature of the trehalose test for the identification of Candida glabrata were assessed. Two different methods, CHROMagar Candida medium and the rapid trehalose test, in identification of Candida glabrata were compared. Results: In all the 200 strains, Candida glabrata ferment trehalose with 3 h incubation under 42 ℃ were the optimal time and temperature for fermenting trehalose. The accuracy, sensitivity, and specificity of the rapid trehalose test were 99.00% (198/200), 98.66% (147/149) and 100.00% (51/51). The accuracy rate of CHROMagar Candida medium was 79.50% (159/200), the sensitivity and specificity were only 89.93% (134/149) and 49.02% (25/51), however, compared with the domestic current popular methods, the rapid trehalose test had better time efficiency ratio. Conclusion: The evaluation results suggest that the rapid trehalose test has advantages in terms of operational convenience and low cost, and the results can be obtained in 3 h. Therefore, it has application value in clinical laboratory.

Breastfeeding has been recognized as the most natural and nutritious way of feeding babies. Besides the nutritional, immunological and emotional benefits, breastfeeding promotes a healthy stomatognathic system. First of all, the nutrients and minerals in maternal milk are easy to be absorbed by the infants, which contributes to the mineralization of the teeth, and suppress the propagation of bacteria on the teeth. Though the jury is still out on whether breastfeeding can prevent Early Childhood Caries (ECC), it is definite that we should pay attention to feeding at night and the oral hygiene of the babies. Secondly, the method of feeding is closely bound up with the development of dentition and jaw. Breast-and bottle-feeding involve different orofacial muscles, which possibly have different effects on the harmonic growth of maxilla and dental arches. Meanwhile, breathing, swallowing and mastication should be developing in harmony, and differences exist in the learning of the coordinated movement between breast feeding and bottle feeding children. Bottle feeding had been proved to be closely related with the non-nutritive sucking habits which can cause malocclusion. At last, it should be pointed out that breast feeding should be the only feeding source in the first 6 months of life, then supplementary foods should be added. And prolonged bottle feeding should be avoided. We can see that breast feeding is definitely good for the infants, but the reality is not optimistic in our country.