PLGA/PCL-BMP-2 core-shell nanofibrous composite membranes(PP-B) were fabricated by coaxial-electrospinning. Electrospun PLGA/PCL nanofibrous membranes(PP) were set as control group.The structure of core-shell fibers ,cell proliferation and osteogenic diffrretiation on the two membranes were evaluated.This study confirmed that PP-B nanofibrous composite membranes improved the early osteogenic differentiation of MC3T3-E1 cells in vitro.

Objective: To explore impacts of high-fat diet on stability of silk ligature in combined obesity and ligation-induced periodontitis mouse models. Methods: One hundred and thirty-four mice were divided into high-fat (HFD, n = 77) and low-fat diet (LFD, n = 57) groups to induce obesity and normal-weight control, respectively. After 8, 16 or 30 weeks on diet, all mice were induced periodontitis with silk by one-time ligation for 5 or 10 days. Effects of diet type, duration on diet and ligation duration on ligature detachment were statistically analyzed. Results: The total detachment rate of ligature was 5.97%. The 10-day group had 2 times higher (8.04% vs. 2.50%, P < 0.01) and the HFD group had 4 times higher (9.09% vs. 1.75%, P < 0.05) detachment rates compared with those of 5-day and LFD groups, respectively. Duration on diet had no significant effect on detachment rate. Conclusion: When establishing combined models of diet-induced obesity and ligation-induced periodontitis, high-fat soft diet significantly increases detachment of silk ligature. To reconcile the contradiction between protecting obese condition and increased ligature detachment due to overtime ligation, 10 days’ ligation is an appropriate threshold to stop induction or to change silk ligature.

Objective To explore the polymerization efficacy of dual-cured fluid composite resin cores under different light irradiation conditions. Methods Three types of dual-cured fluid composite resin cores A( DC CORE ONE ), B（MultiCore Flow）and C（Rebilda DC）were filled into organic glass moulds, and then exposed to LED light-curing devices with two different light irradiation conditions, 1 000 mW∕cm2 continual exposure for 20 s and 3 200 mW∕cm2 continual exposure for 6 s. Each group included 6 specimens, with a total of 36 specimens. Nou’s microhardness of surface was detected at 15 min and 24 h post-curing to determine degrees of polymerization. After post-curing for 24 h, specimens were soaked in 100% ethanol for 24 hours and the percentages of reductions of hardness after soaking were recorded to compare cross-link density. Data were analyzed using paired t test and independent t test. Results After 24 hours’ post-curing，three types of materials all displayed increased hardness compared with that of 15 minutes’ post-curing when exposed to the same light irradiation condition, except for Material A, the difference in hardness of Material B and C were statistically significant ( P < 0.05 ). The hardness of the same materials for the same period, when exposed to light irradiation condition of 3 200 mW∕cm2 × 6 s was higher than 1 000 mW∕cm2 × 20 s, apart from Material B and C after 24 hours’ post-curing , the rest materials for the same period under different light irradiation conditions were statistically significant ( P < 0.05 ). After being soaked for 24 h in ethanol, Material B and C showed higher percentage of hardness reductions when exposed to condition of 1 000 mW∕cm2 × 20 s than that of 3 200 mW∕cm2 × 6 s. In contrast, Material A showed higher percentage of reductions when exposed to light irradiation condition of 3 200 mW∕cm2 × 6 s. Conclusion For dual-cured fluid composite resin cores materials, short-time super-intense light exposures conditions are feasible.

Objective　 To investigate the expression of SUZ12 in tongue squamous cell carcinoma (TSCC) and its correlation with clinical pathological parameters, to investigate its significance in TSCC treatment and tumor prognosis. Methods Immunohistochemistry was used to examine the expression of SUZ12 in samples from 72 patients with TSCC and 15 normal tongue mucosa. The associations between SUZ12 and multiple clinicopathological parameters and prognosis were analyzed. Results The expression of SUZ12 was significantly higher in TSCC than in normal tongue mucosa. There were no statistically significant differences between the expression levels of SUZ12 and age, sex, smoking, alcohol use, tumor size, pathological grade and clinical stage (P>0.05). However, its over-expression was correlated with cervical node metastasis(P=0.0325), reduced overall survival rate (P=0.0225) and disease-free survival rate(P=0.0179). Conclusions Our data reveal that aberrant SUZ12 over-expression is associated with cervical nodes metastasis and reduced survival rate in TSCC, suggesting that SUZ12 might serve as a novel biomarker with diagnostic and prognostic significance.

Abstract: Objective To analyze differentially expressed genes of dendritic cells infected with Porphyromonas gingivalis and explore the pathogenesis of periodontitis and to provide clues for future research. Methods High-throughput sequencing was used to analyze differentially expressed genes, gene pools and related functions of in vitro induced dendritic cells under P. gingivalis infection. Results A total of 7305 differentially expressed genes with at least two-fold changes were found in this experiment. The results of gene ontology showed that the biological processes, cell components, and molecular functions of dendritic cells after P. gingivalis infection greatly changed. Gene enrichment analysis showed that the tumor necrosis factor gene set, cytokine and inflammatory response gene set, interleukin 1 and NF-kB family of gene transcription factor, interferon signal gene set, B cell receptor signal gene set, T cell receptor signal gene set enriched significantly. Conclusions Dendritic cells can cause genetic changes after P. gingivalis infection, causing the immune response and inflammatory reaction. The levels and effects of CXCL and SOCS could be the direction of future research.

Objective　 To evaluate clinical effects of CAD/CAM ceramic Endo-onlay restoration in the posterior teeth after root canal treatment. Methods 82 completed endodontically treated posterior teeth from 71 cases, including 33 males and 38 females, aged 20-50 years old, were restored with IPS e.max CAD Endo-onlays.Then the color, shape, fracture , marginal discrepancy, secondary caries and food impaction status were assessed after a 24-month follow-up.Results During the follow-up, 4 were missing among 82 dental restorations, among which 78 met the class A standards for shape and secondary caries. 1 was fractured and 4 appeared to have food impaction, more than 95% were scored grade A. Conclusion CAD/CAM ceramic Endo-onlay has good clinical effect in restoration of endodontically treated posterior teeth.

Abstract: Objective To detect human papilloma virus (HPV) genotypes in oral leukoplakia (OLK) and oral squamous cell carcinoma (OSCC) and its clinical significance. Methods Polymerase chain reaction（PCR）and diversion hybridization technology were utilized to detect 37 kinds of HPV genotypes in oral mucosa exfoliated cells from 30 cases of normal mucosa,103 cases of OLK and 30 cases of OSCC, respectively. Clinicopathological characteristics of all subjects were also analyzed. Results In normal oral mucosa, HPV detection rate was 3.33% (1/30). In OLK, HPV detection rate was 4.85% (5/103). In OSCC, HPV detection rate was 3.33% (1/30). There was no statistically significant difference among the groups (chi-square =0.22, P=0.90 > 0.05). 4 OLK cases were detected with 1 kind of HPV, and 1 case was detected with 3 kinds of HPV. Conclusions Non-invasive sampling with PCR and diversion hybridization technology can be applied to clinically detect HPV genotypes in oral mucosa. The detection rates of HPV in OLK and OSCC are low, and HPV may not be the main pathogenesis factor.

[Abstract] Objective：To compare the differences between periapical radiography (PR) and cone-beam computed tomography (CBCT) in diagnosing root canal treatment (RCT) failure cases. Methods：The radiography data of RCT failure cases were retrospectively analyzed. The differences between PR and CBCT in analyzing the pathogenesis and state of RCT failure cases were compared. Results：A total of 210 RCT failure cases’ PR and CBCT images were collected and analyzed. Under-filling teeth and missed root canals mainly account for the failure in RCT. CBCT could judge the quality of root canal filling and the type of root fracture more accurately. The detection rate of missed root canals of CBCT was 14.8% higher than that of PR, and the detection rate of root fracture of CBCT was 5.7% higher than that of PR. Conclusion：CBCT images were better than PR in analyzing the pathogenesis and state of RCT failure cases, which will offer more significances in root canal retreatment.

Objective To compare the occlusal contact characteristics of two different restoration methods of implant crown and removable partial denture while one single first molar was missing. Methods 15 adults with one single first molar missing were selected as the experimental group, 15 normal dentition adults were selected as the control group. Each patient of the experimental group was restored with implant crown and removable partial denture, then the occlusal contact characteristics (total occlusal force, total contact area, asymmetry index of occlusal force, chewing duration and OT/DT ratio) of each patient of experimental group under three different states (no repair, removable partial denture and implant crown ) werecomparedwith the control group. Each subject was detected with the TeeTester occlusal analyzer during centric occlusion and mastication movement. And SPSS 24 software was used for statistical analysis. Results During centric occlusion,the total occlusal force, total contact area and asymmetry index of occlusal force of the patients with no repair were （48.76±12.82）kg，（317.59±58.47）mm2 and （24.78±7.40）,the results of patients with removable partial denture were （54.36±10.59）kg，（355.81±77.43）mm2，（18.29±8.42）,the results of patients with implant crown were （61.94±12.36）kg,（398.17±83.86）mm2,（17.80±6.69）.During mastication movement, the total occlusal force, total contact area, asymmetry index of occlusal force, chewing duration and T0/Td ratio of the patients with implant crown were （52.14±16.53）kg,（348.08±81.76）mm2,（15.69±9.16）,（0.4072±0.10）s and （1.718±0.26）.The statistical analysis showed no significant difference in occlusal contact characteristics in implant crown, removable partial denture and the control group, but there was significant difference between the patients with no repair and other groups. There was no significant difference in chewing duration and the T0/Td ratio of all groups. Conclusion In the aspect of total occlusal force and contact area, implant crown is better than removable partial denture, closer to natural dentition, and obviously better than no restoration. The total bite force and total contact area during centric occlusion are significantly greater than those during mastication movement, but there is no significant difference in the asymmetry index of occlusal force .

Objective　To evaluate different clinical effects of the minimally invasive surgery techniques combined with CBCT examination and conventional technologies on the extraction of embedded supernumerary teeth. Methods Totally 28 patients with 52 embedded supernumerary teeth were selected from 2013 to 2016 and were randomly divided into the minimally invasive group and the conventional group. Respectively two different methods were used to examine and remove the embedded supernumerary teeth. Information of two groups of patients was recorded, including operative time, postoperative pain, postoperative swelling and postoperative complications. Result The operative time of the minimally invasive group（24.7±7.2）min was shorter than that of the conventional group（33.4±8.1）min；the rates of postoperative pain and postoperative swelling were lower than those of the conventional group，the differences being statistically significant（P<0.005）. The occurrence rates of postoperative complications (adjacent teeth damage，leakage of maxillary sinus or nasal cavity, dry socket and limitation of mouth opening) in the minimally invasive group were lower than those in the conventional group. Conclusion Minimally invasive techniques combined with CBCT examination used in the extraction of embedded supernumerary teeth can shorten the operation time，reduce the incidence of postoperative pain and postoperative swelling; meanwhile，it can reduce the occurrence of surgical compliance.

Objective To measure the occlusion of teeth with wedge-shaped defects and explore the correlation. Methods Following examination from 32 patients, 32 teeth which were the only teeth with wedge-shaped defect in single quadrant were regarded as the experiment group. Also, 34 teeth with no such non-cariouscervical lesions were regarded as the control group. Routine clinical examination method and the t-scan Ⅲ system were used to check the distribution of premature contacts(PC) on the subject teeth, and the t-scan Ⅲ system was used to take a dynamic, quantitative analysis for occlusal contact in centric occlusion, lateral occlusion and protrusion of subject teeth. Results The proportion of the teeth with premature contact (PC) in working side in wedge-shaped defect teeth from two experiment groups（75.0%，70.0%） was much higher than that in their corresponding control teeth （17.7%，18.2%）(P ＜0.05). In working side, the percentages of occlusal force and the occlusal contact strain of wedge-shaped defect teeth were significantly higher than the control teeth(P ＜0.05). Conclusion Dysfunction occlusal force can have relation to the progression of wedge - shaped defects occurring on single teeth.

Periodontitis is closely related with many systemic diseases. In recent years, the relationship between periodontitis and colorectal cancer (CRC) has attracted more and more researchers' attention. Fusobacterium nucleatum (F.nucleatum), one of the most important periodontal pathogen, may be involved in the development of CRC. In this present paper, research advances in relationship between F.nucleatum and CRC is reviewed.

Pain is one of the most common symptoms during orthodontic tooth movement. Many studies have shown that pain has become one of the most important reasons for the interruption of orthodontic treatment. With the increase of patients' comfort requirements, how to monitor orthodontic pain and how to reduce the pain during orthodontic treatment has become the focus of orthodontic researchers. In this paper, the characteristics of pain during orthodontic treatment and the methods of controlling pain caused by orthodontics are reviewed.

Abstract：　After orthodontic treatment, there are still many factors leading to the recurrence of the malocclusion, so wearing retainers is necessary. The common retainers in clinical use are: vacuum-formed retainer and its modification, Hawley retainer and lingual fixed retainer. This article compared the three different types of retainers from three aspects, including retention effects, patients’ acceptability and compliance, and the influence of retainers on periodontal tissues, hoping to be helpful to orthodontists to select appropriate retainers.

Peri-implantitis is a chronic infectious disease that can affect peri-implant tissues such as gingiva and supporting bone, compromising the osseointegration prognosis. Photodynamic therapy is based on the principle that a photosensitizer can be activated by light of a suitable wavelength, producing singlet oxygen and other reactive agents which are extremely toxic to certain cells and bacteria. This article mainly elucidates light sources, photosensitizers and molecular mechanism involved in peri-implantitis treatment.