Compared with the 1999 classification system of periodontal diseases, many changes have taken place in the new international classification of periodontal diseases and peri-implant diseases in 2018.The matrix based on stage and grade to appropriately define periodontitis in an individual patient was proposed which especially got the attention of the periodontists at home and abroad. This paper briefly introduces the background, content and clinical significance of this matrix based on stage and grade, and puts forward the application steps of it according to the national conditions of China.

Objective: study the synergistic effect of coadministration of vascular endothelial growth factor-165 and platelet-derived growth factor-bb in the early stage of angiogenesis. Method: we made an incision with 1.5-2.0cm in the abdomen of Sprague-Dawley rat and then VEGF mix BMSC cell sheet(group V);PDGF mix BMSC cell sheet(group P); VEGF and PDGF mix BMSC cell sheet(group V+P) and BMSC cell sheet(group D) were transplanted to the subcutaneous of abdomen respectively.Through RT-PCR study the angiogenesis related geng expression and use histology method to calculate the vascular area,diameter,and quantity. Result: angioma like vessel has seen in V group at 2 week after surgery.V group also has aggressively larger vessel diameter than the other group. VP group has relatively more mature vascular,gene sxpression,and vascular quantity at any point of time.But V group,P group,and D group has no statistical significant in gene expression and vessel diameter,area,and quantity between the two time point.Conclusion: Coadministration of VEGF and PDGF with BMSC can promote vascularization in vivo.This result can help the research of tissue engineering in the future.

Objective To investigate the effects of porphyromonas gingivalis (Pg) on polarization of bone marrow-derived macrophages (BMDMs) in db/db mice. Methods Pg was used to stimulate BMDMs from wild type C57BL / 6 or db/db mice, the expression level of M1 and M2 gene markers was detected. The relative expression levels of Tnf-α, Il-12, Arg1, Ym1, Fizz1 and Mrc1 were detected by qRT-PCR. Results Compared with wild type mice, there was no statistically significant difference in the effect of Pg infection or not on BMDMs expressing Arg1, Fizz1 and Mrc1 in db/db mice under IL-4 induction; however, the expression of Ym1 in BMDMs of db/db mice was significantly decreased, while no significant difference was found in Tnf-α, and the expression of il-12 was markedly decreased. Conclusion The ability for Pg to switch from M2 to M1 was weakened in BMDMs of db/db mice.

Objective　The effects of four surface treatment methods and the depth of root canal on the adhesive strength of glass fiber posts were compared. Methods　25 single-root premolars were randomly divided into five groups after conventional root canal therapy.Surface treatment of 25 popo Fiber piles:group A(untreatedl ),group B（H2O2），groupC（ silanization），group D（HF），group E（sodium ethoxide）.he fiber post was bonded into the isolated root canal and made into thin pieces. According to the depth of root canal, the specimen was divided into three subgroups: upper root, middle root and lower root，and use Microlaunch test to test bonding strength.Observation of the appearance and Morphology of Fiber piles in each Group under scanning Electron Microscopy. Results　The adhesive strength of fiber posts is :group B>group D>group E>group A,and the differences among groups are significant（P<0.05）.There was no significant difference between group C and group A(P>0.05). The bonding strength of fiber pile at different depths of root canal is as follows: upper root> middle root >lower root.Sem observation showed that the surface morphology of the treated groups was higher than that of the control group.Conclusions　H2O2,HF and sodium ethoxide can significantly improve the bonding strength of glass fiber posts;With the increase of root canal depth, the adhesive strength of fiber posts decreases gradually.

objective to study the feasibility of tooth differentiation induced by embryonic stem cells. Methods embryonic stem cell differentiation was induced by ameloblast serum-free conditioned medium (ASF-CM), morphological changes were detected, gene expression and immunophenotype were detected in vitro. Results After treated with ASF-CM, cobblestone-like cells, which resembled dental epithelial cells, were observed at the periphery of the plated mEBs. at the same time, the induction of groups of cells can detect CK14, AMBN and AMGN mRNA expression, DMP1 and DSPP expressing negative, further analysis showed the immune phenotype of embryonic stem cells induced group expression CK14, AMBN AMGN and positive. Conclusions the embryonic stem cells were transformed into odontogenic epithelial cells by using the signal molecules secreted by ameloblast serum-free conditioned medium in vitro to simulate the epithelial microenvironment.

Objective　 To investigate the expression of PIGK and PCNA in ameloblastoma and evaluate its relationship with the expression of PIGK and PCNA. Methods　 The expressions of PIGK and PCNA in 45 patients with ameloblastoma were detected by immunohistochemical staining method and HE staining. Statistical analysis was performed to analyze the relationship between the staining markers and pathological types and the correlation between the markers. Results PIGK was positive in 3 cases and was not associated with the pathological type in ameloblastoma (p>0.05). PCNA was positive in all cases and was also not associated with the pathological type in ameloblastoma (p>0.05). Meanwhile, there existed non-relationship in expression between PCNA and PCNA due to the limited cases. Conclusion　 There is no correlation between the immunohistochemical staining results of PIGK and PCNA and pathological types in ameloblastoma. In addition, there is no relationship between two markers.

Objective To establish a three-dimensional finite element model of the mandibular first premolar wedge-shaped defect and different material inlay restorations, and carry out stress analysis to provide a theoretical reference for clinical inlay restoration of wedge-shaped defects. Methods The raw data of the tooth were obtained by CBCT scanning. The wedge-shaped defect model and the three-dimensional finite element model of the mandibular first premolar were established by Mimics 17.0 and Geomagic Studio 13.0 software, and respectively treated with the resin inlay (A), porcelain inlay (B) and the gold alloy inlay (C), and the undefended wedge-deficient model was used as the control group. Then the stress analysis of the tooth neck was performed using Abaqus 6.14 finite element software. Results From the stress distribution, there were two stress concentration areas in the residual tooth structure and the inlay restoration model after the vertical load wedge defect. The main stress of the remaining tooth body tissue model after wedge deficiency was concentrated in the wedge defect. The main stress of the inlay restoration model was in the neck of the tooth. It was found that the maximum principal stress values of the inlays of different materials were significantly reduced. Conclusion The inlays of different materials can repair the wedge-shaped defect and improve the stress concentration near the defect. The porcelain inlay (B) and the gold alloy inlay (C) are ideal compared with the resin inlay (A).

Objective　The purpose of this study is to compare the effects of cavity preparation between Er:YAG laser and conventional burs on extracted human teeth. Methods　A total of 32 extracted human premolars were used for this experiment.The teeth were randomly divided into 2 groups for cavity preparation,filling and curing:The control group—Cavity preparation with high speed handpiece;the experimental group—Er:YAG laser.All the samples were fillded with the resin.8 samples were randomly selected from the control group and the experimental group.Nano-leakage was observed under scanning electronmicroscopy and statistically analyzed.Independent samples analyze the micro-tensile strength. Results　Scanning electron microscopy showed that there was almost no nano-leakage between the dentin and the filling in the experimental group, and a nano-leakage band was formed between the dentin and the filling in the control group.The bond strength( MPa)of experimental and control group was 26.53±3.61 and 16.10±4.91 respectively. Conclusions　Nano-leakage occurred in all adhesives but it appeared was more serious in the control group.The Er:YAG laser group had higher micro-tensile strength.

Abstract：　Objective　To evaluata the effect of the application sequence of CPP-ACP pretreatment on bond strength of deciduous dentin and tubule occlusion . Methods　56 fresh and not crack primary molars were randomly selected and the enamel of tooth surface was grinded to form the dentin plane．48 primary molars were randomly divided into 3 group(n=16).Group A was etched with 35% phosphoric acid for 15 s.Group B wree treated with CPP-ACP. Afterward,these groups were etched with 35% phosphoric acid for 15 s.Group C were initially etched and then treated with CPP-ACP.In each group, samples were equally distributed into two subgroups (n = 8)to bond with either Adper Single Bond 2 (SB) or Prime&Bond NT(PB).The shear bond strengths (SBS) were tested .Remaining 8 primary molars were prepared to evaluate tubule occlusion prior to bonding using SEM. Results The shear bond strengths (SBS) shows there was no significant difference among the three groups of AN,BN,C（P>0.05). And there was also no significant difference among the three groups of AS,BS,CS（P>0.05).Group AN＞group AS，group BN＞group BS，group CN＞group CS，the difference was statistically significant( P＜0.05).However, the effective dentine tubule occlusion was observed in the CPP-ACP group after acid etching.Conclusions　CPP-ACP treatment of deciduous dentin after acid etching did not affect the bond strength of NT and SB2,and the effective closure of dentin tubules can be realized.The adhesive strength of Prime&Bond NT (NT) is higher than that of Single bond 2 (SB2).

Objective To investigate the expression of nuclear receptor coactivator 7 (NCOA7) in oral submucous fibrosis (OSF) and explore its effect on epithelial to mesenchymal transformation (EMT). Methods 30 cases of OSF tissues, and 15 cases of normal tissues were collected. The protein expression level of NCOA7 and Vimentin in OSF tissues was determined by immunohistochemical (IHC) method. NCOA7 protein and epithelial-mesenchymal transformation related proteins (E-cadherin, Vimentin) in arecoline-treated HOKs were detected by western blot. Results NCOA7 was highly expressed (P<0.05) in OSF tissues at protein level compared to normal oral mucosa. Epithelial basal cells showed a higher vimentin expression in OSF tissues. After 24 hours of treatment with different arecoline concentration, aberrant expression of NCOA7, E-cadherin, vimentin and α-SMA were found in a dose-depended manner. Conclusion Overexpression of NCOA7 was found in OSF tissues and arecoline stimulated epithelial cells and EMT process was found play a role in the pathogenesis of OSF. NCOA7 might be a new therapeutic target for OSF.

Objective　To investigate the application of Foley pressurized water sac in the operation of zygomatic arch fractures, and to evaluate and analyze its clinical advantages. Methods A total of 37 patients with zygomatic arch fractures were treated with a small incision in the vestibule and fixed with Foley's pressurized water sac support. There was no need to operate fixation by additional titanium plate. The advantages and disadvantages of this method were evaluated by the patient’s facial symmetry and opening degree. Results In 37 patients, Foley pressurized water sac was used to treat the zygomatic arch fracture with good postoperative shaping effect and with basic facial symmetry, basically normal mouth opening, slight side reaction, and a cure rate of 97.3%. In addition, it was convenient for the patients to remove the water sac after surgery, and no further trauma was caused. Conclusion The treatment of zygomatic arch fracture with Foley pressurized water sac is a novel and effective treatment method. It has the characteristics of significant postoperative effects, simple operation, high patients’ satisfaction and economy and practice.

Objective To observe the clinical effect of anterior incisional margin or angle defects repaired with resin on enamel shoulder．Methods A total of anterior teeth with different degrees were selected from 2017/9 to 2018/4. 98 anterior teeth in 60 patients were randomly divided into 2 groups, 49 teeth in each group. In the experimental group, the teeth were repaired by resin after preparation of enamel shoulder. And the control group was restored by resin after preparation of enamel short bevel. The restoration rates of two groups were observed and compared after 3-month, 6-month and 1-year follow-up. Results After 3 months, the difference in the repair success rate between the experiment group and the control group had no statistical significance (P>0.05). The repair expulsion rates in the control group were obviously higher than those in the experiment group after 6-month and 1-year follow-up, and the differences had statistical significance (P<0.05). Conclusion The clinical efficacy of restoring anterior incisional margin or angle defects by resin after preparation of enamel shoulder can lower tooth injury and postoperative complications．

Objective: To investigate the clinic effect of root amputation of maxillary molar with residual crowns for caries, guiding clinical work. Methods: After informed consent, 30 maxillary molar residual crown resulting from caries were selected. As for every tooth, the amputation of one root or two was performed, and root canal treatment plus periodontal therapy was done. The prognosis was evaluated 3 months and 6 months after the amputation. Result: 6 months later, the amputation of 28 teeth was successful. One tooth failed due to root fracture, and another due to periodontal abscess. Conclusion: Root amputation of maxillary molar residual crown for caries can be effective.

Chronic periodontitis(CP)is a chronic inflammatory and destructive disease occurring in periodontal supporting tissues. Periodontitis not only affects oral health, but also is closely related to general health. Chronic kidney disease is considered as a non-communicable chronic disease that seriously endangers life and health. In recent years, it has been found that there is a close relationship between chronic periodontitis and chronic kidney disease. This article will review the research progress on the correlation between chronic periodontitis and chronic kidney disease.

Nickel-titanium root canal instrument is a kind of root canal instrument processed by special nickel-titanium alloy. It is widely used in clinical root canal preparation due to its excellent flexibility, root canal forming ability and advantages of saving time and labor.In clinical use, nickel-titanium root canal instruments are typically sterilized using autoclaving when reused. In recent years, the influence of autoclave sterilization on physical properties of nickel-titanium root canal instruments has attracted much attention. In this paper, the research progress on the surface topology, fatigue resistance, cutting efficiency and autoclave sterilization and thermoelasticity of nickel-titanium rotary instruments is reviewed in order to provide reference for clinical use.

Hippo pathway plays as an evolutionarily conserved protein kinase cascade pathway, among which TAZ/YAP is the core effector molecules in this signaling pathway. Many studies have shown that YAP and TAZ are highly related with the occurrence and development of most human malignancies, and its abnormal activation can promote tumor cell proliferation, invasion and metastasis, enhance chemotherapy resistance and obtain stem cell properties. Recent studies indicate that TAZ/YAP are essential for cancer initiation or growth of most human cancers. Recent research findings show that the Hippo-TAZ/YAP signaling pathway is closely associated with the development and progression of HNSCC and inhibition of the activity of this pathway may become a new method for the treatment of HNSCC. This article reviews the latest progress of the Hippo pathway, focuses on the regulation of Hippo-TAZ/YAP signaling pathway in HNSCC, and provides new ideas and strategies for HNSCC research and treatment.

Being adjacent to mandibular second molars, most of fully impacted mandibular third molars often lead to distal bone defect of adjacent second molars after extraction, which is often manifested and aggravated by the original bone defect before extraction. Also symptoms of mandibular second molars may occur, such as formation of periodontal pocket, distal root absorption, erosion and even looseness of second molar resulting in extraction. So it is of great significance to repair the distal bone defect of second molar, which is affected by many factors, such as age, pre-operative impacted state of third molar, and the surgical methods. At present, there are various prevention and repair methods for different influence factors of the distal bone defect of second molar, such as bone/bone substitute graft, guided bone regeneration, and cell active ingredient transplantation etc. But all the existing repair methods have deficiencies, such as high economic costs, or leading to bone resorption and reducing the amount of new bone formation. This ?review? aims? to? summarize? the? research? progress ?on? the influence factor, prevention and repair methods of distal bone defect of adjacent second molar after extraction of fully impacted mandibular third molars.

Nonalcoholic fatty liver disease is a common chronic liver disease that can cause liver lesions of varying degrees, from steatosis, nonalcoholic fatty hepatitis to fibrosis, and eventually cirrhosis and hepatocellular carcinoma. Many studies have shown that systemic inflammation and gut microbiota imbalance may be involved in the occurrence and development of this disease. As a local bacterial infectious disease, periodontitis may regulate the body through periodontal pathogenic bacteria and inflammatory mediators and affect the health of liver. This article reviews the current studies on the correlation between periodontitis and non-alcoholic fatty liver disease, expecting to provide a new prevention strategy from dental science viewpoint for NAFLD.

Abstract：MTA (Mineral Trioxide Aggregate) is a widely used retrograde filling material in endodontics.It not only has good biocompatibility,good sealing ability,but also is antibacterial and hard tissue conductive.But it has two weeknesses:long setting time and inconvenience in operation.In recent years, there are a lot of studies of new fast setting calcium silicate-based retrograde filling materials aiming to shorten the setting time of MTA. This paper is a review on progresses in these new retrograde filling materials.

Cyst plug is a common adjuvant therapy appliance in odontogenic systs decompression. In recent years, with the development of materials and technology, different kinds of cyst plugs are emerging. This review focuses on the application of cyst plug in odontogenic cysts decompression, including the categories, the production methods, as well as the indications, and explores the advantages and disadvantages of all kinds of cyst plugs in the preparation and application. It suggests that the usage of cyst plug after odontogenic cysts decompression is necessary, and it plays an important role in improving the living quality and the compliance of the patients. So far there is no constant standard for the production methods of cyst plug, thus settled guidance should be discussed and then established.