Objective　Cell sheet technology has been proved successful for multiple tissue regeneration. Our previous study demonstrated that adipose-derived stem cells (ADSCs) can significantly promote the ectopic osteogenic potential of osteoblastic bone marrow mesenchymal stem cell (BMSCs) sheet. Therefore, the purpose of this study was to verify whether ADSCs can promote bony healing potential of BMSCs sheet in calvarial defects in rabbits. Methods ADSCs and BMSCs were obtained from the same donor's inguinal fat and iliac cancellous bone, respectively. BMSCs were cultivated by continuous osteoinduction method for two weeks, and the characteristics of BMSCs sheet were analyzed. Then the combination of ADSCs and BMSCs sheet was transplanted to calvarial defects in rabbits. BMSCs sheet and calvarial defects without any treatment were considered as control groups. Eight weeks after the transplantation, the bony restoration and regeneration were assessed by microcomputed tomography (Micro-CT) scanning and histological analysis. Results BMSCs sheet consisted of multilayer sheets containing a large number of mineralized calcium nodules. After eight weeks of transplantation, compared to control groups, BMSCs sheet with ADSCs increased better bone regeneration as evidenced by the greater density of bone, larger number of newly formed mineralized tissue and greater bone volume / total volume (BV / TV) ratio within the composite constructs. Conclusions The combination of ADSCs and BMSCs sheet can significantly promote bone regeneration in calvarial defects in rabbits, which provides a new way to improve bone healing.

Periodontitis is a chronic infectious disease which can cause the destruction of tooth-supporting structures. It is acknowledged that periodontitis is the leading cause of tooth loss in adults. Recently, emerging evidence suggests that periodontitis can elicit systemic inflammation and adaptive immune response through subgingival microorganisms in the dental biofilm. Hence, periodontitis has been recognized as a potential risk factor contributing to a wide range of systemic diseases. Although the detailed biological mechanisms are still not fully understood, some available studies strongly suggest that a bidirectional link exists between periodontitis and systemic diseases. Both conditions can affect and aggravate each other. This article attempts to summarize the impacts of periodontal disease on systemic diseases and health

Abstract：Objective To investigate the effect of CD24 molecule(CD24) on the osteogenic differentiation potential of stem cells from apical papilla (SCAPs). Methods Lentiviral CD24 ShRNA was used to silence the expression of CD24. Real-time fluorescence quantitative RT-PCR was used to detect the knockout effect of CD24. Alkaline phosphatase (ALP) activity assay was used to detect the ALP activity, which was the early marker of osteogenic differentiation. Alizarin-red staining and calcium quantitative analysis were used to study the potential of SCAPs mineralization in vitro. The expression of osteogenic related genes was detected by real-time fluorescence quantitative RT-PCR, including collagen type I alpha 1 chain (COL1A1), collagen type I alpha 2 chain (COL1A2), bone sialoprotein (BSP), osteonectin (ON) and runt-related transcription factor 2 (RUNX2). The gene expression changes of SCAPs were analyzed. Results Real time RT-PCR result showed that CD24 could be silenced in SCAPs. ALP activity assay showed that the depletion of CD24 inhibited ALP activity. Alizarin-red staining and calcium quantitative analysis revealed that the knockout of CD24 obviously suppressed the mineralization of SCAPs in vitro. Real-time fluorescence quantitative RT-PCR displayed that the depletion of CD24 obviously depressed the expressions of COL1A1, COL1A2, BSP and ON in SCAPs. The RUNX2 expression was repressed in CD24 silenced SCAPs compared with control group. Conclusion The gene silencing of CD24 represses the osteogenic differentiation potential of SCAPs by targeting the RUNX2.

To evaluate the effects of two kinds of injectable gel-like scaffolds with different concentrations on the proliferation of dental pulp stem cells in dental pulp tissue engineering. Methods:Different concentrations of type I collagen and peptide hydrogel scaffolds were prepared, and dental pulp stem cells were inoculated on each group of scaffolds respectively. Cell proliferation was detected by CCK-8 assay; cell number and morphology were observed by staining with dead cells. Results The dental pulp stem cells inoculated with different concentrations of scaffolds all grew well. 1% collagen scaffolds and 0.25% hydrogel scaffolds could promote the proliferation of dental pulp stem cells. The viable cells stained dental pulp stem cells Both scaffold materials at various concentrations grew well, and the number of cells showed an increasing trend with the prolongation of culture time. The cells were fully extended and showed a spindle type.

Objective　 To prepare silk fibroin(SF)/polyvinyl alcohol(PVA) / nano-hydroxyapatite (nHA) scaffold and polyvinyl alcohol(PVA) / nano-hydroxyapatite (nHA) scaffold using 3D printing technology and detect their performances. Methods　3D printing technology was used to print SF/PVA/nHA scaffold and PVA/nHA scaffold. Porosity, morphology, mechanical properties and cytotoxicity of different scaffolds were detected. Results　 ①Under scanning electron microscope, SF/PVA/nHA scaffold had regular scaffold structure and clear network structure, exhibited continuous communicating branch, well-connected overlap joint, and uniform scaffold space. Under the same multiples, the network structure continuity of PVA/nHA scaffold was poorer. ②Compressive mechanical properties: Under the same stress(10 Mpa), the strain of SF/PVA/nHA scaffold was larger than that of PVA/nHA scaffold. ③The pore size of group SF/PVA/nHA scaffold was significantly larger than PVA/nHA scaffold. ④Cell toxicity detection: The deformation of SF/PVA/nHA scaffold ,under the same stress(10 MPa),was larger than PVA/nHA scaffold. There was no significant difference in cell appreciation rate between two groups of scaffolds at different time points. Conclusions　3D printing SF/PVA/nHA scaffold and PVA/nHA scaffold hold good physicochemical performance and cytocompatibility.

Objective　To evaluate the effect of silicon coating prepared by sol-gel self-assembling on instant bond strength of zirconia ceramic and resin. Methods　56 zirconia ceramic slices were obtained and randomly divided into 4 groups based on the surface treatment to be applied: groupA: silane couple agent; group B: sol-gel impregnated with 1 layer of silicon coating and silane couple agent; group C: sol-gel self-assembly 2 layer silicon coating + silane coupling agent; group D: sol-gel self-assembly 3 layer silicon coating and silane couple agent. 56 photo-cure composite resin columns were prepared and bonded on the zirconia ceramic by resin cement. Bonded specimens received shear bond strength testing after 24-hour water storage. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were used to characterize the zirconia of different surface treatments, and the sample fracture mode was recorded by the stereoscopic microscopy. Results　The shear bond strength values of group A, B, C, D were respectively (3.05±0.26) MPa, (6.83 ±0.33) MPa, (10.51 ± 0.58) MPa and (7.72±0.35) MPa. There was no statistical difference between group B and group D, while all the other groups were statistically significant (P=0.000).The shear bond strength obtained by self-assembly of two silicon coatings was the largest. Conclusions　Sol-gel self-assembled silicon coating can improve the adhesion strength of zirconia ceramics. The result of sol-gel self-assembling 2-layer silicon coating group is the best.

Objective　 To investigate the effect of interactions between starch，sucrose and HFCS on the cariogenicity of streptococcus mutants. Methods　 Streptococcus mutants UA159 was cultured in BHI medium containing two or three kinds of sugar——1%starch，sucrose，and HFCS ，with the single sugar source used as control. The pH of each culture was measured to assess acidogenicity. Crystal violet assay was employed to determine the ability of adherence. Results　 The pH in sucrose+HFCS and sucrose+starch+HFCS media was decreased faster than that in sucrose+starch and starch+HFCS media( p<0.05). The adhesion of S. mutans in sucrose+starch media was significantly higher than that in other media (p < 0.05). The group containing three sugars has better adhesive ability compared with sucrose + HFCS. The adherence in starch+HFCS media was significantly weaker than that in other media (p < 0.05). Conclusions　 The interaction between starch，sucrose and HFCS can affect the formation of acid，adhesion and biofilm of S.mutants, resulting in the change of cariogenicity.

Objective　 To fabricate and assess the PLGA/HA/BAG composite membranes as a brand-new control-releasing delivery system in treatment of periodontitis. Methods The PLGA/HA/BAG composite films were synthesized by a solvent-evaporation method. SEM was utilized for the morphology and mass loss during the immersion, ion release and changes in pH were also analyzed. The immersion of the films and pristine BAG powder were extracted, between which the efficiency of antibacterial effect was compared with MTT assay. CCK-8 kit was employed to evaluate the cytotoxicity with human periodontal ligament fibroblast cells. Results The film had longer antibacterial effects against Porphyromonas gingivalis (ATCC 33277) and Actinobacillus actinomycetemcomitans (ATCC 29523) than powder. Conclusion The film has great potentials of being a treatment for periodontitis in the future.

Objective: To study the DI value and ploidy distribution of oral squamous cell carcinoma (OSCC) by ICM-DNA quantitative analysis system, and to evaluate its relationship with clinicopathological factors of OSCC. Methods: 79 paraffin specimens of OSCC were collected as experimental group, 25 cases of normal oral mucosa tissue and 30 cases of oral mucosa epithelial dysplasia as control group.ICM-DNA quantitative analysis was carried out after Feulgen staining. Results: 79 cases of OSCC in the aneuploidy occurrence rate was 55.7% (44/79), were significantly higher than the control group of 0% normal tissues (0/25) and oral mucosa epithelial dysplasia (14/30) 46.7%, P =0.000; Compared with mild , moderate and severe three groups of oral mucosa epithelial dysplasia , the rate of aneuploidy occurrence was 0 % ( 0 / 2 ) , 14.3 % ( 1 / 7 ) , 61.9 % ( 13 / 21 ) , P = 0.036 , respectively ;high and moderate-poor differentiation between the three groups, aneuploidy occurrence rate of high differentiation group at the rate of 42.5% (20/47) lower than the moderate-poor differentiation group was 75% (24/32), P =0.004; lymph node metastasis group have 78.6% aneuploidy occurrence rate (22/28), higher than that without lymph node metastasis 43.1% (22/51),P =0.002.The incidence of aneuploidy was not associated with age (P=0.193), sex (P=0.232) ,smoking (P=0.151) and the location of the disease (P=0.915). Conclusion: DNA aneuploidy rate of OSCC was higher than that of normal tissue and epithelial dysplasia of oral mucosa, and may be associated with the degree of differentiation and lymph node metastasis .ICM-DNA quantitative analysis provides a valuable clinical indicator for the diagnosis of OSCC and the judgment of malignancy ,which is expected to be used for adjuvant clinical prediction and the diagnosis of OSCC

Objective To investigate the method of determining the occlusal plane front point of complete denture and the photoelastic effect. Methods The study time was from February 2015 to July 2017. 10 patients with dentition defect diagnosed and treated in our hospital were selected as the research objects. The occlusal plane anterior point of the complete denture was determined by the Gothic arch apex(A group) and natural trajectory bite(B group). The denture occlusal index, photoelastic effect and stress were recorded and detected. Results Before the occlusal adjustment, the occlusal contact time in A group was more than B group, while the percentage difference of occlusal force between left and right sides, the distance from the center of the occlusal force to the center line were less than B denture group, and there was statistical significance (P＜0.05). After occlusal adjustment, the above indexes were compared between the two groups, while there was no statistical significance (P＞0.05). The angle between the working angle of the cusp and the occlusal plane in the two group showed tendency of going farther. The adjacent angle difference also had the tendency to increase in the far distance, and there was no significant difference between the two groups (P＞0.05). The light elastic materials of A group and B group were all to meet the basic requirements of model experiment. Lingual concentrated jaw centric occlusion and anterior occlusion of two groups were less than the maximum stress value of anatomic occlusal (P＜0.05), and there was no difference between the two groups (P＞0.05). Conclusion The Gothic arch vertex and natural trajectory bite which determine the occlusal plane anterior point of complete denture can maintain the denture occlusal balance, and the Gothic arch vertex which determines the occlusal plane anterior point can achieve better occlusal relationship.

It is difficult to fix the missing teeth in Papillon-Lefevre Syndrome(PLS) patients. PLS patients usually lose most of teeth early. The absorbed alveolar ridge is constrictive and the retentive force is weak in the overdenture of PLS patients. This paper reported one PLS case with the loss of the majority of teeth using magnetic attachment supported overdenture. After the restoration, the PLS patient’s denture function is good and the retentive force is strong. It suggests that magnetic attachment supported overdenture used in PLS patients with the loss of the majority of teeth is successful.

Objectives To track patients after mandibular cyst fenestration with the application of plugger device, and to explore the relationship between the frequency of flushing and reduction in cyst diameter.Methods 47 mandibular cyst patients who had fenestration surgery were included in the sample. The patients were divided into two groups according to the number of flushing: Group A flushed≦ 2 times/day, Group B ≧ 3 times/day. The reduction in cavity size was measured from panoramic radiographs and classified into as follows: effective - the maximum diameter of the cyst reduced by ≥50%; improvement - the maximum diameter of the cyst reduced by <50%; no change or increase in size. Data analysis was conducted by chi-square test.Results In the A group, there were 8 cases of effectiveness, 10 cases of improvement, and 4 cases of no change or increase in size. In the B group, there were 18 cases of effectiveness, 5 cases of improvement, and 2 cases of no change or increase in size. The effective rate of group A was 36.4% and in group B it was 72% (χ2=6.01, P<0.05). Conclusions There is a significant relationship between daily flushing times and cyst size reduction. Patients who are flushed more than 3 times/day have a greater reduction.

Objective To evaluate the relationship between the depth of the curve of Spee and dental arch morphology. Methods 150 Uygur adults(62 males and 88 females) between the age of 18 and 25 were selected and divided into two groups. Dental casts of all subjects were taken.By means of computer software, the depth of the curve of Spee, the width of the cusp tips of the canines, the width of the cusp tips of the molars and the length of dental arch were measured. Results The depth of the curve of Spee was not affected by sex，there was significantly statistical difference between the depths of the left and the right curve of Spee of the identical individual. Dental arch morphology was affected by the gender factors, but not influenced by the depth of the curve of Spee. Conclusion In clinical practice, the depth of the curve of Spee can be used as a reference plane for occlusal reconstruction and orthodontic treatment.

Abstract： Objectives To observe the clinical effects of intentional replantation on treatment of refractory periapical periodontitis of a mandibular molar. Methods A lower second molar with refractory periapical periodontitis was extracted. The tooth apical and the socket were curetted, immediately followed by replantation of the tooth and fixation. Results Two weeks after the surgery, the soft tissues showed minimal inflammation and the fistulous tract was resolved. Four weeks later, the tooth remained clinically asymptomatic and after three months the tooth was almost stable. Six months later, the tooth clinical examination was normal and new bone was observed in the alveolar socket. Conclusion Intentional replantation is an effective treatment option for those teeth with refractory periapical periodontitis when periradicular surgery or dental implant is not feasible.

Chondroblastoma is a rare osseous tumor, whose incidence is less than 1% in all primary bone tumors. It is also a benign cartilaginous tumor, which affects the epiphyseal regions of the tubular bones. The tumor occurring in the head and neck region is uncommon. This paper reported one case about the primary condylar chondroblastoma and reviewed the relevant literature to discuss the radiographic features.

As a part of periodontal plastic surgery, the soft tissue augmentation procedure is widely used to augment the keratinized gingiva or mucosa around teeth and implants to enhance periodontal defense and prevent further recession. At present, the most commonly used soft tissue augmentation procedures include free gingiva graft (FGG), subepithelial connective tissue graft(SCTG)and bilaminar techniques. The main donor site for a connective tissue graft is the hard palate. So a detailed understanding of the anatomy, histology and thickness of hard palate is crucial to a successful surgery. This article reviews the anatomy and thickness of the hard palate to provide some guidance of surgery design, risk assessment and prognosis.

Tumor necrosis factor-α is a monocyte factor involved in the inflammatory response in vivo and can promote osteoclast formation under the combined action of Receptor activator for Nuclear Factor-κ B Ligand.Orthodontic tooth movement is the process of periodontal tissue and bone remodeling under mechanical stress, which requires osteoclast and osteoblast and other periodontal factors. During orthodontic treatment, under the influence of orthodontic force, periodontal tissue will be in a state of mild inflammation, and various inflammatory factors produced can promote periodontal tissue remodeling. Tumor necrosis factor-α plays an important role in orthodontic tooth movement and can promote osteoclast formation, and also has some effects on the formation of osteoblasts. This review summarizes the progress in the study of the role of TNF-α in orthodontic tooth movement.

Dental implantation has become an important way to repair dental defects and the biological activity of implant surface has an important influence on the success rate of implantation. With the development of bionics and nanotechnology, more and more scholars hope that the surface of the implant can be further micrometer or nano treated on the basis of conventional sand blast etching, to construct a more bio-active implant surface. After combing the methods of building surface structure of implant at home and abroad, methods of micronization on the surface of implants is classified into one kind, while methods of nanocrystallization on the surface of implants is classified into another kind. Experimental methods, effects on osteogenesis and the principles of action of the two classification will be compared in order to provide the basis for further studies.

The distal wedge procedure is an approach of periodontal flap surgery, mainly used to eliminate periodontal pockets on the distal surface of terminal molars, it is also used to eliminate deep periodontal pockets in edentulous areas.This procedure is widely used for the advantages on providing access for osseous defect in the maxillary tuberosity and the mandibular retromolar pad which have special tissue type and anatomical structure.This article will discuss the techniques and clinical application of the distal wedge procedure.