Objective To investigate the photothermal properties of two different new types of photothermal conversion agents and the difference in their effects on oral squamous cell carcinoma in vitro treatment, and provide a material basis for photothermal therapy of oral squamous cell carcinoma. Methods Hydrophilic ultrasmall Cu2-xS nanoparticles (Cu2-xS NPs) and Fe3O4 nanoparticles (Fe3O4 NPs) were synthesized. The temperature changes of Cu2-xS NPs and Fe3O4 NPs were monitored throughout heating and heatingcooling process. The viability of OSC19 cells was recorded by microplate reader. Results Cu2-xS NPs and Fe3O4 NPs were successfully synthesized; under NIR laser, the temperature of both agents’ solution increased, while the temperature of Cu2-xS NPs solution increased more obviously, and the heatingcooling cycles of them were stable. Cu2-xS NPs and Fe3O4 NPs had no obvious cytotoxicity, and could reduce the viability of OSC19 cells to 35.35% (Cu2-xS NPs) and 50.76% (Fe3O4 NPs). Conclusion Cu2-xS NPs and Fe3O4 NPs have excellent photothermal effects and biocompatibility. They can be used for in vitro photothermal therapy of oral squamous cell carcinoma. The effect of Cu2-xS NPs on the in vitro photothermal therapy of oral squamous cell carcinoma is stronger than that of Fe3O4 NPs, which may provide a material foundation for photothermal therapy.

Objective To study the pore characteristics and biological properties of porous magnesium and magnesium alloy scaffolds. Methods Porous magnesium and magnesium alloy with different architectures were obtained by the method of template replication, NaCl particles of different shapes were used as space-holder particles. The effects of micro-architectures on pore characteristics, mechanical properties, degradation behavior and cell adhesion were compared and analyzed by scanning electron microscopy (SEM), X-ray tomography (micro-CT), compressive tests, hydrogen evolution tests, immersion tests and direct cell culture tests. Results SEM and micro-CT results showed that the spherical pore structure had better interconnectivity. The intermetallic compound could significantly improve the mechanical properties of micro-architecture. The hydrogen evolution rate of porous magnesium scaffolds with larger specific surface area and lower porosity was faster. The results of scaffold-osteoblasts co-culture showed that the rapid degradation of micro-architectures was not conducive to cell adhesion and survival. Conclusion The interconnectivity, degradation rates and mechanical properties of Mg-based scaffolds can be modulated by adjusting the micro-architectures, whose implement performance is controllable.

ABSTRACT Objective: To explore the influence of Sonodynamic therapy( SDT) produced by ultrasound( US) combined with the sensitizer hematoporphyrin monomethyl ether( HMME) on biological activity and membrane structured of dental plaque bacterial biofilm. Methods: Collecting bacterial samples from patients with periodontitis and incubate at 37 ℃, anaerobic( 85% N2, 10% CO2, 5% H2). Groupsing: 1. HMME minimum inhibitory concentration: HMME with concentration 0 ?/ml, 10 ?/ml, 20 ?/ml, 30 ?/ml, 40 ?/ml, 50 ?/ml, 60 ?/ml is divided into 7 groups; 2. SDT efficacy: Control groups, HMME groups( 50 ?/ml, minimum inhibitory concentration), US groups, SDT groups. Detection: The minimum inhibitory concentration of HMME in the dental plaque at the ultrasonic intensity of 3 W/cm2 and the time of 5 min; colony-forming units( CFU) of dental plaque under SDT; plate count method was used to detect the survival rate of bacteria; the activity of plaque bacterial biofilm; the change of morphological structure. Results: 1. When the intensity of ultrasound is 3 W/cm2, 5 min, the minimum inhibitory concentration of HMME as a sound sensitizer is 50 ?/ml, and the dose-effect relationship is significant (P<0.05). 2. In the comparison of bacterial biofilm survival rate, the SDT groups were much lower than the other groups (P<0.05). 3. Compared with the morphology of the plaque bacteria in the Control groups which is clear, the bacteria is concentrated and the tubular structure is intact, the plaque bacteria in the SDT groups are damaged, scattered, and the structure is no longer complete. 4. Compared with Control groups, HMME groups and US groups, the plaque bacterial biofilm in SDT groups had a larger proportion of dead bacteria. Conclusions: SDT has a certain bacteriostatic effect on plaque bacterial biofilm. During the process of bacteriostasis, the proportion of dead bacteria increases, and the structure of bacterial biofilm is destroyed, resulting in a killing effect.

Objective To investigate the level of autophagy and apoptosis of ameloblasts in rats with different degrees of fluorosis, and to explore the effect of autophagy on the ameloblast apoptosis in rats with chronic fluorosis. Methods Forty-eight Wistar rats of 4-week-olds were randomly divided into 6 groups to establish a fluorosis rat model by adding 75 mg/L or 150 mg/L fluoride to the drinking water, and an autophagy inhibition model treated with an intraperitoneal injection of 10 mg/kg 3-methyladenine (3-MA). The morphology and expression of Beclin1, p62, LC3, and Cleaved Caspase-3 in rat incisor ameloblasts were observed, and statistical analysis of quantitative results of immunohistochemistry was performed using SPSS 22.0 software package. Results With the increase of fluoride in drinki ng water, features of dental fluorosis became more obvious and found disorders in morphological and structural of ameloblasts. Results of immunohistochemistry showed that the expression of Beclin1 and LC3 increased while p62 expression decreased in rat ameloblasts drinking 150 mg/L fluoride, and the expression of Cleaved Caspase-3 increased. these changes are more obvious than rats drinking 75 mg/L fluoride-containing water. After administration 3-MA to inhibit autophagy, and they, in turn, decreased the expression of Beclin1 and LC3 and increased the p62 expression. Meanwhile, the expression level of Cleaved Caspase-3 in ameloblast increased significantly. Conclusions There is autophagy in rat ameloblast with chronic fluorosis, the induction of it is enhanced by the high concentration of fluoride and may play a protective role in reducing the level of apoptosis in ameloblasts during the fluorosis.

Objective　 To observe the effects of gallic acid on autophagy of human tongue squamous cell carcinoma SCC15 cell line and investigate their related molecular mechanism. Methods MTT assay was used to detect the effect of different concentrations of gallic acid on SCC15 cell proliferation. Monodansylcadaverine (MDC) staining was used to detect the effect of gallic acid on the autophagosome formation of SCC15 cells. Western blot was applied to detect the effect of gallic acid on the protein expression of LC3Ⅰ, LC3Ⅱ, Beclin1, and p-Akt and p-mTOR in PI3K/Akt/mTOR pathway. Results MTT assay showed that the inhibitory rate of SCC15 cells was significantly increased after 24 and 48 hours in the 90, 120, 150, 300, 600 μmol/L gallic acid group, with a dose-dependent relationship (P < 0.05). MDC staining results revealed that the scattered point fluorescence particles in the cytoplasm and around the nucleus of SCC15 in the 300 μmol/L gallic acid group were significantly increased. Western blot showed that gallic acid increased the ratio of LC3Ⅱ/LC3Ⅰ and the protein expression of Beclin1 after 48 hours (P＜0.05), while it significantly decreased the protein expressions of p-Akt and p-mTOR (P＜0.05). Conclusion Gallic acid under certain concentration can induce autophagy of SCC15, whose mechanism may be related to the down-regulation of the protein expression of p-Akt and p-mTOR through PI3K/Akt/mTOR pathway and the up-regulation of LC3 and Beclin1 protein expression.

Abstract Objective We are going to investigate the relationship between preterm premature rupture of membranes (pPROM) and periodontal diseases by comparing the periodontal conditions and serum levels of Il-6, CRP and PCT in pregnant women with pPROM and those are none preterm rupture of membranes (nPROM). Methods In this study, 40 cases of pPROM and 40 cases of nPROM from the maternity ward of Shengjing hospital affiliated to China medical university were selected. After signing the informed consent, clinical periodontal examination was performed to determine whether the pregnant women had periodontitis to be further divided into four groups. Results The prevalence of periodontitis in pPROM pregnant women was higher than that in nPROM pregnant women (?2=5.115, P=0.024). PD (P=0.001) and SBI (P=0.037) in group A were significantly higher than those in group C. PD of group B was significantly higher than that of group D (P=0.011).There was no statistically significant difference in PLI between groups A and C, B and D, C and D, with P values of 0.292, 0.532 and 0.060, respectively. The levels of IL-6 (P=0.002), CRP (P=0.016) and PCT (P=0.009) in group A were significantly higher than that in group B, and the levels of IL-6 (P=0.009) and CRP (P=0.002) in group C were significantly higher than that in group D. There was no statistically significant difference in PCT levels among other groups except for group A and B (P >0.05). Conclusion pPROM may indicate a higher prevalence of periodontitis. The host's immune response may be one of the key pathways through which PD and pPROM interact, and IL-6 and CRP may be crucial in this process.

Objective To summarize clinical outcomes of immediate loading and nonimmediate loading, judging that whether the outcome of immediate loading implants can be expected, and whether it can satisfy clinical demand and potential influencing factors, giving suggestions to further clinical trials. Methods Our study searched foreign database for relevant articles up to December 2018, and collected clinical parameters of immediate and nonimmediate loading implants including marginal bone loss, marginal bone loss change, implant stability quotient and survival rate of implants, established database to perform Metaanalysis. Results Finally, 32 studies were included in the analysis. As for marginal bone loss, marginal bone loss change, implant stability quotient and survival rate of implants, there was no significant difference between clinical outcomes of immediate loading and nonimmediate loading. Conclusion It is shown that there is no significant difference between immediate loading and nonimmediate loading for implant restoration on patients without systematic diseases, and the outcome of immediate loading implant is expectable.

Objective To evaluate the effect of three different retention methods on the restoration of unilateral maxillary defect. Methods 27 patients with unilateral maxillary defects were divided into three groups according to the different retention methods of prosthesis: 8 cases in the bending clasp group, 10 cases in the casting clasp group, and 9 cases in the attachment combined casting clasp group. One week after the prosthesis was worn in mouth and operated normally, the masticatory efficiency, speech intelligibility and patients' self satisfaction score were measured. The differences of evaluation indexes among the three groups were compared by one-way ANOVA and Tukey HDS test.ResultsThe mean amounts of masticatory efficiency of the three groups were 50.29 ± 5.48, 63.44 ± 4.92 and 69.75 ± 6.18, respectively, with significant differences among the groups (P < 0.05).The mean amounts of speech intelligibility were 60.05 ± 5.31, 82.74 ± 7.12 and 86.40 ± 7.94, respectively, with the worst speech intelligibility in the bending clasp group, which was significantly lower than the other two groups (P < 0.05). In terms of patients' self satisfaction score, the attachment group was the highest, significantly higher than that of the blending clasp group (P < 0.05). The casting clasp group scored significantly higher than that of the bending clasp group in terms of voice clarity, denture stability and chewing function (P < 0.05), but no significant difference between both groups in terms of comfort and aesthetics (P > 0.05).Conclusions The prosthesis with attachment and cast clasp can improve the mastication and speech function of patients with unilateral maxillary defect, and improve the patients' satisfaction and quality of life.If several healthy natural teeth left on the healthy side, the prosthesis with attachment maybe the better method for the unilateral maxillary defect restoration.

Objective　To find the differential expression genes (DEGs) between ameloblastoma and odontogenic keratocyst, analyze their function, and explore the mechanism of ameloblastoma invasion and growth. Methods The gene chip data set GSE38494 was downloaded from GEO database. The LIMMA packets was used to analyze the differential expression genes between ameloblastoma and odontogenic keratocyst. Then the Database for Annotation, Visualization and Integrated Discovery (DIVID) was employed to analyze Gene Oncology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The PPI network of differential expression genes was constructed on Search Tool for the Retrieval of Interacting Genes (STRING) website. The results were visualized by Cytoscape software, and the hub genes were screened by MCODE plug-in. Results 335 differential genes were identified. GO analysis showed that differential genes mainly affected neuronal differentiation, cell adhesion, biological adhesion, cell morphogenesis involved in differentiation, cell fate commitment and other biological processes. Cell component enrichment was mainly involved in extracellular domain, extracellular matrix, extracellular region, proteinaceous extracellular matrix, component and synapse of extracellular matrix structure and so on. The molecular function of enrichment was mainly involved in carbohydrate binding, heparin binding and transcription factor activity. KEGG pathway analysis showed that differential genes were mainly engaged in signaling pathways such as ECM-receptor interaction, axon orientation and pathway in cancer. The 8 hub genes were SPARCL1, SERPINA1, ITIH2, IGFBP5, LAMB1, C3, GOLM1 and FAM20A. Conclusion The DEGs between ameloblastoma and odontogenic keratocyst are screened out by means of bioinformatics. The 8 hub genes are expected to become new markers for differential diagnosis between ameloblastoma and odontogenic keratocyst, and provide new ideas for studies on ameloblastoma.

Objective To compare the antibacterial properties of a toothpaste containing both fluoride and chlorhexidine with a toothpaste only containing fluoride. Methods The antibacterial ring sizes of different toothpastes against Porphyromonas gingivalis (P.gingivalis), Streptococcus sanguis (S.sanguis), Streptococcus mutans (S.mutans), Escherichia coli (E.coli), and Staphylococcus aureus (S. aureus) were measured. A threespecies biofilm model that consists of S.mutans, S.sanguis and P.gingivalis was established on the hydroxyapatites discs (HAs, d=6 mm) in vitro. The biofilms on the surface of HAs were detected by crystal violet staining and LIVE/DEAD bacteria staining to evaluate the antibiofilm properties of different toothpastes. Results Toothpastes with both fluoride and chlorhexidine and toothpaste with fluoride both had a certain antibacterial effect on five kinds of bacteria. The viability of the threespecies biofilms was significantly inhibited by two kinds of toothpastes. The biomass and thickness of the biofilms were significantly reduced by the toothpaste containing both fluoride and chlorhexidine. Conclusion Toothpastes containing both fluoride and chlorhexidine have greater effects on antibacterial properties than a conventional fluoridecontaining toothpaste.

Objective To compare the microleakage and microtensile bond strengths of glass ionomer cement sealant with or without acid etching in primary molars. Methods A total 24 second primary molars in vitro were randomly divided into two groups: the acid etching and the liquid conditioned groups. Both groups were placed in pit and fissure sealant with Ketac Molar Easymix glass ionomer by ART filling finger pressing technique. Then the microleakage and the microtensile strength tests were performed, the microsurface changes of enamel of the samples and the conditions of the section combination and interface of pits and fissures with sealant were observed by scanning electron microscope (SEM). Results The microleakage score in the acid etching group was lower than the liquid conditioned group with significant difference (P<0.05). The microtensile bond strengths of the acid etching and the liquid group were （0.93±0.40）MPa and (0.56±0.22)MPa, respectively, indicating significant difference between the two groups (P<0.05). SEM images showed that enamel surfaces presented topical etching pattern and the enamel and GIC interface revealed the hybridlikely layer in the acid etching sample. The continuous microgap was found between the enamel and GIC interface in the conditioner sample. Conclusion Acid etching produces microporous structure on the surface of enamel, which is conducive to improve GIC sealant penetration and the bonding with enamel structure and reduce microleakage.

Taurodontism with large pulp chambers in which the bifurcation or trifurcation is displaced apically and hence that the chamber has greater apico-occlusal height than in normal teeth and lacks the constriction at the level of cemento-enamel junction (CEJ). The distance from the trifurcation or bifurcation of the root to the CEJ is longer than the occluso-cervical distance. One case of taurodontism in deciduous molar was reported and relevant literatures were reviewed. The possible etiology, diagnostic classification and treatment of taurodontism were discussed.

Bacteria and their by-products are one of the most important causes for pulpal and periapical diseases, and root canal treatment is currently the most effective solution for their treatment. The main reason of the failure of root canal treatment is the occurrence of reinfection within the root canal system, and Enterococcus faecalis (E. faecalis) is one of the major pathogens. The antibacterial effect of endodontic sealers plays an important role in preventing reinfection to the root canal system, which can improve the long-term success rate of root canal treatment. Presently, various of endodontic sealers are available clinically, and the objective of this review was to summarize the antibacterial effects of different endodontic sealers on E. faecalis, which will provide significant evidence for the clinical application of endodontic sealers in root canal treatment.

In the treatment of dental caries, the remineralization of dental hard tissue and the bonding of restorative materials and dental hard tissue in the complex oral environment have been the key issues in the field of dental treatment. The regulation of extracellular matrix proteins and their derivatives or synthetic polymers on the development of tooth hard tissues during the development of natural enamel and dentin. Mussels in the ocean have mussel foot silk protein to provide strong adhesion to rocks. These natural biomimetic biomolecular materials are related to the remineralization of tooth hard tissue and the bonding between restoration materials and tooth hard tissue in the complex oral environment. The purpose of this paper is to summarize the remineralization of these biomimetic biomaterials in the hard tissues of teeth and the bonding effect between the restorative materials and the hard tissues of teeth in recent years.

The type, intervention or non-intervention, and the timing of intervention of ectopic eruption of maxillary first permanent molar have always been the trouble in the clinical process of dentists. In order to help dentists to diagnose the type of ectopic eruption early and accurately, and to formulate the correct treatment plan in time, this article will review the research progress from the aspects of incidence and etiology, typing and reversible rate, complications, treatments, and predictive factors.

Mechanosensitive channel is an ion channel that can sense changes in the cell membrane's mechanical forces and respond quickly. This reaction can convert the mechanical signals felt by the cell membrane into electrical or chemical signals, which affects the body's physiology and biochemistry. Costo and other scientists discovered the Piezo channel protein as a type of mechanically sensitive membrane ion channel that is widely found in animals and plants and eukaryotes in 2010. It contains two proteins in vertebrates, namely Piezo1 (Fam38A) and Piezo2 ( Fam38B). In humans, Piezo1 is mainly expressed in fluid pressure and flowing non-sensory tissues (eg, kidneys, red blood cells), while Piezo2 is mainly expressed in sensory tissues (eg, dorsal root ganglion (DGR) and Merkel cells). This article reviews the research status of Piezo1 mechanically sensitive ion channels and their research in the field of stomatology.

In recent years, with the development of tissue engineering, calcium phospholipid-binding protein VII (Copine VII, CPNE7), as a member of the Copine family, has been found to play more roles in oral tissue regeneration besides its roles in the occurrence and development of cancers. In addition to inducing the difference of odontogenic/non-odontogenic cells into odontoblasts and promoting the differentiation of odontoblasts into dentin, CPNE7 can also promote periodontal tissue regeneration and osteogenesis. In this review, the effects of CPNE7 on oral tissue regeneration and development of neoplastic diseases are presented which will provide a reference for researches in tissue regeneration and diagnosis and treatment of related diseases.

Bone morphogenetic protein heterodimers have received much attention because they have lower dosages and higher osteogenesis-inducing ability than homodimers. This article introduces the related research of BMP heterodimers, including species and structure, mechanism of action, and research on osteoinduction, to compare the functional differences between them and BMP homodimers, and prospect their future.