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Objective @# To investigate the effect of pathogenic bacterium-Porphyromonas gingivalis (P.g) on the proliferation and inflammatory factor expression of human colorectal cancer Caco-2 cells, to determine whether the Janus kinase 2-signal transducers and activators of transcription 3 (JAK2-STAT3) pathway is involved in the regulation of Caco-2 cell proliferation by P.g and to provide an experimental basis for further exploring the relationship between P.g and colorectal cancer. @*Methods @# Caco-2 cells were cultured in vitro, and P.g at different multiplicities of infection (MOIs) (0, 1, 10, 25) was selected to stimulate for 12, 24 and 48 h. The effect of P.g on the proliferation of Caco-2 cells was detected by CCK8. The stimulation time was set as 12, 24 and 48 h. MOI=0 was the control group, and MOI=1, 10 and 25 comprised the experimental group. qRT-PCR and Western blot were used to detect the changes in interleukin-6 (IL-6), interleukin-10(IL-10), JAK2 and STAT3 gene and protein (phosphorylated protein) levels in each group. @*Results @# After P.g infection of Caco-2 cells, P.g had a sustained stimulatory effect on the cells for 12, 24 and 48 h at MOI=1 and MOI=10 compared with the control group. Compared with that in the control group, the expression of pro-inflammatory factor IL-6 and related proliferative pathway protein JAK2 and STAT3 in Caco-2 cells with P.g infection increased in a concentration- and time-dependent manner (P<0.05). Additionally, the expression of IL-10, an anti-inflammatory factor, in Caco-2 cells infected with P.g decreased (P<0.05). After the addition of the JAK2 inhibitor AZ960, the proliferation of Caco-2 cells infected with P.g decreased, and the mRNA expression of STAT3 and JAK2 and the protein expression of p-STAT3 and p-JAK2 decreased (P<0.05). @*Conclusion @#P.g can promote the proliferation of the colorectal cancer cell line Caco-2, and the effect of P.g on Caco-2 cells may promote cell proliferation through the JAK2-STAT3 pathway while promoting the expression of the proinflammatory factor IL-6 and inhibiting the expression of the anti-inflammatory factor IL-10, creating an inflammatory environment conducive to cell proliferation, which may be the mechanism by which P.g affects the proliferation of Caco-2 cells.
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@#The endocrown, a modified overlay or crown, is considered to have the advantages of adhesive retention and mechanical retention. Marginal adaptation and mechanical strength are common criteria for evaluating endocrowns. This review studied these aspects of endocrowns to guide further clinical application. Results from previous academic studies indicate that endocrowns made of different materials, such as glass-based ceramics, zirconia-based ceramics and resin-based ceramics, exhibit clinically acceptable marginal adaptation. Zirconia is a common dental material, but when used in endocrowns, it tends to present a risk of irreparable tooth root fractures. Compared with products manufactured with zirconia, endocrowns manufactured with resin-based ceramics and glass-based ceramics, such as lithium disilicate ceramics, do not tend to cause irreparable results, such as tooth root fracture, but their mechanical strengths are not as good as those of zirconia. At the same time, the tooth prepration design such as the types of endocrowns, the pulp chamber extension depth and angles, the endocrown thickness can influence the mechanical strength of endocrowns as well. Compared with traditional zirconia, self-glazed zirconia, a new type of material used to restore defective teeth, has the similar elasticity modulus（210 GPa）and better aesthetic advantages, and is suitable for short crown patients with insufficient occlusal space. Further study is warranted to improve the performance of endocrowns made from ceramic materials to prevent root fracture.
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@#In recent years, due to precise control of the amorphous mineral precursor in the demineralization of dentine collagen fibers in orderly deposition, forming apatite crystals similar to the natural mineralized dentin, the bottom-up remineralization approach which does not depend on the existence of seed crystallites, dentin biomimetic mineralization techniques gradually become a hotspot in the research field of restoration of demineralized dentin caused by dental caries. This paper reviews the changing concepts and practices of the remineralization of demineralized dentin, emphasizing biomimetic remineralization studies. The results of the literature review show that the traditional dentin remineralization method is usually a disordered mixture of demineralized dentin and minerals, so mineralized dentin is not comparable to natural mineralized dentin in terms of the morphological characteristics and mechanical properties. With its gradual increase in recent years, dentine biomimetic mineralization technology perfectly resembles the minerals in the dentin overlapping sequence arranged with the dentine collagen fiber structure characteristics, leading to greatly improved microstructural, physical and chemical properties. As a result, dentine biomimetic mineralization technology is expected to achieve new breakthroughs in the fields of resin-dentin bonding mixing layers and the decay of dentin. At present, the technical obstacles that need to be overcome in the clinical application of the biomimetic remineralization of dentin are how to continuously supplement all the active ingredients needed for mineralization in the process of remineralization and how to keep the mechanical properties of the parent material unchanged while slowly releasing all ingredients. Researchers have successively proposed three-step transportation of the biomimetic remineralization of raw materials, as well as the preparation of mineralization precursors stabilized by polymers in advance and the reuse of mesoporous silicon nanomaterials for the transportation of the mineralized ingredient system. The concept described above provides the preliminary in vitro experimental basis for the transformation of the biomimetic remineralization strategy of dentin in clinical applications.