[Research progress on curcumin improving chronic low-grade inflammation and related diseases].

Chronic low-grade inflammation(CLGI), a relatively new concept without a clear definition, refers to a nonspecific, chronic, continuous, and low-grade inflammation state, and it is closely associated with various chronic diseases, including obesity, inflammatory bowel disease, neurodegenerative diseases, and tumors. Improvement of CLGI can slow down disease progression. Anti-inflammatory treatment is an important strategy for prevention and treatment of CLGI. However, there is currently no definitive drug treatment method. Curcumin is a polyphenolic compound extracted from the rhizome of zingiberaceae, with significant anti-inflammatory activity. Research has shown that curcumin can play an anti-inflammatory role by regulating NF-κB, JAK/STAT, PI3K/Akt, MAPK, NLRP3 inflammasome, Nrf2/ARE, and other inflammation-related pathways. This paper summarized the anti-inflammatory mechanisms, pharmacological effect, and clinical application of curcumin in improving CLGI and other diseases, so as to provide a reference for in-depth research and clinical application of curcumin in improving CLGI.

[Stress analysis of mandibular second premolar with three different restorations].

OBJECTIVE: To investigate the stress intensity and distribution in the dentine of intact endodontically treated mandibular second premolar under three different restorations. METHODS: Four three-dimensional finite element models were constructed by the data of spiral CT: 1) Mandibular second premolar restored directly by full crown: 2) Fill the perforating cavity with resin material and full crown restoration; 3) Cast nickel chromium (NiCr) alloy post core plus full crown restoration; 4) Fiber post and resin core plus full crown restoration. Load was applied on the buccal inclined surface near the top of the buccal cusp and the intensity and distribution of the maximum tensile stress and von Mises stress in the dentine were compared. RESULTS: When the tooth was restored with NiCr alloy post core, an obvious stress concentration area was observed in the dentine next to the top of the post. When the fiber post was used, there was little stress concentration area around the top of the post, and the stress distribution in the dentine was almost the same as the control group. No difference of the intensity and distribution of the stress was found with the control group when no post was used and the perforating cavity was just filled with resin material. CONCLUSION: Compared with cast metal post, fiber post is more suitable for post-core crown restorations. In cases with sufficient coronal tooth substance, post is not absolutely necessary and just filling the perforating cavity with resin material followed by crown restoration can be one of the alternative restorations.