BACKGROUND:Platelet-rich fibrin(PRF)has many advantages,such as simple preparation,low production cost,and high safety,and has been widely used in the study of bone defect repair in oral and maxillofacial surgery,but there are problems such as too fast degradation rate and short release time of growth factors. OBJECTIVE:PRF was loaded into gelatin methacryloyl(GelMA)hydrogel and its osteogenic properties were analyzed by in vivo and in vitro experiments. METHODS:(1)New Zealand white rabbit venous blood was extracted to prepare PRF.GelMA hydrogels containing 0,0.05,0.075,and 0.1 g PRF were prepared,respectively,and were recorded as GelMA,GelMA/PRF-0.05,GelMA/PRF-0.075,and GelMA/PRF-0.1,respectively,to characterize the micromorphology and in vitro slow-release properties of the hydrogels.(2)Four kinds of hydrogels were co-cultured with MC3T3-E1 cells,respectively,and the cell proliferation activity was detected with the single cultured cells as the control.After osteogenic induction,alkaline phosphatase activity,mineralization ability,mRNA and protein expression levels of osteogenic genes(osteocalcin,osteopontin,RUNX2),ERK1/2-p38 MAPK pathway protein mRNA and protein expression levels were detected.(3)Fifteen New Zealand white rabbits were taken.Four full-layer bone defects of 8 mm diameter were prepared in the skull of each rabbit,one of which was implanted without any material(blank control group),and the other three were implanted with GelMA hydrogel,PRF,and GelMA/PRF-0.1 hydrogel,respectively.The bone defect was detected by Micro-CT and bone morphology was observed at 4,8,and 12 weeks after operation. RESULTS AND CONCLUSION:(1)Scanning electron microscopy observed that all the hydrogels of the four groups had honeycomb pore structure,and the pore size of the hydrogels decreased slightly with the increase of PRF content,but there was no significant difference between the groups.The three groups of GelMA/PRF hydrogel could release transforming growth factor β1 and insulin-like growth factor 1 at a certain rate,and the cumulative release of transforming growth factor β1 and insulin-like growth factor 1 increased significantly with the extension of time.(2)CCK-8 assay and live/dead staining showed that GelMA/PRF hydrogel could promote the proliferation of MC3T3-E1 cells.The results of alkaline phosphatase staining,alizarin red staining,and osteogenic gene detection showed that GelMA/PRF hydrogel could promote the osteogenic differentiation of MC3T3-E1 cells,and inhibit the expression of ERK1/2-p38 MAPK pathway protein,and showed a PRF content dependence.(3)Micro-CT scan showed that the bone mineral density and bone volume fraction in the bone defect of GelMA/PRF-0.1 hydrogel group were higher than those in the other three groups(P<0.05).Hematoxylin-eosin staining showed that compared with the other three groups,GelMA/PRF-0.1 hydrogel group had faster and more mature new bone formation at the bone defect.(4)These findings indicate that GelMA/PRF hydrogel has good osteogenic activity both in vivo and in vitro,which may be related to inhibiting the expression of ERK1/2-p38 MAPK pathway protein.

In recent decades, the prevalence of hyperuricemia and gout has increased dramatically due to lifestyle changes. The drugs currently recommended for hyperuricemia are associated with adverse reactions that limit their clinical use. In this study, we report that berberine (BBR) is an effective drug candidate for the treatment of hyperuricemia, with its mechanism potentially involving the modulation of gut microbiota and its metabolite, succinic acid. BBR has demonstrated good therapeutic effects in both acute and chronic animal models of hyperuricemia. In a clinical trial, oral administration of BBR for 6 months reduced blood uric acid levels in 22 participants by modulating the gut microbiota, which led to an increase in the abundance of Bacteroides and a decrease in Clostridium sensu stricto_1. Furthermore, Bacteroides fragilis was transplanted into ICR mice, and the results showed that Bacteroides fragilis exerted a therapeutic effect on uric acid similar to that of BBR. Notably, succinic acid, a metabolite of Bacteroides, significantly reduced uric acid levels. Subsequent cell and animal experiments revealed that the intestinal metabolite, succinic acid, regulated the upstream uric acid synthesis pathway in the liver by inhibiting adenosine monophosphate deaminase 2 (AMPD2), an enzyme responsible for converting adenosine monophosphate (AMP) to inosine monophosphate (IMP). This inhibition resulted in a decrease in IMP levels and an increase in phosphate levels. The reduction in IMP led to a decreased downstream production of hypoxanthine, xanthine, and uric acid. BBR also demonstrated excellent renoprotective effects, improving nephropathy associated with hyperuricemia. In summary, BBR has the potential to be an effective treatment for hyperuricemia through the gut-liver axis.

Apical microsurgery is accurate and minimally invasive, produces few complications, and has a success rate of more than 90%. However, due to the lack of awareness and understanding of apical microsurgery by dental general practitioners and even endodontists, many clinical problems remain to be overcome. The consensus has gathered well-known domestic experts to hold a series of special discussions and reached the consensus. This document specifies the indications, contraindications, preoperative preparations, operational procedures, complication prevention measures, and efficacy evaluation of apical microsurgery and is applicable to dentists who perform apical microsurgery after systematic training.
Microsurgery/standards* ; Humans ; Apicoectomy ; Contraindications, Procedure ; Tooth Apex/diagnostic imaging* ; Postoperative Complications/prevention & control* ; Consensus ; Treatment Outcome

Pulpotomy, which belongs to vital pulp therapy, has become a strategy for managing pulpitis in recent decades. This minimally invasive treatment reflects the recognition of preserving healthy dental pulp and optimizing long-term patient-centered outcomes. Pulpotomy is categorized into partial pulpotomy (PP), the removal of a partial segment of the coronal pulp tissue, and full pulpotomy (FP), the removal of whole coronal pulp, which is followed by applying the biomaterials onto the remaining pulp tissue and ultimately restoring the tooth. Procedural decisions for the amount of pulp tissue removal or retention depend on the diagnostic of pulp vitality, the overall treatment plan, the patient's general health status, and pulp inflammation reassessment during operation. This statement represents the consensus of an expert committee convened by the Society of Cariology and Endodontics, Chinese Stomatological Association. It addresses the current evidence to support the application of pulpotomy as a potential alternative to root canal treatment (RCT) on mature permanent teeth with pulpitis from a biological basis, the development of capping biomaterial, and the diagnostic considerations to evidence-based medicine. This expert statement intends to provide a clinical protocol of pulpotomy, which facilitates practitioners in choosing the optimal procedure and increasing their confidence in this rapidly evolving field.
Humans ; Calcium Compounds/therapeutic use* ; Consensus ; Dental Pulp ; Dentition, Permanent ; Oxides/therapeutic use* ; Pulpitis/therapy* ; Pulpotomy/standards*

Intentional tooth replantation (ITR) is an advanced treatment modality and the procedure of last resort for preserving teeth with inaccessible endodontic or resorptive lesions. ITR is defined as the deliberate extraction of a tooth; evaluation of the root surface, endodontic manipulation, and repair; and placement of the tooth back into its original socket. Case reports, case series, cohort studies, and randomized controlled trials have demonstrated the efficacy of ITR in the retention of natural teeth that are untreatable or difficult to manage with root canal treatment or endodontic microsurgery. However, variations in clinical protocols for ITR exist due to the empirical nature of the original protocols and rapid advancements in the field of oral biology and dental materials. This heterogeneity in protocols may cause confusion among dental practitioners; therefore, guidelines and considerations for ITR should be explicated. This expert consensus discusses the biological foundation of ITR, the available clinical protocols and current status of ITR in treating teeth with refractory apical periodontitis or anatomical aberration, and the main complications of this treatment, aiming to refine the clinical management of ITR in accordance with the progress of basic research and clinical studies; the findings suggest that ITR may become a more consistent evidence-based option in dental treatment.
Humans ; Tooth Replantation/methods* ; Consensus ; Periapical Periodontitis/surgery*

Pulpitis is a common infective oral disease in clinical situations. The regulatory mechanisms of immune defense in pulpitis are still being investigated. Osteomodulin (OMD) is a small leucine-rich proteoglycan family member distributed in bones and teeth. It is a bioactive protein that promotes osteogenesis and suppresses the apoptosis of human dental pulp stem cells (hDPSCs). In this study, the role of OMD in pulpitis and the OMD-induced regulatory mechanism were investigated. The OMD expression in normal and inflamed human pulp tissues was detected via immunofluorescence staining. Intriguingly, the OMD expression decreased in the inflammatory infiltration area of pulpitis specimens. The cellular experiments demonstrated that recombined human OMD could resist the detrimental effects of lipopolysaccharide (LPS)-induced inflammation. A conditional Omd knockout mouse model with pulpal inflammation was established. LPS-induced inflammatory impairment significantly increased in conditional Omd knockout mice, whereas OMD administration exhibited a protective effect against pulpitis. Mechanistically, the transcriptome alterations of OMD overexpression showed significant enrichment in the nuclear factor-κB (NF-κB) signaling pathway. Interleukin-1 receptor 1 (IL1R1), a vital membrane receptor activating the NF-κB pathway, was significantly downregulated in OMD-overexpressing hDPSCs. Additionally, the interaction between OMD and IL1R1 was verified using co-immunoprecipitation and molecular docking. In vivo, excessive pulpal inflammation in Omd-deficient mice was rescued using an IL1R antagonist. Overall, OMD played a protective role in the inflammatory response via the IL1R1/NF-κB signaling pathway. OMD may optimize the immunomodulatory functions of hDPSCs and can be used for regenerative endodontics.
Pulpitis/metabolism* ; NF-kappa B/metabolism* ; Animals ; Signal Transduction ; Humans ; Mice ; Mice, Knockout ; Dental Pulp/metabolism* ; Disease Models, Animal ; Lipopolysaccharides

Instrument separation is a critical complication during root canal therapy, impacting treatment success and long-term tooth preservation. The etiology of instrument separation is multifactorial, involving the intricate anatomy of the root canal system, instrument-related factors, and instrumentation techniques. Instrument separation can hinder thorough cleaning, shaping, and obturation of the root canal, posing challenges to successful treatment outcomes. Although retrieval of separated instrument is often feasible, it carries risks including perforation, excessive removal of tooth structure and root fractures. Effective management of separated instruments requires a comprehensive understanding of the contributing factors, meticulous preoperative assessment, and precise evaluation of the retrieval difficulty. The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes. The current manuscript provides a framework for understanding the causes, risk factors, and clinical management principles of instrument separation. By integrating effective strategies, endodontists can enhance decision-making, improve endodontic treatment success and ensure the preservation of natural dentition.
Humans ; Root Canal Therapy/adverse effects* ; Consensus ; Root Canal Preparation/adverse effects*

ObjectiveTo quantitatively investigate the changes in the total volume and contour density of hepatic oval cells （HOC） in hepatic lobules of rats with carbon tetrachloride （CCl₄）-induced hepatic fibrosis. MethodsA total of 11 healthy male Sprague-Dawley rats were randomly divided into control group with 5 rats and hepatic fibrosis group with 6 rats， and CCl₄ and olive oil suspension were injected subcutaneously twice a week， 3 mL/kg each time. After five weeks of hepatic fibrosis modeling， five liver tissue blocks with a size of about 1 mm³ were randomly selected from the liver of each rat to prepare one Epon812 epoxy resin-embedded ultrathin section， and the stereological method and transmission electron microscopy were used for the quantitative analysis of the total volume and contour density of HOC in the hepatic lobules of rats. In addition， four liver tissue blocks with a thickness of 2 mm were randomly selected from the remaining liver of each rat to prepare two paraffin-embedded Masson staining sections， and the degree of liver fibrosis in each rat was qualitatively evaluated according to the Metavir staging criteria for liver fibrosis. The independent-samples t test was used for comparison of continuous data between groups. ResultsThe quantitative stereological analysis showed that the total volume of HOC in hepatic lobules was 15.40±7.63 mm³ in the control group and 146.80±114.00 mm³ in the liver fibrosis group， and compared with the control group， the total volume of HOC in hepatic lobules of rats in the liver fibrosis group was significantly increased by 8.53 times （t=-2.551， P=0.031）； the contour density of HOC in hepatic lobules was 56.20±40.40 in the control group and 566.50±317.00 in the liver fibrosis group， and compared with the control group， the contour density of HOC in hepatic lobules of rats in the liver fibrosis group was significantly increased by 9.08 times （t=-3.539， P=0.006）. Qualitative observation showed that liver fibrosis stage of rats reached stage Ⅱ-Ⅲ according to the Metavir scoring criteria， and massive proliferation of HOC was observed around the proliferation site of hepatic stellate cells in the perisinusoidal space of rats. ConclusionCCl₄ induces significant proliferation of HOC in hepatic lobules of rats with liver fibrosis.

Objective:To evaluate the guiding value of ultrasound-guided selective nerve root block in the surgical treatment of multilevel lumbar degeneration.Methods:Retrospective case-control study was used. Clinical data of 47 patients with multi-level lumbar degeneration who underwent decompression surgery in Honghui Hospital, Xi′an Jiaotong University from January 2019 to December 2021 were retrospectively analyzed. They were divided into nerve root block group ( n=22)and non-nerve root block group( n=25) according to whether ultrasound-guided selective nerve root block was performed before decompression surgery. The operation time, intraoperative blood loss, number of decompression laminae, postoperative drainage volume and length of stay of the two groups were recorded and compared. The visual analogue scale of low back pain, the visual analogue scale (VAS) of leg pain, the Japanese orthopaedic association (JOA) score and Oswestry disability index (ODI) score were all compared before surgery and during follow-up between the two groups. Measurement data with normal distribution were represented as mean±standard deviation( ± s), and the comparison between groups was conducted using the paired t-test. Chi-square test was used for counting data. Results:All 47 patients successfully completed the operation without any serious complications such as neurovascular injury. All patients were followed up for (27.6±7.5)months. In the nerve root block group, the operation time, intraoperative blood loss, number of decompression laminae, postoperative drainage volume and hospital stay were (90.5±12.6) min, (110.5±15.8) mL, 1.2±0.8, (85.6±15.8) mL, (6.2±2.8) d, respectively. In the non-root block group, they were (190.6±25.5) min, (450.5±24.8) mL, 3.8±1.6, (210.5±16.8) mL, (9.5±2.2) d, respectively. The above indexes in the nerve root closure group were less than those in the non-root closure group, and the difference was significant between the two groups ( P< 0.05). The scores of VAS of low back pain and leg pain, JOA and ODI in both groups were significantly improved after surgery and during the follow-up period when compared with those of pre-operation ( P< 0.05). The VAS scores of low back pain on the 3rd day, 6 months after operation and at the last follow-up in the nerve block group were 3.2±1.4, 1.4±0.8, 0.5±0.2, the JOA scores were 15.8±4.3, 21.3±5.6, 25.6±1.4, and the ODI scores were 50.6±10.3, 22.8±7.8, 16.8±4.2, respectively. The VAS scores of low back pain on the 3rd day, 6 months after operation and at the last follow-up in the non-nerve block group were 5.1±1.8, 3.4±1.2, 1.8±0.5, the JOA scores were 14.1±4.8, 20.5±3.2, 24.2±1.8, and the ODI scores were 60.5±9.8, 31.6±8.2 and 21.3±5.5, respectively. The difference between the two groups was statistically significant ( P<0.05). However, there was no statistical difference in the VAS scores of leg pain between the two groups after surgery and during follow-up ( P>0.05). At the last follow-up, the internal fixation position of the two groups was good, no loosening and displacement, and bone graft fusion was good. Conclusion:For patients with multi-level lumbar degeneration, ultrasound-guided selective nerve root block before surgery can identify the responsible segment, and selective decompression and fusion based on this can effectively reduce surgical trauma, while improving patients′ back and leg pain and physical function, which has important surgical guidance value.