Jingxian Zhu

Periodontitis is a chronic inflammatory disease characterized by progressive alveolar bone destruction and represents a major cause of tooth loss. It has also been associated with systemic inflammatory conditions such as diabetes. Circadian rhythms, governed by clock genes, are essential for maintaining physiological homeostasis across various tissues. Circadian rhythm disruption, such as that caused by night shift work, has been associated with severe periodontitis; however, the underlying mechanisms remain incompletely understood. Period 2 (Per2), a core peripheral clock gene expressed in periodontal tissues, was investigated for its role in inflammatory bone loss under circadian disruption. In a murine ligature model, circadian disruption exacerbated alveolar bone loss, while Per2 deficiency amplified inflammatory responses. Consistently, PER2 knockdown in TNF-α-stimulated human periodontal ligament cells (hPDLCs) led to increased expression of pro-inflammatory cytokines IL-1β and IL-6. Interestingly, Per2 knockout also led to increased basal bone mass compared with WT mice. Mechanistically, we found miR-21, a PER2-regulated microRNA, displayed rhythmic expression in hPDLCs and was downregulated following PER2 knockdown. Further investigation demonstrated that the PER2/miR-21 axis negatively regulates osteogenic differentiation under non-inflammatory conditions via TGF-β/SMAD signaling, while under inflammatory conditions, its downregulation failed to suppress PDCD4/NF-κB signaling, resulting in elevated pro-inflammatory cytokine secretion. Finally, local delivery of miR-21 agomir significantly promoted bone recovery after ligature removal. Together, these findings identify PER2 as a key circadian regulator of inflammation-associated bone homeostasis and highlight miR-21 as a potential therapeutic target for bone regeneration in periodontitis.

Tooth developmental anomalies are a group of disorders caused by unfavorable factors affecting the tooth development process, resulting in abnormalities in tooth number, structure, and morphology. These anomalies typically manifest during childhood, impairing dental function, maxillofacial development, and facial aesthetics, while also potentially impacting overall physical and mental health. The complex etiology and diverse clinical phenotypes of these anomalies pose significant challenges for prevention, early diagnosis, and treatment. As they usually emerge early in life, long-term management and multidisciplinary collaboration in dental care are essential. However, there is currently a lack of systematic clinical guidelines for the diagnosis and treatment of these conditions, adding to the difficulties in clinical practice. In response to this need, this expert consensus summarizes the classifications, etiology, typical clinical manifestations, and diagnostic criteria of tooth developmental anomalies based on current clinical evidence. It also provides prevention strategies and stage-specific clinical management recommendations to guide clinicians in diagnosis and treatment, promoting early intervention and standardized care for these anomalies.

Lymph node (LN) metastasis is a prevalent cause of recurrence in oral squamous cell carcinoma (OSCC). However, accurately identifying metastatic LNs (LNs+) remains challenging. This prospective clinical study aims to test the effectiveness of our convolutional neural network (CNN) model for identifying OSCC cervical LN+ in contrast-enhanced computed tomography (CECT) in clinical practice. A CNN model was developed and trained using a dataset of 8,380 CECT images from previous OSCC patients. It was then prospectively validated on 17,777 preoperative CECT images from 354 OSCC patients between October 17, 2023, and August 31, 2024. The model’s predicted LN results were provided to the surgical team without influencing surgical or treatment plans. During surgery, the predicted LN+ were identified and sent for separate pathological examination. The accuracy of the model’s predictions was compared with those of human experts and verified against pathology reports. The capacity of the model to assist radiologists in LN+ diagnosis was also assessed. The CNN model was trained over 40 epochs and successfully validated after each. Compared with human experts (2 radiologists, 2 surgeons, and 2 students), the CNN model achieved higher sensitivity (81.89% vs. 81.48%, 46.91%, 50.62%), specificity (99.31% vs. 99.15%, 98.36%, 96.27%), LN+ accuracy (76.19% vs. 75.43%, P = 0.854; 40.64%, P < 0.001; 37.44%, P < 0.001), and clinical accuracy (86.16% vs. 83%, 61%, 56%). With the model’s assistance, the radiologists surpassed both the previous predictive results without the model’s support and the model’s performance alone. The CNN model demonstrated an accuracy comparable to that of radiologists in identifying, locating, and predicting cervical LN+ in OSCC patients. Furthermore, the model has the potential to assist radiologists in making more accurate diagnoses.

Objectives: To assess the long‐term clinical outcomes and patient satisfaction with narrow‐diameter implants (NDIs) in the posterior jaws and to identify the risk indicators for NDI failure.Materials and Methods: This retrospective study reviewed 479 patients with 666 NDIs (diameter ≤ 3.5 mm) ‐supported fixed prostheses in posterior jaws, with a minimum 10‐year follow‐up. Implant survival, success, complications, demographics, and implantation characteristics were collected. Risk indicators for posterior NDI failure were analyzed using multilevel Cox regression analyses with mixed effects. Patient satisfaction and oral health impact profile (OHIP) were surveyed in a random 10% sample.Results: Over a mean follow‐up of 14.0 ± 3.6 years, implant survival was 95.9% at the implant level and 94.6% at the patient level. Success rates were 93.5% at the implant level and 91.6% at the patient level. Multilevel Cox regression analysis identified an implant length of 10 mm or less (p = 0.001) and the use of single crowns (p = 0.005) as significant risk indicators for posterior NDI failure. Patients showed high satisfaction (4.54/5) with posterior NDIs, and the mean OHIP score of 1.15 reflected an acceptable level of oral health.Conclusion: NDIs in the posterior jaws demonstrated robust long‐term success and high patient satisfaction. An implant length of 10 mm or less and the use of single crowns are potential risk indicators for posterior NDI failure.Trial Registration: Chinese Clinical Trial Registry: ChiCTR2200062337 on 2022/08/02

The jawbone periosteum, the easily accessible tissue responding to bone repair, has been overlooked in the recent development of cell therapy for jawbone defect reconstruction. Therefore, this study aimed to elucidate the in vitro and in vivo biological characteristics of jawbone periosteum‐derived cells (jb‐PDCs). For this purpose, we harvested the jb‐PDCs from 8‐week‐old C57BL/6 mice. The in vitro cultured jb‐PDCs (passages 1 and 3) contained skeletal stem/progenitor cells and exhibited clonogenicity and tri‐lineage differentiation capacity. When implanted in vivo, the jb‐PDCs (passage 3) showed evident ectopic bone formation after 4‐week subcutaneous implantation, and active contribution to repair the critical‐size jawbone defects in mice. Molecular profiling suggested that R‐spondin 3 was strongly associated with the superior in vitro and in vivo osteogenic potentials of jb‐PDCs. Overall, our study highlights the significance of comprehending the biological characteristics of the jawbone periosteum, which could pave the way for innovative cell‐based therapies for the reconstruction of jawbone defects.

Fibroblast growth factor 23 (FGF23) plays a crucial role in managing renal phosphate and the synthesis of 1,25(OH)2-vitamin D3, which is essential for bone homeostasis. Developing robust in vitro systems to study FGF23-regulating mechanisms is crucial for advancing our knowledge and identifying potential therapeutic targets. The traditional in vitro 2D culture system results in relatively low expression of FGF23, complicating further exploration of its regulatory mechanisms and potential therapeutic targets. Herein, we reported a high-throughput approach to generate preosteoblastic cell spheroids with enhanced FGF23 production. For this purpose, murine preosteoblast cell line (MC3T3-E1) was cultured in our previously reported nonadherent microwells (200 µm in diameter, 148 µm in depth, and 100 µm space in between) and self-assembled into spheroids with a diameter of 92.3 ± 15.0 µm after 24 h. Compared with monolayer culture, the MC3T3-E1 spheroids showed a significant upregulation of FGF23 in both gene and protein levels after 24 h of serum-free induction. RNA sequencing and western blotting analysis further suggested that the enhanced FGF23 production in MC3T3-E1 spheroids was attributed to the activation of the parathyroid hormone (PTH)/PTH1R signaling pathway. Impressively, inhibition of PTH signaling through small molecular inhibitors or short hairpin RNA targeting PTH1R effectively reduced FGF23 production. In summary, the current study revealed the efficacy of the high-throughput formation of preosteoblast cell spheroid in stimulating FGF23 expression for mechanistic studies. Importantly, our findings highlight the potential of the current 3D spheroid system for target identification and drug discovery.

Recapitulation of the natural healing process is receiving increasing recognition as a strategy to induce robust tissue regeneration. Endochondral ossification has been recognized as an essential reparative approach in natural jawbone defect healing. However, such an approach has been overlooked in the recent development of cell-based therapeutics for jawbone repair. Therefore, this study aimed to explore a bioinspired stem cell–based strategy for jawbone repair by mimicking the mesenchymal condensation of progenitor cells during the early endochondral ossification process. For this purpose, passage 3 of jawbone periosteum-derived cells (jb-PDCs) was cultured in our previously reported nonadherent microwells (200 µm in diameter, 148 µm in depth, and 100 µm space in between) and self-assembled into spheroids with a diameter of 96.4 ± 5.8 µm after 48 h. Compared to monolayer culture, the jb-PDC spheroids showed a significant reduction of stemness marker expression evidenced by flow cytometry. Furthermore, a significant upregulation of chondrogenic transcription factor SOX9 in both gene and protein levels was observed in the jb-PDC spheroids after 48 h of chondrogenic induction. RNA sequencing and Western blotting analysis further suggested that the enhanced SOX9-mediated chondrogenic differentiation in jb-PDC spheroids was attributed to the activation of the p38 MAPK pathway. Impressively, inhibition of p38 kinase activity significantly attenuated chondrogenic differentiation jb-PDC spheroids, evidenced by a significant decline of SOX9 in both gene and protein levels. Strikingly, the jb-PDC spheroids implanted in 6- to 8-wk-old male C57BL/6 mice with critical-size jawbone defects (1.8 mm in diameter) showed an evident contribution to cartilaginous callus formation after 1 wk, evidenced by histological analysis. Furthermore, micro–computed tomography analysis showed that the jb-PDC spheroids significantly accelerated bone healing after 2 wk in the absence of exogenous growth factors. In sum, the presented findings represent the successful development of cell-based therapeutics to reengineer the endochondral bone repair process and illustrate the potential application to improve bone repair and regeneration in the craniofacial skeleton.

Objectives: To compare implant placement accuracy and patient‐centered results between the dynamic computer‐assisted implant surgeries (d‐CAISs) using marker‐based and marker‐free registration methods.Materials and Methods: A double‐armed, single‐blinded randomized controlled trial was conducted, in which 34 patients requiring single implant placement at the esthetic zone were randomly assigned to the marker‐based (n = 17) or marker‐free (n = 17) groups. The marker‐based registration was performed using a splint containing radiopaque markers, while the marker‐free registration used natural teeth. The primary outcome assessed implant positioning accuracy via angular and linear deviations between preoperative and postoperative implant positions in CBCT. Patients were also surveyed about the intraoperative experience and oral health impact profile (OHIP).Results: The global linear deviations at the implant platform (0.82 ± 0.28 and 0.85 ± 0.41 mm) and apex (1.28 ± 0.34 and 0.85 (IQR: 0.64–1.50) mm) for the marker‐based and marker‐free groups respectively showed no significant difference. However, the angular deviation of the marker‐free group (2.77 ± 0.92) was significantly lower than the marker‐based group (4.28 ± 1.58). There was no significant difference in the mean postoperative OHIP scores between the two groups (p = .758), with scores of 2.74 ± 1.21 for marker‐based and 2.93 ± 2.18 for marker‐free groups, indicating mild oral health‐related impairment in both. Notably, patients in the marker‐free group showed significantly higher satisfaction (p = .031) with the treatment procedures.Conclusions: D‐CAIS with a marker‐free registration method for single implantation in the anterior maxilla has advantages in improving implant placement accuracy and patients' satisfaction, without generating a significant increase in clinical time and expenses.

Bone marrow stromal cells (BMSCs) and periosteum-derived cells (PDCs) represent promising skeletal stem cell sources to treat critical-size bone defects. However, the large number of preclinical tests with a variety of in vivo data complicates the selection of cells for further clinical translation. This systematic review aims to analyze the in vivo bone-forming efficacy of BMSCs- and PDCs-based approaches in all published preclinical experiments until November 2020. For this purpose, four databases (PubMed, Embase, Cochrane Central Register of Controlled Trial, and Web of Science) were searched for eligible literature, which yielded a total of 94 full-text articles for systematic review. This review generated an evidence-based list of BMSC- or PDC-based approaches, which have been evaluated for bone formation in different animal models. Among them, 74 studies were included for pairwise and network meta-analysis. The results revealed that both PDC and BMSC had beneficial bone-forming efficacy compared to bare scaffold. In addition, BMSC- and PDC-based approaches had no significant difference regarding in vivo bone-forming efficacy. However, BMSC-based approach had a higher probability to be ranked better than PDC-based approach. Furthermore, the review discusses (i) the possible risk of bias of the in vivo evaluation of cell-based approaches, (ii) the difficulty in replication of such experiments due to frequent poor reporting of the methods and results, and (iii) the clinical relevance of the currently utilized BMSC- and PDC-based approaches. Systematic review registration: The study was prospectively registered in PROSPERO, Registration No. CRD42021270922.

Aim: To explore the expression profile and prognostic value of MCTS1 in head and neck squamous cell carcinoma (HNSC). Materials & methods: This study used the data from TCGA to HNSC database, GEO database and the data and specimens collected from the patients in our hospital to conduct a comprehensive bioinformatic analysis of MCTS1 in HNSC. Results: MCTS1 was significantly upregulated. MCTS1 mRNA expression level is a potential prognostic biomarker for overall survival and recurrence-free survival. We revealed the potential interactions of MCTS1 with other molecules and potential relationship with ubiquitination, translation initiation and mRNA splicing in HNSC. Conclusion: MCTS1 was significantly upregulated in primary HNSC. The correlation of MCTS1 with poor prognosis suggested its potential as a prognostic marker for HNSC patients.