Objective:?This study aims to identify key immune cells and differentially expressed genes (DEGs) associated with oxidative stress (OS) in periodontitis by integrating bulk RNA sequencing (Bulk RNA-seq), single-cell RNA sequencing (scRNA-seq), and machine learning algorithms. Methods:?Periodontitis-related gene expression data were collected from the GEO database, to investigate the heterogeneity of OS across various cellular tiers following PD and treatment. Then, OS activity of different immune cell subgroups were evaluated using AUCELL, UCELL, SINGSCORE, and ADDMODULESCORE algorithms to identify key immune cells with high OS activity in periodontitis. Furthermore, machine learning models such as Random Forest, Least Absolute Shrinkage and Selection Operator regression, and Artificial Neural Network were employed to select the best feature genes and construct a risk prediction model. Results: Results from scRNA-seq dataset indicated that OS activity exhibited cellular heterogeneity following PD, with particularly heightened activity observed in monocytes. Next, 3 800 DEGs were identified, of which 111 were OS-related DEGs (OS-DEGs). Machine learning algorithms identified four key OS genes (NFE2L2, KDR, CXCL1, CYBB), which showed significant expression changes in periodontitis patients (P＜0.05) and were highly associated with periodontitis risk. Conclusions: This study unveils the cellular heterogeneity of OS activity and systematically identifies key oxidative stress genes in periodontitis. NFE2L2 and CYBB may exacerbate OS activity by regulating monocyte migration and infiltration, penetrating the periodontal barrier.

Objective: To investigate the changes in stemness characteristics of human periodontal ligament stem cells (hPDLSCs) under hypoxia environment and their effects on osteogenic differentiation in vitro and in vivo. Methods: hPDLSCs were cultured under normoxia and hypoxia environment, and their proliferative ability was studied by CCK-8 and colony forming unit experiments. The senescence was detected by β-galactosidase staining. The expression of stemnessrelated genes sex determining region of Y-box protein 2 (SOX2), octamer binding transcription factor 4 (OCT4) and NANOG was studied by qRT-PCR and Western blot experiments. The supernatant of hPDLSCs under two culture environments was collected and used as the conditioned medium to configure the osteogenic induction medium, then osteogenic induction of hPDLSCs was performed under normoxia. The alkaline phosphatase (ALP) staining, alizarin red staining and the expression of osteogenicrelated genes collagen type Ⅰ(COL-1), osteopontin (OPN), osteocalcin (OCN) and runt related transcription factor 2 (RUNX2) detected by qRT-PCR assay were used to study the ability of hPDLSCs to promote osteogenic differentiation in vitro. Cell membrane sheets of hPDLSCs pretreated in two culture environments were implanted into the critical bone defects of rats skulls, tissue samples were collected after 8 weeks, and microcomputed tomography (micro-CT), HE staining, Masson staining, immunohistochemical staining and fluorescent dyes labeling new bone experiment were used to study the ability of hPDLSCs to promote osteogenic differentiation in vivo. Results: Under hypoxia conditions, the proliferation ability of hPDLSCs was increased (P＜0.05), the level of senescence was decreased (P＜0.05), and the expressions of SOX2, OCT4, and NANOG genes and proteins were all enhanced (P＜0.05). Using hPDLSCs conditioned medium cultured in hypoxia to promote hPDLSCs osteogenic differentiation in vitro, the ALP activity increased, calcium nodule formation increased (P＜0.05), and the expressions of COL-1, OPN, OCN and RUNX2 were increased (P＜0.05). After implanting the hypoxia cultured hPDLSCs cell sheets into the bone defects, new bone formation increased, the area of fluorescent emitted by new bone was larger and the intensity was stronger. Bone volume fraction of rat skull ［bone volume (BV)/tissue volume (TV)］ was significantly increased (P＜0.05), and a large number of new bone tissues at the edge of the bone defect with surrounding osteocytes and a large number of collagen fibers were observed by HE and Masson staining. Immunohistochemical results showed increased expression of OPN and OCN proteins (P＜0.05). Conclusion: Under hypoxia environment, the stemness of hPDLSCs is enhanced, and hypoxia pretreated hPDLSCs promote osteogenic differentiation of cells in vitro and in vivo.

Objective:?To investigate the effect of methylene-blue-mediated photodynamic therapy (MB-PDT) on the clearance and reformation of biofilms of Enterococcus faecalis (E. faecalis). Methods:?After establishing 24-hour bacterial biofilms of E. faecalis in vitro, the samples were divided into different groups for treatments: 0.9% NaCl; 1% NaClO; MB-PDT; 1% NaClO+MB-PDT; 50 μg/mL MB. Bacteria coating counting method was used to detect the sterility of each group. Scanning electron microscopy and confocal laser microscopy were used to assess the immediate destruction and removal effects of the first four groups on the biofilm. These groups were then allowed to continue treatment to form regenerated biofilms, and MTT and crystal violet staining were employed to detect the metabolic activity and intensity of regenerated biofilm. qRT-PCR was used to analyze the effect of MB-PDT on the expression of genes encoding collagen-binding proteins (ACE), gelatinase (GELE), and serine protease (SPRE) to the mono-species biofilm of E. faecalis. Results: Compared with the control group of 0.9% NaCl, MB-PDT destroyed the biofilm of E. faecalis and significantly reduced the bacteria count (P＜0.05); the strength and activity of the regenerated biofilm were lower than those of the control group (P＜0.05). qRT-PCR showed that the expression of genes related to biofilm formation in E. faecalis was significantly downregulated (P＜0.05). Conclusions: MB-PDT has a destructive effect on biofilms of E. faecalis and inhibits the ability of E. faecalis to reform biofilms.

Objective:?To explore the digital dynamic jaw position transfer and dynamic bite adjustment methods for patients undergoing fixed denture restoration with edentulous jaw implants.Methods:?Four to six implants were implanted in edentulous patients, and traditional methods were used to create temporary restorations immediately after surgery. Four to six months after implantation, cone beam CT, stereophotogrammetry, intraoral scanning, and mandibular movement trajectory recording were performed on the patients. These data were aligned in the design software to obtain the horizontal and vertical jaw position relationship of the temporary restoration, three-dimensional implant position information, soft tissue information, and three-dimensional data of the virtual trial occlusal frame. Combining personalized mandibular movement parameters with virtual dynamic bite adjustment to complete the final restoration. Results:The patient's final restoration achieved good occlusal contact in both centric and lateral positions. The components of the oral and maxillofacial system, such as occlusion, jaw position, temporomandibular joints, and masticatory muscles, achieved functional coordination. Conclusions:The application of digital workflow enables accurate impression production for fixed dental restorations, replicates the dynamic jaw position relationship of temporary restorations, and dynamically adjusts the bite of formal restorations. This approach optimizes the occlusal adaptability of the restoration and reduces clinical adjustment time.

Porphyromonas gingivalis （P. gingivalis） is a key pathogen in periodontal infections, with various pathogenic mechanisms such as activation of inflammatory responses, internalization of host cells to evade immune clearance, and reshaping of host cell biological behaviors. As research into microbial infections progresses, increasing evidence suggests that microbial infection is closely related to DNA damage of the host cell genome. This article aims to discuss research progress on how P. gingivalis affects DNA damage and repair capabilities of host cells from the perspective of its main pathogenicity, providing new insights for exploring the deeper pathogenic mechanisms of P. gingivalis.

Bone injury repair is a complex biological process involving various mechanisms, including immune response, angiogenesis, and bone regeneration. In recent years, lactate, as a key metabolic product, has generated significant attention for its regulatory role in bone repair. This article reviews the research progress on the multi level regulatory effects of lactate in bone injury repair, aiming to provide new perspectives and theoretical foundations for clinical treatments in bone regeneration.

The homeobox (HOX) gene family comprises a highly conserved group of transcription factors that play a pivotal role in biological processes such as embryonic development and organ formation. Recent studies have demonstrated that aberrant expression of HOX genes is closely associated with the initiation and progression of oral squamous cell carcinoma (OSCC), making them important molecular targets in OSCC research. This review summarizes the research progress on HOX genes in OSCC, with a focus on their key mechanistic roles in tumorigenesis. Furthermore, we discuss the potential of HOX genebased targeted therapeutic strategies.

The balance of microecology is of great significance, and its imbalance is closely related to the occurrence of various diseases in the whole body. During pregnancy, pregnant women will undergo corresponding changes, such as weight gain, estrogen and progesterone increase, accompanied by changes in the immune system, resulting in a series of changes in the human microecology. The interaction between the flora and the host immune system can lead to the development of disease and may be associated with a range of pregnancy complications, including gestational diabetes and preeclampsia. This paper discusses the relationship between pregnancy complications and microecology based on recent studies, and the correlation between pregnancy complications and changes in oral, intestinal and vaginal microecology of pregnant women.