Objective: To examine the effect of intracellular vesicles (IVs) and extracellular vesicles (EVs) that originated from periodontal ligament stem cells (PDLSCs) on the osteogenic differentiation of PDLSCs within a lipopolysaccharide (LPS)-simulated inflammatory microenvironment, and to provide new insights for the application of IVs in the repair and regeneration of periodontal tissue in periodontitis. Methods: Ethical approval was obtained from the institution. Human-origin PDLSCs were extracted, and the IVs and EVs from PDLSCs at the 3rd-6th passages were gathered and identified using transmission electron microscopy, nano flow cytometry (Nano FCM) analysis, and Western Blot. The 3rd-6th generations of PDLSCs were categorized into the following groups: Control group, LPS group, LPS + 100 μg/mL EVs group (LPS+EVs group), and LPS + 100 μg/mL IVs group (LPS+IVs group). The effects of the IVs and EVs on the anti-inflammatory and osteogenic differentiation of PDLSCs in an inflammatory microenvironment were assessed by using a Cell Counting Kit-8 (CCK-8), enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (qRT-PCR), Western Blot, alkaline phosphatase (ALP) staining, and alizarin red staining (ARS). Results: Under transmission electron microscopy, the IVs and EVs derived from PDLSCs displayed a double-layer membrane structure. NanoFCM analysis revealed that the average diameters of the IVs and EVs were 79.6 nm and 82.1 nm, respectively. Western Blot analysis indicated that the surface proteins CD9, CD63, and CD81 of the IVs and EVs were positively expressed, while calnexin was negatively expressed, indicating that IVs and EVs were successfully obtained. Compared with the Control group, the proliferation of PDLSCs in the LPS group was reduced, while the levels of inflammatory cytokine interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the cell supernatant were increased, the mRNA expressions of osteogenic differentiation-related genes, including osteoblast-related genes runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), osteocalcin (OCN) of PDLSCs were reduced, the protein expressions of RUNX2 and osteopontin (OPN) were also decreased (P<0.05); compared with the LPS group, the proliferation of PDLSCs in the LPS+EVs group and LPS+IVs group were significantly increased, while the levels of IL-6, TNF-α were significantly reduced, and the mRNA expressions of RUNX2, ALP, OCN were significantly increased, the protein expressions of RUNX2 and OPN were also significantly increased (P<0.05). Further, in the inflammatory microenvironment, Compared with EVs, IVs more significantly promote the proliferation of PDLSCs, inhibit TNF-α expression, enhance the expression of RUNX2 mRNA, upregulate the expression of RUNX2 and OPN proteins, increase ALP activity, and promote the formation of mineralized nodules (P<0.05). Conclusion IVs and EVs derived from PDLSCs can boost the proliferation of PDLSCs in an inflammatory microenvironment, inhibit the expression of inflammatory factors, and advance the osteogenic differentiation of PDLSCs. The anti-inflammatory and osteogenic effects of IVs are superior to those of EVs.

Periodontal disease is highly prevalent, exerting detrimental effects on oral health and posing serious threats to systemic health. Over the past three decades, research exploring the impact of periodontal disease on systemic diseases has rapidly advanced. Nevertheless, numerous challenges and unanswered questions remain, necessitating further investigation. Therefore, this article first elucidates the association between periodontal disease and systemic diseases. Then, the key evidence supporting their relationship is graded according to the Oxford Centre for Evidence-Based Medicine levels of evidence criteria. Specifically, periodontal disease emerges as an independent risk factor for diabetes mellitus (level A evidence) and cardiovascular diseases (level B evidence). As such, it represents a potential risk factor for rheumatoid arthritis (level B evidence), chronic obstructive pulmonary disease (level B evidence), and inflammatory bowel disease (level B evidence). Furthermore, periodontal disease is closely linked to adverse pregnancy outcomes. Second, this article delineates the plausible mechanisms through which periodontal disease influences systemic diseases, explicitly showing that the foundational elements underlying their connection are bacteria and inflammation. The circulation pathway and saliva pathway specifically mediate this connection. Finally, in light of the current ambiguities surrounding the relationships between periodontal disease and certain systemic diseases, as well as the insufficient depth of mechanism research, this article outlines several considerations for future clinical research and animal experiment designs. Implementing large-sample, multi-center, high-quality clinical studies, utilizing multi-omics analyses for more in-depth exploration of mechanisms, and actively promoting clinical translational research are recommended. This article aims to advance the field of periodontal medicine, while simultaneously offering evidence-based insights to inform the implementation of public health policies.

Objective: To investigate the role of butyric acid-producing bacteria in long bone homeostasis in mice with periodontitis under a high-fat/high-sugar diet and to provide new insights for the prevention and treatment of periodontitis and related bone metabolic diseases. Methods: This study has been approved by the Animal Welfare and Ethics Committee of the Experimental Animal Center. Initially, 14 mice were randomly divided into the CON group (the control group) and the LIG group (the periodontitis group). Mice in the LIG group had experimental periodontitis induced by ligating the second maxillary molars bilaterally and were fed a high-fat and high-sugar diet. After 8 weeks, samples were collected. Micro-computed tomography (Micro-CT) was used to analyze alveolar bone resorption and various parameters of the proximal tibia trabecular bone, including bone mineral density (BMD), bone volume per tissue volume (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), and trabecular separation (Tb.Sp). After decalcification, hematoxylin and eosin (HE) staining was performed on maxillary bone sections to assess periodontal tissue inflammation and connective tissue destruction. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect related genes in the distal femur and proximal tibia bone tissues, including osteocalcin (OCN), osteogenic transcription factor (Osterix), osteoprotegerin (OPG), tartrate resistant acid phosphatase (TRAP), osteoclast-associated receptor (OSCAR), receptor activator of nuclear factor kappa-B (RANK), and receptor activator of nuclear factor kappa-B ligand (RANK-L). Subsequently, the other 28 mice were randomly divided into the CON group (the control group), LIG group (the periodontitis group), CON + butyric acid-producing bacteria (BP) group, and LIG + BP group. The breeding, sampling, and sample detection methods remained the same. Finally, the other 28 mice were randomly divided into the CON group (the control group), LIG group (the periodontitis group), CON + sodium butyrate (SB) group, and LIG + SB group. The breeding, sampling, and sample detection methods remained the same. Results: ①Periodontitis modeling was successful. Compared with the CON group, the LIG group exhibited significant alveolar bone resorption of the maxillary second molar, aggravated periodontal tissue inflammation, and connective tissue destruction. ②Periodontitis exacerbated long bone resorption in mice fed a high-fat high-sugar diet. Compared with the CON group, the LIG group had significantly lower BMD, BV/TV, Tb.N, and Tb.Th (P<0.05), and significantly higher Tb.Sp (P<0.05). HE staining of the proximal tibia showed that the trabeculae in the LIG group were sparse and disordered, with some areas showing fractures or dissolution. The expression of osteoblast markers (OCN, Osterix, OPG) was significantly lower in the LIG group (P<0.05), while the expression of the osteoclast marker TRAP showed an increasing trend (P>0.05). The ratio of RANK-L/OPG was significantly higher in the LIG group compared with the CON group (P<0.05). ③ Supplementation with butyric acid-producing bacteria alleviates periodontitis-induced disruption of long bone homeostasis in mice fed a high-fat/high-sugar diet. Compared with the LIG group, BMD and Tb.Th were significantly higher in the LIG + BP group. HE staining of the proximal tibia showed that bone resorption was mitigated in the LIG + BP group compared with the LIG group. The expression of OCN and Osterix was significantly higher in the LIG + BP group, while the expression of osteoclast-specific genes (OSCAR, RANK, RANK-L) was significantly lower (P<0.05). ④ Supplementation with butyrate alleviates periodontitis-induced disruption of long bone homeostasis in mice fed a high-fat/high-sugar diet. Compared with the LIG group, BV/TV and Tb.N were significantly higher in the LIG + SB group, and Tb.Sp was significantly lower (P<0.05). HE staining of the proximal tibia showed that bone resorption was mitigated in the LIG + SB group compared with the LIG group. The expression of Osterix, OPG, OSCAR, TRAP, and RANK was significantly lower in the LIG + SB group compared with the LIG group (P<0.05). Conclusion Periodontitis disrupts the long bone homeostasis of mice fed a high-fat high-sugar diet, aggravating long bone resorption. Supplementation with butyric acid-producing bacteria or butyrate can effectively alleviate the disruption of long bone homeostasis caused by periodontitis.

Periodontitis and rheumatoid arthritis (RA) are chronic inflammatory diseases that share similar inflammatory mechanisms and characteristics. Programmed cell death (PCD) has recently garnered attention for its crucial role in regulating inflammation and maintaining tissue homeostasis, as well as for its potential to link these two diseases. The various forms of PCD--including apoptosis, pyroptosis, and necroptosis--are closely controlled by signaling pathways such as Toll-like receptor 4 (TLR4) /NF-κB and MAPK. These pathways determine cell fate and influence inflammatory responses, tissue destruction, and repair, and they both play important roles in the pathogenesis of RA and periodontitis. In periodontitis, periodontal pathogens such as Porphyromonas gingivalis (P. gingivalis) and its virulence factors, including lipopolysaccharide (LPS), induce pyroptosis and necroptosis in immune cells such as macrophages via the TLR4/NF-κB pathway, which leads to an excessive release of pro-inflammatory cytokines such as interleukin (IL)-1β and tumor necrosis factor (TNF)-α. Concurrently, these pathogens inhibit the normal apoptotic process of immune cells, such as neutrophils, prolonging their survival, exacerbating immune imbalance, and aggravating periodontal tissue destruction. Similarly, in RA synovial tissue, fibroblast-like synoviocytes (FLS) acquire apoptosis resistance through signaling pathways such as the Bcl-2 family, JAK/STAT, and NF-κB, allowing for the consistent proliferation and secretion of matrix metalloproteinases and pro-inflammatory cytokines. Meanwhile, the continuous activation of pyroptotic pathways in neutrophils and macrophages results in the sustained release of IL-1β, further exacerbating synovial inflammation and bone destruction. Notably, dysregulated PCD fosters inter-organ crosstalk through shared inflammatory mediators and metabolic networks. Damage-associated molecular patterns (DAMPs) and cytokines that originate from periodontal lesions can spread systemically, influencing cell death processes in synovial and immune cells, thereby aggravating joint inflammation and bone erosion. By contrast, systemic inflammation in RA can upregulate osteoclastic activity or interfere with the normal apoptosis of periodontal cells via TNF-α and IL-6, ultimately intensifying periodontal immune imbalance. This review highlights the pivotal bridging role of PCD in the pathogenesis of both periodontitis and RA, providing a reference for therapeutic strategies that target cell death pathways to manage and potentially mitigate these diseases.

Periodontitis is a chronic inflammatory disease of the periodontal supporting tissues caused by plaque microorganisms, whereas inflammatory bowel disease (IBD) is a chronic inflammatory disease characterized by gastrointestinal tract damage. Studies have revealed a close association between periodontitis and IBD, and gut microbiota has been shown to play an important role in the development of IBD. When the gut microbiota is disturbed, it leads to intestinal barrier disruption, triggers immune-inflammatory responses, and influences IBD progression. There are significant differences between the salivary microbiota of periodontitis patients and healthy individuals, and periodontal pathogens can enter the intestinal tract with saliva and participate in the development of IBD by influencing the interactions between gut microbiota composition, immune responses, metabolite production, and intestinal barrier function. Current gut microbiota-targeted intervention strategies, such as fecal microbiota transplantation (FMT) and probiotic supplementation, have shown potential therapeutic value in the treatment of periodontitis. These approaches may exert synergistic effects on both periodontitis and IBD through microbiota modulation. This review summarizes research progress on the relationship between periodontitis and IBD to provide a foundation for the prevention and treatment of these two diseases.

BACKGROUND:Host immune response triggered by plaque biofilm is an initiator of periodontitis progression and destruction.Macrophages are an important component of the innate immune response,which play an important role in inflammation occurrence and development. OBJECTIVE:To review the relationship between macrophage polarization and periodontitis and the related progress in the treatment of periodontitis by regulating macrophage polarization. METHODS:PubMed and CNKI databases were searched for relevant literature published from 1990 to 2023,with"macrophage polarization,M1/M2 macrophage,periodontitis,periodontitis treatment,macrophage polarization and periodontitis,osteoimmunology,ferroptosis,macrophage polarization and ferroptosis,periodontitis and ferroptosis"as the English and Chinese search terms.After the initial screening,96 articles were selected for review. RESULTS AND CONCLUSION:The switch between different phenotypes of macrophages is closely related to the tissue destruction caused by periodontitis,and various cytokines and inflammatory mediators secreted from macrophages are involved in the destruction and repair of periodontal tissue.Therefore,regulation of macrophage polarization and cytokine secretion in inflammatory state helps to alleviate periodontitis inflammation and improve the periodontal microenvironment,thereby reducing tissue destruction or promoting periodontal tissue regeneration.Many studies have been conducted to develop drugs or biomaterials to modulate macrophage function for the purpose of immunomodulatory treatment of periodontitis.However,macrophages act throughout the development of periodontitis and play an important role in the process of anti-infection,bone destruction and bone repair,and polarization is a complex and dynamic process influenced by many factors.Therefore,further exploration on possible mechanisms is still needed to clarify the interaction between materials or drugs and macrophages.

With the increasing demand for beauty,the treatment of gingival recession has become a common request among patients.Clinically,gingival recession is mainly treated by surgery.The common surgical methods include free gingival grafting,pedicled flap technology and double flap technology(subepithelial connective tissue transplantation combined with coronally advanced flaps).If patients with indications are selected,satisfactory surgical results will be ob-tained.However,there are still some shortcomings in the above mentioned methods,such as the root coverage effect not being satisfactory.In recent years,researchers have put forward some improved schemes to minimize the shortcomings of the above methods to treat different degrees of gingival recession.A gingival unit graft containing gingival papilla and free gingiva can improve the blood supply of the recipient area and improve the effect of root coverage.It can obtain bet-ter root coverage for slight retraction,widening of the angular gingiva and deepening of the vestibular sulcus,but there may be issues with inconsistent color and shape of the gingiva after surgery,as well as poor aesthetic effects.Modified coronally advanced flaps,flaps prepared by the technique of half-thickness,full-thickness and half-thickness,and modi-fied coronally advanced envelope flap technology are designed with the most serious retraction teeth as the center in the case of multiple gingival retractions,both of which can improve the effect of root covering.Tunnel technology and modi-fied tunnel technology,without severing the gingival papilla and tunneling the gingival flap to accommodate the graft,can effectively reduce tissue damage and promote wound healing.This paper reviews the literature and summarizes the outcome of the modified surgery techniques in the treatment of gingival recession.These treatment options for gingival recession are proposed with the aim of improving clinical work,and some suggestions for the treatment of gingival reces-sion to achieve a stable root coverage effect are put forward.In the future,the development direction of mucogingival surgery is to reduce trauma and have a stable curative effect.

Objective:To study the effects of periodontitis on bone and tryptophan metabolism of gut microbiota in the context of estrogen deficiency.Methods:Thirty-two female C57BL6/J mice were randomly divided into four groups based on table of random numbers ( n=8 in each group): Sham group, in which mice were given sham surgery; Sham_Lig group, in which mice were given sham surgery and were induced to periodontitis by ligating the bilateral maxillary second molars with 5-0 silk threads at the fourth week; Ovx group, in which mice were given bilateral ovariectomy; Ovx_Lig group, in which mice were given bilateral ovariectomy and were induced to periodontitis at the fourth week. After 8 weeks of ligation, the mice of 4 groups were euthanized for collecting the samples of femur, tibia, mandible and skull. Those samples were scanned by micro-CT to measure the bone mineral density (BMD), bone volume versus total volume ratio (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th) and trabecular spacing (Tb.Sp). The cecum contents of 4 groups of mice were collected for gut microbiota 16S rRNA gene sequencing. The tryptophan and its metabolites in intestinal tracts were detected by liquid chromatography-mass spectrometry. Pearson correlation analysis was performed to analyze the correlation between the abundance of gut microbiota and the content of tryptophan and its metabolites. Results:Femur BMD [(82.23±3.97) mg/cm 3], BV/TV [(9.25±1.37)%] and Tb.Th [(70.95±5.70) μm] in Ovx_Lig group were significantly lower than Ovx group [(96.30±3.76) mg/cm 3 ( P=0.004); (14.45±1.55)% ( P=0.022) and (87.58±8.02) μm ( P<0.001), respectively]. The β-diversity analysis of gut microbiota based on Bray-Curtis distance showed that samples of Ovx_Lig group and Ovx group were obviously grouped. Linear discriminant analysis effect size (LEfSe) showed that Alistipes was the representative genus in Ovx_Lig group. The relative abundance of Alistipes in Ovx_Lig group [(0.42±0.14)%] were significantly higher than that in Ovx group [(0.17±0.05)%] ( t=4.45, P<0.001). Tryptophan metabolism analysis showed that the content of kynurenic acid [(531.12±158.60) ng/g] in Ovx_Lig group were significantly higher than that in Ovx group [(400.42±57.96) ng/g] ( t=2.19, P=0.046). And the content of indole-3-carbaldehyde [(383.37±144.06) ng/g] in Ovx_Lig group were significantly lower than Ovx group [(701.72±141.93) ng/g] ( t=4.45, P<0.001). Correlation analysis showed that relative abundance of Alistipes was positively correlated with kynurenic acid ( r=0.32, P=0.088), while negatively correlated with indole-3-carbaldehyde ( r=-0.32, P=0.088). Conclusions:Periodontitis can induce bone destruction of femur in estrogen-deficient mice, the mechanism of which may be related to Alistipes in gut and the tryptophan metabolites kynurenic acid and indole-3-carbaldehyde.

Odontogenic maxillary sinusitis(OMS)is a subtype of maxillary sinusitis(MS).It is actually inflammation of the maxillary sinus that secondary to adjacent infectious maxillary dental lesion.Due to the lack of unique clinical features,OMS is difficult to distinguish from other types of rhinosinusitis.Besides,the characteristic infectious pathogeny of OMS makes it is resistant to conventional therapies of rhinosinusitis.Its current diagnosis and treatment are thus facing great difficulties.The multi-disciplinary cooperation between otolaryngologists and dentists is absolutely urgent to settle these questions and to acquire standardized diagnostic and treatment regimen for OMS.However,this disease has actually received little attention and has been underrepresented by relatively low publication volume and quality.Based on systematically reviewed literature and practical experiences of expert members,our consensus focuses on characteristics,symptoms,classification and diagnosis of OMS,and further put forward multi-disciplinary treatment decisions for OMS,as well as the common treatment complications and relative managements.This consensus aims to increase attention to OMS,and optimize the clinical diagnosis and decision-making of OMS,which finally provides evidence-based options for OMS clinical management.

Endo-periodontal lesions(EPLs)involve both the periodontium and pulp tissue and have complicated etiologies and pathogenic mechanisms,including unique anatomical and microbiological characteristics and multiple contributing factors.This etiological complexity leads to difficulties in determining patient prognosis,posing great challenges in clinical practice.Furthermore,EPL-affected teeth require multidisciplinary therapy,including periodontal therapy,endodontic therapy and others,but there is still much debate about the appropriate timing of periodontal therapy and root canal therapy.By compiling the most recent findings on the etiology,pathogenesis,clinical characteristics,diagnosis,therapy,and prognosis of EPL-affected teeth,this consensus sought to support clinicians in making the best possible treatment decisions based on both biological and clinical evidence.