The relationship between radiographic measurements of alveolar bone in posterior single-tooth edentulous regions and non-alveolar jawbones using multidetector computed tomography.

OBJECTIVE: This study aimed to evaluate the relationship between radiographic measurements of the alveolar bone in posterior single-tooth edentulous regions and radiographic measurements of non-alveolar jawbones using multidetector computed tomography (MDCT). METHODS: The sample consisted of 47 patients aged between 20 and 42 years who underwent MDCT. All patients had a posterior single-tooth edentulous region. Extraction was performed 1-8 years ago at the time of inclusion (mean = 3.2). The alveolar bone in the edentulous region and non-alveolar bone regions (maxillary tuberosity, condyles, inferior to the mandibular foramen, and mandibular angle) were studied radiographically (radiographic density, dimensions, and cortical bone ratio). Pearson correlation, independent sample t test, and linear regression analysis were used for the statistical analysis. RESULTS: Radiographic density of the alveolar bone (measured in the axial or buccolingual directions) correlated significantly with that of the maxillary tuberosity (0.3 < r < 0.4; P value ≥ 0.001) and, to a lesser extent, with the radiographic density of the region inferior to the mental foramen (r ≈ 0.3). Based on these correlation coefficients, non-alveolar bone density could explain 10-16% of the alveolar bone density after extraction according to linear regression analysis. CONCLUSIONS: This study revealed that alveolar bone radiographic density was correlated with that of the maxillary tuberosity and inferior to the mental foramen region. Accordingly, linear regression models were suggested to aid in predicting future alveolar bone density in areas where extraction is to be performed.

Potential of combined red and near-infrared photobiomodulation to mitigate pro-osteoclastic and inflammatory gene expression in human mandibular osteogenic cells.

Appropriate regeneration of jawbone after dental or surgical procedures relies on the recruitment of osteoprogenitor cells able to differentiate into matrix-producing osteoblasts. In this context, photobiomodulation (PBM) has emerged as promising therapy to improve tissue regeneration and to facilitate wound healing processes. The aim of this study was to determine the effect of PBM on human osteoprogenitor cells isolated from mandibular trabecular bone.Bone marrow stromal cell cultures were established from 4 donors and induced toward osteogenic differentiation for 14 days in a standard osteogenic assay. Cells were irradiated with a combined red/near-infrared (NIR) laser following different schedules and expression of osteogenic, matrix-related, osteoclastogenic and inflammatory genes was analyzed by quantitative PCR.Gene expression analysis revealed no overall effects of PBM on osteogenic differentiation. However, a statistically significant reduction was observed in the transcripts of COL1A1 and MMP13, two important genes involved in the bone matrix homeostasis. Most important, PBM significantly downregulated the expression of RANKL, IL6 and IL1B, three genes that are involved in both osteoclastogenesis and inflammation.In conclusion, PBM with a red/NIR laser did not modulate the osteogenic phenotype of mandibular osteoprogenitors but markedly reduced their expression of matrix-related genes and their pro-osteoclastogenic and pro-inflammatory profile.

Human Umbilical Cord Mesenchymal Stem Cells-Derived Extracellular Vesicles for Rat Jawbone Regeneration in Periapical Periodontitis.

Extracellular vesicles derived from mesenchymal stem cells (MSCs-EVs) have great potential for bone remodeling and anti-inflammatory therapy. For the repair and reconstruction of inflammatory jawbone defects caused by periapical periodontitis, bone meal filling after debridement is commonly used in the clinic. However, this treatment has disadvantages such as large individual differences and the need for surgical operation. Therefore, it is of great significance to search for other bioactive substances that can promote jawbone regeneration in periapical periodontitis. Herein, it is found that CT results showed that local injection of human umbilical cord mesenchymal stem cells-derived extracellular vesicles (HUC-MSCs-EVs) and bone meal filling into the alveolar bone defect area could promote bone tissue regeneration using a rat model of a jawbone defect in periapical periodontitis. Histologically, the new periodontal tissue in the bone defect area was thicker, and the number of blood vessels was higher by local injection of HUC-MSCs-EVs, and fewer inflammatory cells and osteoclasts were formed compared to bone meal filling. In vitro, HUC-MSCs-EVs can be internalized by rat bone marrow mesenchymal stem cells (BMSCs), enhancing the ability for proliferation and migration of BMSCs. Additionally, 20 µg/mL HUC-MSCs-EVs can facilitate the expression of osteogenic genes and proteins including runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), and osteopontin (OPN). In summary, in vivo and in vitro experiments showed that HUC-MSCs-EVs can promote bone regeneration in periapical periodontitis, and the effect of tissue regeneration is better than that of traditional bone meal treatment. Therefore, local injection of HUC-MSCs-EVs may be an effective method to promote jawbone regeneration in periapical periodontitis.

Biomechanical behavior of temporomandibular joint movements driven by mastication muscles.

Surgery of jawbones has a high potential risk of causing complications associated with temporomandibular joint disorder (TMD). The objective of this study was to investigate the effects of two drive modeling methods on the biomechanical behavior of the temporomandibular joint (TMJ) including articular disc during mandibular movements. A finite element (FE) model from a healthy human computed tomography was used to evaluate TMJ dynamic using two methods, namely, a conventional spatial-oriented method (displacement-driven) and a compliant muscle-initiated method (masticatory muscle-driven). The same virtual FE model was 3D printed and a custom designed experimental platform was established to validate the accuracy of experimental and theoretical results of the TMJ biomechanics during mandibular movements. The results show that stress distributed to TMJ and articular disc from mandibular movements provided better representation from the muscle-driving approach than those of the displacement-driven modeling. The simulation and experimental data exhibited significant strong correlations during opening, protrusion, and laterotrusion (with canonical correlation coefficients of 0.994, 0.993, and 0.932, respectively). The use of muscle-driven modeling holds promise for more accurate forecasting of stress analysis of TMJ and articular disc during mandibular movements. The compliant approach to analyze TMJ dynamics would potentially contribute to clinic diagnosis and prediction of TMD resulting from occlusal disease and jawbone surgery such as orthognathic surgery or tumor resection.

The Contribution of Meckel's Cartilage-Derived Type II Collagen-Positive Cells to the Jawbone Development and Repair.

Jawbones and long bones, despite their shared skeletal lineage, frequently exhibit distinct origins and developmental pathways. Identifying specific progenitor subsets for mandibular osteogenesis remains challenging. Type II collagen is conventionally associated with cartilaginous structures, yet our investigation has identified the presence of type II collagen positive (Col2+) cells within the jawbone development and regeneration. The role of Col2+ cells in jawbone morphogenesis and repair has remained enigmatic. In this study, we analyze single-cell RNA sequencing data from mice jawbone at embryonic day 10.5. Through fate-mapping experiments, we have elucidated that Col2+ cells and their progeny are instrumental in mandibular osteogenesis across both fetal and postnatal stages. Furthermore, lineage tracing with a tamoxifen-inducible CreER system has established the pivotal role of Col2+ cells, marked by Col2-CreER and originating from the primordial Meckel's cartilage, in jawbone formation. Moreover, our research explored models simulating jawbone defects and tooth extraction, which underscored the osteogenic differentiation capabilities of postnatal Col2+ cells during repair. This finding not only highlights the regenerative potential of Col2+ cells but also suggests their versatility in contributing to skeletal healing and regeneration. In conclusion, our findings position Col2+ cells as essential in orchestrating osteogenesis throughout the continuum of mandibular development and repair.

Osteoimmune Interaction and TH-1/TH-2 Ratio in Jawbone Marrow Defects: An Underestimated Association - Original Research.

Introduction: Osteoimmunology recognizes the relationship between bone cells and immune cells. Chronic osteoimmune dysregulation is present in bone marrow defects of the jaw (BMDJ) as fatty-degenerative osteonecrosis (FDOJ). In comparison to samples from healthy jaw bone, the cytokine analysis of samples of BMDJ/FDOJ from 128 patients showed downregulated TNF-α and IL-6 expression and the singular overexpression of the chemokine RANTES/CCL5. Aim and Objectives: This paper raises the question of whether the osteoimmune defects due to incomplete wound healing in BMDJ/FDOJ in 128 patients are related to dysregulation of the Th1/Th2 ratio and regulatory T cell (T-reg) expression in a control group of 197 BMDJ/FDOJ patients, each presenting with BMDJ/FJOD and one of seven different immune disorders. Material and Methods: In the control group, serum concentrations of the cytokines IFN-y and IL-4 were determined after stimulated cytokine release and displayed as Th1/Th2 ratios. Results: Data show a shift in Th2 in more than 80% (n = 167) of the control cohort of 197 chronically ill patients with concomitant BMDJ/FDOJ. In these 167 subjects, the Th1/Th2 ratio was <6.1 demonstrating impaired immune regulation. Forty-seven subjects or 30% showed not only a shift in Th2 but also excessive T-reg overactivation with levels of >1.900 pg/mL, indicating strongly downregulated immune activity. Discussion: BMDJ/FDOJ is characterized by a lack of Th1 cytokines and an excessive expression of RANTES/CCL5 and IL-1ra and, thus, the inversion of an acute inflammatory cytokine pattern. In contrast, abdominal fat contains a very high proportion of regulatory Th1 cells and produces an inflammatory immune response through the high overexpression of TNF-α and IL-6. The lack of Th1 activation in BMDJ/FDOJ areas inhibits normal wound healing and supports the persistence of BMDJ/FDOJ. Conclusion: The Th1/Th2 ratio requires greater consideration, especially with respect to wound healing following dental surgical interventions, such as jaw surgery, implantation and augmentation, to avoid the emergence of the osteoimmune situation that is characteristic of BMDJ/FDOJ.

Preoperative assessment of bone density for dental implantation: a comparative study of three different ROI methods.

BACKGROUND: Dental cone beam computed tomography (CBCT) is commonly used to evaluate cancellous bone density before dental implant surgery. However, to our knowledge, no measurement approach has been standardized yet. This study aimed to evaluate the relationship between three different regions of interest (ROI) methods on cancellous bone density at the dental implant site using dental CBCT images. METHODS: Patients' dental CBCT images (n = 300) obtained before dental implant surgery were processed using Mimics (Materialise, Leuven, Belgium). At the potential implant sites, the rectangle, cylinder, and surrounding cylinder ROI methods were used to measure bone density. Repeated measures one-way analysis of variance was performed to compare the three ROI methods in terms of measurement results. Pearson correlation analysis was performed to identify the likely pair-wise correlations between the three ROI methods. RESULTS: The density value obtained using the surrounding cylinder approach (grayscale value [GV],523.56 ± 228.03) was significantly higher than the values obtained using the rectangle (GV, 497.04 ± 236.69) and cylinder (GV,493 ± 231.19) ROI methods in terms of results. Furthermore, significant correlations were noted between the ROI methods (r > 0.965; p < 0.001). CONCLUSIONS: The density measured using the surrounding cylinder method was the highest. The choice of method may not influence the trends of measurement results. TRIAL REGISTRATION: This study was approved by the Institutional Review Board of China Medical University Hospital, No. CMUH111-REC3-205. Informed consent was waived by the Institutional Review Board of China Medical University Hospital, CMUH111-REC3-205, owing to the retrospective nature of the study.

Mineralised collagen regulated the secretion of adrenomedullin by macrophages to activate the PI3K/AKT signalling pathway to promote bone defect repair.

Biomaterials can affect the osteogenic process by regulating the function of macrophages and transforming the bone immune microenvironment. Mineralised collagen (MC) is an artificial bone that is highly consistent to the microstructure of the native osseous matrix. The studies have confirmed that MC can achieve effective regeneration of bone defects, but the potential mechanism of MC regulating osteogenesis is still unclear. This study confirmed that MC regulate the high expression of adrenomedullin (ADM) in macrophages and promote the osteogenic differentiation, proliferation and migration of BMSCs. Moreover, ADM activated the PI3K/Akt pathway, while the inhibition of PI3K/Akt hindered the proliferation, migration and osteogenic differentiation of BMSCs promoted by ADM. Additionally, the rat mandibular defect model confirmed that ADM promote the repair of mandibular defects, and the inhibition of PI3K/Akt pathway hinders the osteogenic effect of ADM. Our study suggests that MC regulates ADM secretion by macrophages, creates an ideal bone immune microenvironment, activates the PI3K/AKT signalling pathway, and promotes osteogenesis.

Piezo1 and Piezo2 collectively regulate jawbone development.

Piezo1 and Piezo2 are recently reported mechanosensory ion channels that transduce mechanical stimuli from the environment into intracellular biochemical signals in various tissues and organ systems. Here, we show that Piezo1 and Piezo2 display a robust expression during jawbone development. Deletion of Piezo1 in neural crest cells causes jawbone malformations in a small but significant number of mice. We further demonstrate that disruption of Piezo1 and Piezo2 in neural crest cells causes more striking defects in jawbone development than any single knockout, suggesting essential but partially redundant roles of Piezo1 and Piezo2. In addition, we observe defects in other neural crest derivatives such as malformation of the vascular smooth muscle in double knockout mice. Moreover, TUNEL examinations reveal excessive cell death in osteogenic cells of the maxillary and mandibular arches of the double knockout mice, suggesting that Piezo1 and Piezo2 together regulate cell survival during jawbone development. We further demonstrate that Yoda1, a Piezo1 agonist, promotes mineralization in the mandibular arches. Altogether, these data firmly establish that Piezo channels play important roles in regulating jawbone formation and maintenance.

Stability of standardized uptake values for quantitative bone SPECT for jawbone lesions: a single-center cross-sectional study.

BACKGROUND: The long time required for bone uptake of radiopharmaceutical material after injection for bone scintigraphy is a burden for patients with poor health. Thus, to assess whether the uptake time could be reduced for single-photon emission computed tomography (SPECT) of the jawbone, this study evaluated differences in maximum standardized uptake values (SUVmax) within patients using SPECT imaging at 2 and 3 hours after radiopharmaceutical injection. METHODS: A total of 33 patients undergoing treatment or in post-treatment follow-up for medication-related osteonecrosis of the jaw, who visited our hospital between July 2020 and August 2021 and could receive SPECT twice on the same day, were enrolled in the study. Patients were injected with technetium-99 m hydroxymethylene diphosphonate (Tc-99 m HMDP) intravenously. The SUVmax for healthy parietal bones and jawbone lesions were calculated from the SPECT images using quantitative analysis software, and the SUVmax were compared between 2- and 3-hour uptake times. RESULTS: After exclusion, 30 patients were included in the study. In the 2-hour and 3-hour images, the median SUVmax of the parietal bones were 1.90 and 1.81, respectively, and those of the jawbone lesions were 9.25 and 9.39, respectively. The limits of agreement (LOA) ranged from - 0.33 to 0.25 in the parietal bones, and the %LOA ranged from - 9.8 to 17.3% in the jawbone lesions, showing high equivalence between the two uptake durations. The SUVmax showed no clinical differences between the 2- and 3-hour uptake durations for Tc-99 m HMDP SPECT of the jawbone. CONCLUSIONS: The results of this study justify a 2-3-hour uptake window when performing quantitative SPECT of the jawbone. Therefore, the minimum uptake time can potentially be reduced to only 2 hours.

Interaction between immuno-stem dual lineages in jaw bone formation and injury repair.

The jawbone, a unique structure in the human body, undergoes faster remodeling than other bones due to the presence of stem cells and its distinct immune microenvironment. Long-term exposure of jawbones to an oral environment rich in microbes results in a complex immune balance, as shown by the higher proportion of activated macrophage in the jaw. Stem cells derived from the jawbone have a higher propensity to differentiate into osteoblasts than those derived from other bones. The unique immune microenvironment of the jaw also promotes osteogenic differentiation of jaw stem cells. Here, we summarize the various types of stem cells and immune cells involved in jawbone reconstruction. We describe the mechanism relationship between immune cells and stem cells, including through the production of inflammatory bodies, secretion of cytokines, activation of signaling pathways, etc. In addition, we also comb out cellular interaction of immune cells and stem cells within the jaw under jaw development, homeostasis maintenance and pathological conditions. This review aims to eclucidate the uniqueness of jawbone in the context of stem cell within immune microenvironment, hopefully advancing clinical regeneration of the jawbone.

Antimicrobial effects of clindamycin-loaded platelet-rich fibrin (PRF).

OBJECTIVES: Recent research has demonstrated that platelet-rich fibrin (PRF) is an appropriate carrier for ampicillin/sulbactam. The aim of the study was to investigate whether PRF is also a suitable bio-carrier for clindamycin (CLI). METHODS: PRF membranes were produced from 36 patients receiving intravenous therapy with CLI (e.g. due to the diagnosis of an osteonecrosis of the jaw or infections). Concentrations of CLI in PRF membranes were measured with liquid chromatography-tandem mass spectrometry, and the antimicrobial effects were investigated in vitro in agar diffusion tests with fresh PRF and PRF stored for 24 h. Storage was performed in an incubator at 36 °C to simulate the in-vivo situation. RESULTS: The mean concentration of CLI in plasma was 1.0 ± 0.3 µg/100 mg plasma; in resulting PRF membranes 0.7 ± 0.4 µg/100 mg PRF. Agar diffusion tests were performed with Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus mitis, Porphyromonas gingivalis, and Fusobacterium nucleatum. Mean inhibition zones, in mm, for fresh PRF were 17.3, 12.2, 18.8, 17.1, 25.8 and 18.1, 12.7, 19.2, 17.3, and 26.3 for stored PRF, respectively. CONCLUSION: The results demonstrate that PRF is a suitable bio-carrier for CLI when administered systemically to patients. The concentration in PRF generated from patients after infusion of 600 mg CLI dose suffices to target clinically relevant bacteria. CLINICAL RELEVANCE: Using PRF as a carrier for local antibiotic application can prevent infections in oral and maxillofacial surgery. Within the study limitations, the findings could expand the scope of PRF application by adding CLI as a new antibiotic to the spectrum of PRF therapy.

Investigation of clindamycin concentrations in human plasma and jawbone tissue in patients with osteonecrosis of the jaw: A prospective trial.

The aim of this study was to investigate the jawbone concentration of clindamycin (CLI) in patients with an osteonecrosis of the jaw (ONJ). Patients with medication-related ONJ (MRONJ) and osteoradionecrosis (ORN) with an antibiotic treatment with CLI were included. Plasma, vital and necrotic bone samples were collected. Plasma and jawbone samples were analyzed by liquid chromatography-tandem mass spectrometry. Patients with MRONJ exhibited a mean plasma CLI concentration of 9.6 µg/mL (SD ± 3.6 µg/mL) and mean concentrations of 2.3 µg/g CLI (SD ± 1.4 µg/g) and 2.1 µg/g CLI (SD ± 2.4 µg/g) in vital and necrotic bone samples, without statistical significance (p = 0.79). In patients with ORN, mean concentration in plasma was 12.0 µg/mL (SD ± 2.6 µg/mL), in vital bone 2.1 µg/g (SD ± 1.5 µg/g), and in necrotic bone 1.7 µg/g (SD ± 1.2 µg/g). Vital and necrotic bone concentrations did not differ significantly (p = 0.88). The results demonstrate that CLI concentrations are considerably lower than in plasma, but sufficient for most bacteria present in ONJ. Within the limitations of the study, it seems that CLI is a relevant alternative to other antibiotics in the treatment of ONJ because it reaches adequate concentrations in jawbone.

A Proof of Concept: Optimized Jawbone-Reduction Model for Mandibular Fracture Surgery.

Previous research on computer-assisted jawbone reduction for mandibular fracture surgery has only focused on the relationship between fractured sections disregarding proper dental occlusion with the maxilla. To overcome malocclusion caused by overlooking dental articulation, this study aims to provide a model for jawbone reduction based on dental occlusion. After dental landmarks and fracture sectional features are extracted, the maxilla and two mandible segments are aligned first using the extracted dental landmarks. A swarm-based optimization is subsequently performed by simultaneously observing the fracture section fitting and the dental occlusion condition. The proposed method was evaluated using jawbone data of 12 subjects with simulated and real mandibular fractures. Results showed that the optimized model achieved both accurate jawbone reduction and desired dental occlusion, which may not be possible by existing methods.

Meta-analysis of the efficacy of invisible orthodontic appliances for maxillary molar distalization in adult patients / 口腔疾病防治

Objective@#To evaluate the clinical efficacy of invisible orthodontic appliances without brackets for the distal movement of maxillary molars to improve the ability of orthodontists to predict treatment outcomes.@*Methods@#Web of Science, Cochrane Library, Embase, PubMed, Wanfang Database, CNKI Database, and VIP Database were searched for studies investigating the efficacy of invisible orthodontic appliances for distal movement of maxillary molars in adult patients and published from database inception to August 1, 2023. A total of three researchers screened the studies and evaluated their quality and conducted a meta-analysis of those that met quality standards.@*Results@#This study included 13 pre- and postcontrol trials with a total sample size of 281 patients. The meta-analysis revealed no significant differences in the sagittal or vertical parameters of the jawbone after treatment when compared with those before treatment (P>0.05). The displacement of the first molar was MD=-2.34, 95% CI (-2.83, -1.85); the displacement was MD=-0.95, 95% CI (-1.34, -0.56); and the inclination was MD=-2.51, 95% CI (-3.56, -1.46). There was a statistically significant difference in the change in sagittal, vertical, and axial tilt of the first molar before and after treatment. After treatment, the average adduction distance of the incisors was MD=-0.82, 95% CI (-1.54, -0.09), and the decrease in lip inclination was MD=-1.61, 95% CI (-2.86, -0.36); these values were significantly different from those before treatment (P<0.05).@*Conclusion@#Invisible orthodontic appliances can effectively move the upper molars in a distal direction and control the vertical position of the molars. When the molars move further away, there is some degree of compression and distal tilt movement, which is beneficial for patients with high angles. The sagittal movement of incisors is beneficial for improving the patient's profile.

Robot-assisted rehabilitation of people with breast cancer developing upper limb lymphedema: protocol of a randomized controlled trial with a 6-month follow­up.

Upper limb lymphedema (ULLy) is an external (and/or internal) manifestation of lymphatic system insufficiency and deranged lymph transport for more than 3 months and frequently affects people as a consequence of breast cancer (BC). ULLy is often underestimated despite diminished motor skills, mood, and cognitive-behavioral complaints negatively condition the health-related quality of life (HRQoL) of persons. BC can also metastasize to the jawbone, further impacting on the HRQoL. In time, the implementation of robot-assisted rehabilitation (RR) for neurological diseases has grown to improve HRQoL and pain. This study aims to evaluate the effectiveness of a RR program in the treatment of individuals who develop an ULLy; as a further analysis, the study will assess the effectiveness of the same program in people with jawbone metastases from BC who will also develop ULLy. A randomized, parallel-group superiority-controlled trial will be conducted. 44 participants will be randomly allocated to either the experimental (receiving a RR program) or the control group (regular rehabilitation). Both groups will follow individual-based programs three times a week for 10 weeks. The main outcome measure will be the Lymphedema Quality of Life Questionnaire. Secondary outcomes will be a pain intensity numerical rating scale and the Cranio-Facial Pain Disability Inventory. Evaluations are before and after training and 6 months later. Findings may provide evidence on the effectiveness of a RR program on inducing improvements in the HRQoL and pain of individuals with ULLy due to BC. People with ULLy and jawbone metastases from BC are expected for similar or higher improvements as per the same comparisons above. This trial might contribute towards defining guidelines for good clinical rehabilitation routines and might be used as a basis for health authorities' endorsements.Trial registration OSF REGISTRIES, osf-registrations-jz7ax-v1 . Registered on 26 June 2023.

Polymeric nanocomposite hydrogel scaffold for jawbone regeneration: The role of rosuvastatin calcium-loaded silica nanoparticles.

Bones are subject to different types of damages ranging from simple fatigue to profound defects. In serious cases, the endogenous healing mechanism is not capable of healing the damage or restoring the normal structure and function of the bony tissue. The aim of this research was to achieve a sustained delivery of rosuvastatin and assess its efficacy in healing bone tissue damage. Rosuvastatin was entrapped into silica nanoparticles and the system was loaded into an alginate hydrogel to be implanted in the damaged tissue. Silica nanoparticles were formulated based on a modified Stöber technique and alginate hydrogel was prepared via sprinkling alginate onto silica nanoparticle dispersion followed by addition of CaCl2 to promote crosslinking and hydrogel rigidification. The selected nanoparticle formulation possessed high % drug content (100.22±0.67%), the smallest particle size (221.00±7.30 nm) and a sustained drug release up to 4 weeks (98.72±0.52%). The fabricated hydrogel exhibited a further delay in drug release (81.52±4.81% after 4 weeks). FT-IR indicated the silica nanoparticle formation and hydrogel crosslinking. SEM visualized the porous and dense surface of hydrogel. In-vivo testing on induced bone defects in New Zealand rabbits revealed the enhanced rate of new bone tissue formation, its homogeneity in color as well as similarity in structure to the original tissue.

Bacterial distribution and inflammatory cytokines associated with oral cancer with and without jawbone invasion-a pilot study.

OBJECTIVE: To explore the bacterial and inflammatory variations in oral cancer patients with and without jawbone invasion. MATERIALS AND METHODS: A total of 20 specimens of fresh tumor tissue, including 10 from the tumor-invaded jawbone (JIOC group) and 10 without jawbone invasion (NJIOC group), were collected from oral cancer patients. Meanwhile, 10 specimens from normal oral mucosa were collected from healthy patients (control group). The microbiomic content of each sample was analyzed by 16S rRNA gene sequencing, while the expression of inflammatory cytokines was assessed using protein microarray analysis. RESULTS: There was a significant difference in ß diversity between JIOC and NJIOC groups (P < 0.05), but no difference between NJIOC and control groups. The average relative abundance of Fusobacteria and Spirochaetes was higher, while Firmicutes was lower in the JIOC group than in the NJIOC group (all P < 0.05). The expression of pro-inflammatory cytokines like interleukin (IL)-1α, IL-1ß, IL-4, and IL-8 was upregulated in the JIOC group compared with the NJIOC group, while MCP-1 was decreased (all P < 0.05). Slackia spp. and Howardella spp. were positively correlated with IL-4; Odoribacter spp. and Acidaminococcaceae spp. were negatively correlated with IL-4, and Clostridium XIVa spp. was negatively correlated with IL-1α and IL-1ß. CONCLUSION: Bacterial and inflammatory differences were observed in oral cancer patients with and without jawbone invasion, where the relative abundance of the differential bacteria was associated with the expression of the inflammatory cytokines. CLINICAL RELEVANCE: This study investigated the changes in the flora during jawbone invasion in oral cancer and its effect on inflammatory factors, elucidating the possible mechanisms of jawbone invasion caused by oral cancer, which may lead to new ideas for the clinical prevention and treatment of jawbone invasion in oral cancer.

Isopsoralen promotes osteogenic differentiation of human jawbone marrow mesenchymal cells through Notch signaling pathway.

BACKGROUND: The aim of this study was to investigate the effect of isopsoralen on osteogenic differentiation of human jawbone marrow mesenchymal cells and its possible mechanism. METHOD: The cytotoxicity and proliferation of cells were measured by a cell counting kit 8. Alkaline phosphatase activity analysis was then used to determine the optimal concentration of isopsoralen to promote the differentiation. Western blot, qRT-PCR and Alizarin Red S staining were used to evaluate the role of Notch signaling pathway in isopsoralen-induced osteogenic differentiation. This study also investigated the anti-osteoporotic effects of ISO using in vivo osteoporosis models. RESULTS: Our results showed that 1 × 10-6 mol / L isopsoralen can effectively promote the proliferation and osteogenic differentiation of cells. Moreover, we found that activation of notch signaling pathway inhibited isopsoralen-induced osteogenesis and inhibition of Notch signal promoted the differentiation of osteoblasts induced by isopsoralen. In vivo experiments revealed that ISO significantly inhibited OVX-induced bone mineral density loss and restored the impaired bone structural properties in osteoporosis model mice. CONCLUSION: Our findings demonstrated that isopsoralen induced osteogenic differentiation by inhibiting Notch signaling and it might be a potential therapeutic agent for treating or preventing osteoporosis.

Reduction of Inflammatory RANTES/CCL5 Serum Levels by Surgery in Patients with Bone Marrow Defects of the Jawbone.

Purpose: The presence of bone marrow defects of the jawbone (BMDJ) is associated with increased levels of inflammatory cytokines such as RANTES/CCL5. The purpose of this study was to analyze if BMDJ therapy under real-world conditions reduces RANTES/CCL5 serum levels in BMDJ patients. Patients and Methods: During this retrospective study, 113 BMDJ patients received either no treatment (n = 57), BMDJ surgery (n = 25), tooth extraction (n = 20), or root canal treatment (n = 11). Serum concentrations of RANTES/CCL5, C-reactive protein (CRP), and Tumor Necrosis Factor-α (TNF-α) were assessed before and after treatment (interventional group) and at the beginning and end of the study period (control group). Statistical analyses of the results were performed by the two-sample t-test and Bonferroni post hoc test with ANOVA for multiple comparisons. Results: BMDJ were detected in all patients with 4.42 ± 2.75 BMDJ findings per patient. RANTES/CCL5 levels were significantly reduced by any treatment when compared to no treatment (p < 0.001; effect size d = 0.90). This effect was most pronounced in the BMDJ surgery group (p < 0.001; effect size d = 1.30). In contrast, RANTES/CCL5 serum concentrations further increased in untreated patients. Mean duration between pre- and post-treatment RANTES/CCL5 measurements was 22.86 ± 19.36 weeks, with no correlation with RANTES/CCL5 levels in any interventional group or in the total sample (p = 0.104). Conclusion: BMDJ surgery, tooth extraction, and root canal treatment significantly reduce RANTES/CCL5 serum concentrations in BMDJ patients, with surgery being most beneficial. Further research is required to establish regular RANTES/CCL5 assessments as part of an improved diagnosis, monitoring, and evaluation of therapy success in BMDJ patients.