A new classification of mandible defects and condyle changed after mandible reconstruction with FFF.

Objectives: To explore a new classification of mandibular defects and changes in the preserved condyle after mandibular reconstruction with free fibular flap(FFF). Study design: We reviewed patients who underwent mandibular reconstruction with FFF from 2015 to 2021 and classified the mandibular defects into five categories: classⅠ(unilateral-mandibular excluding condyle), classⅡ(unilateral-mandibular including condyle), classⅢ(bilateral-mandibular excluding condyle), classⅣ(bilateral-mandibular including one condyle), and classⅤ(bilateral-mandibular including both condyles). Cone Beam Computed Tomography (CBCT) data were collected preoperatively(T0), at 7-10 postoperative days(T1), 6 postoperative months(T2), and 1 postoperative year(T3). We calculated the condylar surface area, volume, and displacement. Results: 62 cases were collected. The condylar surface areas and volumes in T2 and T3 values were lower than those of T0 and T1(P < 0.01) The condylar displacement was the lowest in ClassI and the largest in ClassⅣ(P < 0.01), while no significant differences in classesⅠ-Ⅲ(P < 0.05). Displacement during T1-T0 was greater than that during T2-T0 and T3-T0(P < 0.05). Conclusion: Mandibular reconstruction with FFF results in displacement and alteration of the condyle within a time interval, and this alteration stabilizes after 6 months. Mandibular defects that do not reach the midline, surgical alteration to preserve the condyle are not required. However, when the defects cross the midline, the condyle should be preserved as much as possible.

Effect of surgery-first approach on quality of life and mental health of orthognathic patients: A systematic review and meta-analysis.

Objectives: This study intends to explore the effects of the surgery-first approach (SFA) on quality of life and mental health of patients who undergo orthognathic surgery compared to the conventional three-stage approach (CTA). Data: The analysis included eight studies with a total of 307 patients, of which one was randomized controlled trial (RCT), one was clinical controlled trial (CCT), and six were non-randomized studies of interventions (NRSIs). Sources: Electronic databases such as Medline, Embase, Scopus, and Web of Science were searched for eligible trials up to April 2023. Study selection: RCTs, CCTs, and NRSIs, which compared the quality of life or mental health of orthognathic patients treated with SFA and CTA, were included in this study. The meta-analysis showed that the standardized mean differences (SMD) of Oral Health Impact Profiles-14 (OHIP-14) scores and the Orthognathic Quality of Life Questionnaire (OQLQ) between SFA and CTA were -1.58 (P = 0.05) and -2.99 (P < 0.00001) at the termination of the first-stage treatment, which altered to -0.94 (P = 0.54) and 0.09 (P = 0.65) after total treatment. Two studies applied the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) and the Beck Depression Inventory (BDI-II) to examine mental health, resulting in a trend similar to the former scales. Conclusion: In contrast to the conventional procedure, orthognathic treatment with SFA can instantly enhance the quality of life at the end of the first-stage treatment but has similar effects after the overall treatment. Moreover, SFA has a positive impact on psychological conditions. Clinical significance: This study first systematically reviewed the effect of SFA on patients' mental well-being. According to our findings, it is better to select SFA if possible. Otherwise, the patient's psychological condition should be monitored appropriately throughout decompensation for better well-being both physically and mentally.

Mortality and associated influencing factors among oral cancer patients in western China: A retrospective cohort study from 2016 to 2021.

Few studies have examined oral cancer-related mortality in Guangxi. This study aimed to explore the incidence and characteristics of oral cancer and to identify the risk factors for oral cancer-related mortality. The study was conducted to provide a reference for clinical treatment and to improve the survival rate of patients with oral cancer. A total of 271 patients with oral cancer who were treated in the Stomatology Hospital of Guangxi Medical University from 2016 to 2017 were selected as the research subjects. The follow-up lasted until the middle of 2021. The survival rate and mean survival time of 271 patients were calculated by the Kaplan-Meier method. Cox proportional hazard models and stratified analysis were used to explore the related factors that affect the mortality of patients. Nomogram plots were used to visualize the relationships among multiple variables. Among 271 patients with oral cancer, the 2-year and 5-year overall survival rates were 83.8% and 68.5% respectively. The results of multivariate analysis showed that, age, pathological type, surgery and readmission were significant factors affecting survival. When the above factors were incorporated into nomogram plots and stratified analysis, the results showed that the risk of death after treatment in patients with oral cancer aged > 55 years was 1.693 times higher than that in patients aged ≤ 55 years (HR, hazard ratio [HR] = 1.795, 95% confidence intervals [CI] = 1.073, 3.004). The risk of death after surgical treatment was 0.606 times higher than that without surgical treatment (HR = 0.590, 95% CI = 0.367, 0.948). Patients who were readmitted had a 2.340-fold increased risk of death compared with patients who were not readmitted (HR = 2.340, 95% CI = 1.267,4.321). Older age, surgery, and readmission were risk factors for mortality among patients with oral cancer. The median survival time of 271 patients with oral cancer was 52.0 months. Patients under the age of 55 years old and those who choose surgical treatment tend to have a better prognosis and a longer survival. Oral cancer-related mortality is affected by age, treatment mode, readmission, and other factors. All of these factors are worthy of clinical attention for their prevention and control.

Three-dimensional analysis of the morphological changes of the craniofacial jaw and condyle in patients with idiopathic condylar resorption.

In this study we aim to describe the three-dimensional analysis of condylar deformation of the temporomandibular joint (TMJ) and morphological changes of the craniofacial jaw in patients with idiopathic condylar resorption (ICR). We also compare those with a control group that is healthy and matched for age and gender. Cone-beam computed tomography (CBCT) and cephalometric radiograph (X-ray) were conducted and analysis of craniofacial measurement, condylar width, length, height, and condylar axial angle changes were done three-dimensionally using ProPlan CMF™ 3.0 software (Materialise). The craniofacial jaw measurements of the ICR patients were significantly different than the control group and the significant changes in the mandible can be seen in ICR patients according to the results of this study. The results of smaller condylar width and height in the ICR group reflect the smaller size of the condyle compared with an unaffected condyle. Also, both right and left sagittal condylar angles (p = 0.001 and p = 0.003), respectively, and axial condylar angles (p = 0.01 and p = 0.02), respectively, displayed significant differences between the two groups. In conclusion, the vertical development of the condyle decreased along with reduced measurements in the width and height of the condyle in ICR patients, and differences in the morphology of the craniofacial jaw and condylar angles were observed between study groups.

Mandibular reconstruction after excision of recurrent odontogenic keratocyst using a novel mandibular distraction osteogenesis method- a case report.

BACKGROUND: Odontogenic keratocyst is one of the most common benign odontogenic neoplasms with a high recurrence rate. Its resection has the potential to lead to mandibular segmental defects. In this case report, we describe a patient with odontogenic keratocyst who underwent radical resection using a novel distraction osteogenesis (DO) method to reconstruct mandibular segmental defect. CASE PRESENTATION: This case report describes a 19-year-old woman with odontogenic keratocyst of the mandible that recurred after multiple curettages and eventually necessitated radical resection. Mandibular segmental defect after radical resection was reconstructed using a novel DO method that involved directly contacting the segment ends of the defect without the transport disk. However, the distractor broke during the retention period, and a molding titanium plate was used for fixation. This novel distraction method achieved mandibular reconstruction and restored mandibular function and contour.

Association of interleukin-10 rs1800896, rs1800872, and interleukin-6 rs1800795 polymorphisms with squamous cell carcinoma risk: A meta-analysis.

The relationship between interleukin (IL)-10 and IL-6 gene polymorphisms and squamous cell carcinoma (SCC) has been demonstrated but with inconsistent conclusions. The aim of this study was to evaluate the potential associations of IL gene polymorphisms and the SCC risk. PubMed, Cochrane Library, Web of Science, China National Knowledge Infrastructure, China Biomedical Database, WanFang, and China Science and Technology Journal Database databases were searched for articles reporting the correlations of IL-10 and IL-6 gene polymorphisms with the SCC risk. Odds ratio and 95% confidence interval were calculated using Stata Version 11.2. Meta-regression, sensitivity, and publication bias were analyzed. False-positive reporting probability and Bayesian measure of the false-discovery probability were used to explore the credibility of the calculation. Twenty-three articles were included. The IL-10 rs1800872 polymorphism showed a significant correlation with the SCC risk in the overall analysis. Studies pooled by ethnicity revealed that the IL-10 rs1800872 polymorphism reduced the SCC risk in the Caucasian population. The results of this study suggest that the IL-10 rs1800872 polymorphism may confer a genetic susceptibility to SCC, particularly oral SCC, in Caucasians. However, the IL-10 rs1800896 or IL-6 rs1800795 polymorphism was not significantly associated with the SCC risk.

Correlation analysis of upper airway morphology in patients with obstructive sleep apnea and anatomically small retruded mandibles.

OBJECTIVE: To investigate the relationship between upper airway morphology and the severity of obstructive sleep apnea (OSA) in patients with anatomically small retruded mandibles. METHODS: Fifty-two patients with small retruded mandibles underwent polysomnography and airway computed tomography. The airway morphology parameters and sleep assessment were compared between the patients with or without OSA. RESULTS: Twenty-eight patients diagnosed with OSA, according to polysomnography, had a higher distance between the hyoid bone and mandibular plane (HMP), lateral dimension (LAT)/anteroposterior dimension (AP), but lower minimum cross-sectional area (mCSA), AP, surface area, volume, avgCSA, and airway uniformity (U). The apnea-hypopnea index had negative correlations with mCSA, AP, surface area, volume, avgCSA, and U, and had a positive correlation with HMP and LAT/AP. CONCLUSION: OSA is common among patients with small retruded mandibles and is associated with a more compressed upper airway shape and longer HMP.

Augmented reality hologram combined with pre-bent distractor enhanced the accuracy of distraction vector transfer in maxillary distraction osteogenesis, a study based on 3D printed phantoms.

Background: Vector control is a significant concern in maxillary distraction osteogenesis (DO). Distraction vector planning on the patient's 3D-printed skull phantom is more intuitive for surgeons and cost-efficient than virtual surgical planning. However, the accuracy of transferring the planned vector to intraoperative (vector transfer) according to the shape of the pre-bent footplate alone is relatively limited. The application of augmented reality (AR) in surgical navigation has been studied for years. However, few studies have focused on its role in maxillary DO vector transfer. This study aimed to evaluate the accuracy of AR surgical navigation combined with the pre-bent distractor in vector transfer by comparing it with the pre-bent distractor alone. Methods: Ten patients with maxillary hypoplasia were enrolled with consent, and three identical 3D-printed skull phantoms were manufactured based on per patient's corresponding pre-operative CT data. Among these, one phantom was for pre-operative planning (n = 10), while and the other two were for the AR+Pre-bending group (n = 10) and the Pre-bending group (n = 10) for the experimental surgery, respectively. In the Pre-bending group, the distraction vector was solely determined by matching the shape of footplates and maxillary surface. In the AR+Pre-bending group, the distractors were first confirmed to have no deformation. Then AR surgical navigation was applied to check and adjust the vector in addition to the steps as in the Pre-bending Group. Results: For the angular deviation of the distraction vector, the AR+Pre-bending group was significantly smaller than the Pre-bending group in spatial (p < 0.001), x-y plane (p = 0.002), and y-z plane (p < 0.001), and there were no significant differences in the x-z plane (p = 0.221). The AR+Pre-bending group was more accurate in deviations of the Euclidean distance (p = 0.004) and the y-axis (p = 0.011). In addition, the AR+Pre-bending group was more accurate for the distraction result. Conclusions: In this study based on 3D printed skull phantoms, the AR surgical navigation combined with the pre-bent distractor enhanced the accuracy of vector transfer in maxillary DO, compared with the pre-bending technique alone.

Exosomal long noncoding RNAs MAGI2-AS3 and CCDC144NL-AS1 in oral squamous cell carcinoma development via the PI3K-AKT-mTOR signaling pathway.

BACKGROUND: Long noncoding RNAs (lncRNAs) are essential and critical components of signal and transduction, regulating the intracellular microenvironment. Serum exosomes (SEs) are involved in rearranging the intercellular functional lncRNAs, which may also play a role in oral squamous cell carcinoma (OSCC). The function of lncRNAs at the transcription level in SEs of patients with OSCC is partially understood. MATERIALS AND METHODS: The lncRNA expression profiles were examined derived from SEs from patients with OSCC with lymph node metastasis (OSCC-LNM), OSCC with no LNM (OSCC-NLNM), postoperative metastasis and recurrence OSCC (rOSCC) and healthy controls (HCs). Bioinformatics analysis was used to analyse differentially expressed lncRNAs (DE lncRNAs) and a total of 150 subjects were enrolled for RT-PCR verifications. The correlations of four lncRNAs and clinicopathologic factors, biochemical indexes were evaluated. MAGI2-AS3 and CCDC144NL-AS1 were overexpressed or silenced in oral cancer (OC) cells. The proliferation, invasion, and migration were evaluated to investigate the effect of MAGI2-AS3 and CCDC144NL-AS1 on the development of OSCC. The related proteins of PI3K-AKT-mTOR signal pathway were also detected. RESULTS: The expressions of the lncRNAs, namely MAGI2-AS3 and CCDC144NL-AS1, were significantly upregulated in rOSCC and OSCC-LNM. MAGI2-AS3 was overexpressed in cancer tissue compared to other control groups. AC109587.1 and AC010978.1 were significantly associated with the clinical stage, and CCDC144NL-AS1 was significantly associated with aging. MAGI2-AS3 and CCDC144NL-AS1 might promote cell proliferation, invasion, and migration in OSCC cells by regulating the PI3K-AKT-mTOR pathway. CONCLUSIONS: our results suggest that MAGI2-AS3 an d CCDC144NL-AS1 may have clinical applications in the treatment of OSCC.

Promotion of osteogenesis in BMSC under hypoxia by ATF4 via the PERK-eIF2α signaling pathway.

Mandibular distraction osteogenesis (MDO) is an endogenous tissue engineering technology in which bone marrow mesenchymal stem cells (BMSC) play a key role in MDO-related osteogenesis. Activating transcription factor 4 (ATF4) is involved in osteogenesis through activation of PERK (Protein kinase R-like endoplasmic reticulum kinase) in endoplasmic reticulum stress (ERS) condition under hypoxia. However, the specific role of ATF4 in MDO with BMSC remains unknown. The aim of this study was to explore the effects of ATF4 in MDO with BMSC under hypoxia. Briefly, canine BMSCs were cultured in a hypoxic chamber, and effects of hypoxia were evaluated using cell migration assay and Alizarin Red S staining. Expression levels of protein kinase R-like endoplasmic reticulum kinase, eukaryotic translation initiation factor 2α, ATF4, osteocalcin, and bone sialoprotein were evaluated using quantitative polymerase chain reaction and western blotting. BMSCs were transduced with the ATF4-small interfering RNA lentivirus. The effects were evaluated using all the aforementioned experiments. The results showed that hypoxia promoted migration, osteoblast differentiation, and ATF4 expression in BMSC. ATF4 knockdown in BMSC significantly inhibited migration and osteoblast differentiation abilities, while hypoxia reversed these effects to some extent. In addition, the molecular mechanism partly depended on the ERS signaling pathway, with ATF4 as the key factor. In summary, we presented a novel mechanism of ATF4-mediated regulation of BMSC under hypoxia.

ECFC-derived exosomal THBS1 mediates angiogenesis and osteogenesis in distraction osteogenesis via the PI3K/AKT/ERK pathway.

Background: Distraction osteogenesis (DO) is a widely used bone regenerative technique. However, the DO process is slow, and the consolidation phase is long. Therefore, it is of great clinical significance to explore the mechanism of DO, and shorten its duration. Recent studies reported that stem cell exosomes may play an important role in promoting angiogenesis related to DO, but the mechanism remains unclear. Methods: Canine endothelial colony-forming cells (ECFCs) were isolated and cultured, and the expression of THBS1 in canine ECFCs were inhibited using a lentiviral vector. The exosomes secreted by canine ECFCs were isolated and extracted, and the effect of exosomes on the angiogenic activity of Human umbilical vein endothelial cells (HUVECs) was detected by proliferation, migration, and tube formation experiments. WB and qRT-PCR were used to explore the effects and mechanisms of THBS1-mediated ECFC-Exos on HUVECs angiogenesis. Then, a mandibular distraction osteogenesis (MDO) model was established in adult male beagles, and exosomes were injected into the canine peripheral blood. Micro-CT, H&E, Masson, and IHC staining were used to explore the effects and mechanisms of THBS1-mediated ECFC-Exos on angiogenesis and osteogenesis in the DO area. Results: ECFC-Exo accelerated HUVECs proliferation, migration and tube formation, and this ability was enhanced by inhibiting the expression of THBS1 in ECFC-Exo. Using Western blot-mediated detection, we demonstrated that inhibiting THBS1 expression in ECFCs-Exo activated PI3K, AKT, and ERK phosphorylation levels in HUVECs, which promoted VEGF and bFGF expressions. In the DO model of the canine mandible, ECFCs-Exo injected into the peripheral blood aggregated into the DO gap, thus promoting angiogenesis and bone formation in the DO tissue by reducing THBS1 expression in ECFC-Exo. Conclusion: Our findings suggested that ECFC-Exos markedly enhances angiogenesis of endothelial cells, and promotes bone healing in canine MDO. Thus, THBS1 plays a crucial role in the ECFC-Exos-mediated regulation of canine MDO angiogenesis and bone remodeling. The translational potential of this article: This study reveals that the angiogenic promotion via THBS1 suppression in ECFC-Exos may be a promising strategy for shortening the DO duration.

Hsp20 Promotes Endothelial Progenitor Cell Angiogenesis via Activation of PI3K/Akt Signaling Pathway under Hypoxia.

BACKGROUND: Mandibular distraction osteogenesis (MDO) is a kind of endogenous tissue engineering technology that lengthens the jaw and opens airway so that a patient can breathe safely and comfortably on his or her own. Endothelial progenitor cells (EPCs) are crucial for MDO-related angiogenesis. Moreover, emerging evidence suggests that heat shock protein 20 (Hsp20) modulates angiogenesis under hypoxic conditions. However, the specific role of Hsp20 in EPCs, in the context of MDO, is not yet known. The aim of this study was to explore the expression of Hsp20 during MDO and the effects of Hsp20 on EPCs under hypoxia. METHODS: Mandibular distraction osteogenesis and mandibular bone defect (MBD) canine model were established. The expression of CD34, CD133, HIF-1α, and Hsp20 in callus was detected by immunofluorescence on day 14 after surgery. Canine bone marrow EPCs were cultured, with or without optimal cobalt chloride (CoCl2) concentration. Hypoxic effects, caused by CoCl2, were evaluated by means of the cell cycle, cell apoptosis, transwell cell migration, and tube formation assays. The Hsp20/KDR/PI3K/Akt expression levels were evaluated via immunofluorescence, RT-qPCR, and western blot. Next, EPCs were incorporated with either Hsp20-overexpression or Hsp20-siRNA lentivirus. The resulting effects were evaluated as described above. RESULTS: CD34, CD133, HIF-1α, and Hsp20 were displayed more positive in the callus of MDO compared with MBD. In addition, hypoxic conditions, generated by 0.1 mM CoCl2, in canine EPCs, accelerated cell proliferation, migration, tube formation, and Hsp20 expression. Hsp20 overexpression in EPCs significantly stimulated cell proliferation, migration, and tube formation, whereas Hsp20 inhibition produced the opposite effect. Additionally, the molecular mechanism was partly dependent on the KDR/PI3K/Akt pathway. CONCLUSION: In summary, herein, we present a novel mechanism of Hsp20-mediated regulation of canine EPCs via Akt activation in a hypoxic microenvironment.

Identification of the key exosomal lncRNAs/mRNAs in the serum during distraction osteogenesis.

BACKGROUND: Distraction osteogenesis (DO), a kind of bone regenerative process, is not only extremely effective, but the osteogenesis rate is far beyond ordinary bone fracture (BF) healing. Exosomes (Exo) are thought to play a part in bone regeneration and healing as key players in cell-to-cell contact. The object of this work was to determine whether exosomes derived from DO and BF serum could stimulate the Osteogenic Differentiation in these two processes, and if so, which genes could be involved. METHODS: The osteogenesis in DO-gap or BF-gap was evaluated using radiographic analysis and histological analysis. On the 14th postoperative day, DO-Exos and BF-Exos were isolated and cocultured with the jaw of bone marrow mesenchymal stem cells (JBMMSCs). Proliferation, migration and osteogenic differentiation of JBMMSCs were ascertained, after which exosomes RNA-seq was performed to identify the relevant gene. RESULTS: Radiographic and histological analyses manifested that osteogenesis was remarkably accelerated in DO-gap in comparison with BF-gap. Both of the two types of Exos were taken up by JBMMSCs, and their migration and osteogenic differentiation were also seen to improve. However, the proliferation showed no significant difference. Finally, exosome RNA-seq revealed that the lncRNA MSTRG.532277.1 and the mRNA F-box and leucine-rich repeat protein 14(FBXL14) may play a key role in DO. CONCLUSIONS: Our findings suggest that exosomes from serum exert a critical effect on the rapid osteogenesis in DO. This promoting effect might have relevance with the co-expression of MSTRG.532277.1 and FBXL14. On the whole, these findings provide new insights into bone regeneration, thereby outlining possible therapeutic targets for clinical intervention.

A Review Into the Insights of the Role of Endothelial Progenitor Cells on Bone Biology.

In addition to its important transport functions, the skeletal system is involved in complex biological activities for the regulation of blood vessels. Endothelial progenitor cells (EPCs), as stem cells of endothelial cells (ECs), possess an effective proliferative capacity and a powerful angiogenic capacity prior to their differentiation. They demonstrate synergistic effects to promote bone regeneration and vascularization more effectively by co-culturing with multiple cells. EPCs demonstrate a significant therapeutic potential for the treatment of various bone diseases by secreting a combination of growth factors, regulating cellular functions, and promoting bone regeneration. In this review, we retrospect the definition and properties of EPCs, their interaction with mesenchymal stem cells, ECs, smooth muscle cells, and immune cells in bone regeneration, vascularization, and immunity, summarizing their mechanism of action and contribution to bone biology. Additionally, we generalized their role and potential mechanisms in the treatment of various bone diseases, possibly indicating their clinical application.

microRNA-146a mediates distraction osteogenesis via bone mesenchymal stem cell inflammatory response.

Distraction osteogenesis (DO) is a widely used surgical technique to repair bone defects, partly owing to its high efficiency in inducing osteogenesis; however, the process of osteogenesis is complex, and the precise mechanism is still unclear. Among the factors identified for an effective DO procedure, well-controlled inflammation is essential. We aimed to explore how microRNA(miR)-146a, a negative regulator of inflammation, influences osteogenesis in DO. First, we established canine right mandibular DO and bone fracture models to evaluate the expression level of miR-146a in response to these procedures. Second, bone marrow mesenchymal stem cells (BMSCs) were isolated from healthy puppies and cultured with lipopolysaccharide (LPS) to observe how inflammation affects osteogenesis. Finally, the osteogenesis activity of BMSCs transfected with lentiviral vector either overexpressing (miR-146a-up) or inhibited for miR-146a expression was evaluated. miR-146a-up-transfected BMSCs were injected locally into the distraction gaps of the DO model canines. On days 42 and 56 post-surgery, the bone volume/tissue volume and bone mineral density values were evaluated via using micro-computed tomography, and newly formed tissues were harvested and evaluated via histological staining. The expression of miR-146a in both the DO canine model and LPS-stimulated BMSCs increased. Overexpression of miR-146a enhanced cell proliferation, migration, and osteogenic differentiation. Additionally, the newly formed callus was improved in canine mandibles injected with miR-146a-up-transfected BMSCs. In summary, miR-146a regulates mandibular DO by improving osteogenesis, and can serve as a potential target to shorten the therapy period of DO.

Experts' consensus on precaution and treatment for complications of sagittal split ramus osteotomy.

Sagittal split ramus osteotomy (SSRO) is a versatile orthognathic procedure for correcting mandibular deformities. Various complications can possibly occur when performing SSRO, and it can even cause serious adverse consequences because of the complexity of anatomy and operative procedures. The types of complications and their accompanying clinical manifestations are closely related to the choice of diagnosis and treatment strategies and clinical outcomes. To discuss the causes, prevention, and treatment measures of various common complications of SSRO, domestic orthognathic surgery experts prepared this consensus to increase the awareness of SSRO complications, thereby ensuring safe surgical procedure and good results.

Panax notoginseng Saponin Promotes Bone Regeneration in Distraction Osteogenesis via the TGF-ß1 Signaling Pathway.

Distraction osteogenesis (DO) is an efficient strategy that is employed for the treatment of large bone defects in craniomaxillofacial surgery. Despite its utility, however, DO is associated with a prolonged consolidation phase and a high complication rate that hinder its more widespread utilization. Panax notoginseng saponin (PNS) is a traditional Chinese medicine that is frequently administered for the treatment of a range of conditions. Herein, we explored the ability of PNS treatment to influence osteogenic differentiation using both rabbit bone marrow mesenchymal cells (BMSCs) and a model of mandibular DO. BMSC proliferation was assessed via CCK-8 assay, while osteogenic differentiation was monitored through ALP and alizarin red S staining. A PCR approach was used to evaluate the expression of genes associated with osteogenesis (ALP, Runx2, and OCN) and genes linked to the TGF pathway (TßR-II, SMAD2, SMAD3, and PPM1A). For in vivo experiments, treated BMSCs were locally injected into the DO gap, with PNS being injected into treated rabbits every other day throughout the experimental period. The quality of the regenerative process was assessed via scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray imaging, and hematoxylin and eosin (H&E) staining. These analyses revealed that PNS was able to promote BMSC osteogenesis and mandibular generation, driving the upregulation of osteogenesis-related genes at the mRNA levels through the modulation of the TGF-ß1/Smad pathway. Consistently, the overexpression or silencing of TßR-II in PNS-treated BMSCs was sufficient to modulate their osteogenic potential. Analyses of in vivo mandibular DO outcomes revealed significantly augmented new bone growth in the PNS-treated group relative to control animals, with maximal osteogenesis in the group overexpressing rabbit TßR-II. Together, these results highlight the PNS as a promising and cost-effective therapeutic tool with the potential to enhance bone regeneration in clinical contexts through the modulation of the TGF-ß1/Smad pathway.

The RNA Methyltransferase METTL3 Promotes Endothelial Progenitor Cell Angiogenesis in Mandibular Distraction Osteogenesis via the PI3K/AKT Pathway.

Distraction osteogenesis (DO) is used to treat large bone defects in the field of oral and maxillofacial surgery. Successful DO-mediated bone regeneration is dependent upon angiogenesis, and endothelial progenitor cells (EPCs) are key mediators of angiogenic processes. The N6-methyladenosine (m6A) methyltransferase has been identified as an important regulator of diverse biological processes, but its role in EPC-mediated angiogenesis during DO remains to be clarified. In the present study, we found that the level of m6A modification was significantly elevated during the process of DO and that it was also increased in the context of EPC angiogenesis under hypoxic conditions, which was characterized by increased METTL3 levels. After knocking down METTL3 in EPCs, m6A RNA methylation, proliferation, tube formation, migration, and chicken embryo chorioallantoic membrane (CAM) angiogenic activity were inhibited, whereas the opposite was observed upon the overexpression of METTL3. Mechanistically, METTL3 silencing reduced the levels of VEGF and PI3Kp110 as well as the phosphorylation of AKT, whereas METTL3 overexpression reduced these levels. SC79-mediated AKT phosphorylation was also able to restore the angiogenic capabilities of METTL3-deficient EPCs in vitro and ex vivo. In vivo, METTL3-overexpressing EPCs were additionally transplanted into the DO callus, significantly enhancing bone regeneration as evidenced by improved radiological and histological manifestations in a canine mandibular DO model after consolidation over a 4-week period. Overall, these results indicate that METTL3 accelerates bone regeneration during DO by enhancing EPC angiogenesis via the PI3K/AKT pathway.

Serum exosome-derived biomarkers for the early detection of oral squamous cell carcinoma.

Blood exosomes help regulate communication between tumour cells, moderating their behaviour. We sought to determine the protein content in serum exosomes (SEs), to characterise SEs, and to discover novel clinical biomarkers of oral squamous cell carcinoma (OSCC). Differentially expressed proteins (DEPs) of OSCC were identified using proteomics and then analysed using bioinformatics, before validation using ELISA, IHC, and RT-PCR. The influence of SEs on oral cancer cells was detected using CCK-8 and migration assays. Twelve DEPs were found in SEs from OSCC. Four proteins were targeted for further verification. New biomarkers exhibiting high sensitivity and specificity in diagnosing OSCC comprised C-reactive protein (CRP), von willebrand factor (VWF), and leucine-rich alpha-2-glycoprotein (LRG). Combined biomarkers outperformed any single protein. We also demonstrated that tumour-derived exosomes promoted tumour cell migration, but not proliferation and apoptosis. Our study indicates that CRP, VWF, and LRG are potential clinically relevant OSCC biomarkers. OSCC-related SEs may help promote migration of oral cells.