Isolation, identification and osteogenic capability analysis of mesenchymal stem cells derived from different layers of human maxillary sinus membrane.

AIM: To discover the populations of mesenchymal stem cells (MSCs) derived from different layers of human maxillary sinus membrane (hMSM) and evaluate their osteogenic capability. MATERIALS AND METHODS: hMSM was isolated into a monolayer using the combined method of physical separation and enzymatic digestion. The localization of MSCs in hMSM was performed by immunohistological staining and other techniques. Lamina propria layer-derived MSCs (LMSCs) and periosteum layer-derived MSCs (PMSCs) from hMSM were expanded using the explant cell culture method and identified by multilineage differentiation assays, colony formation assay, flow cytometry and so on. The biological characteristics of LMSCs and PMSCs were compared using RNA sequencing, reverse transcription and quantitative polymerase chain reaction, immunofluorescence staining, transwell assay, western blotting and so forth. RESULTS: LMSCs and PMSCs from hMSMs were both CD73-, CD90- and CD105-positive, and CD34-, CD45- and HLA-DR-negative. LMSCs and PMSCs were identified as CD171+/CD90+ and CD171-/CD90+, respectively. LMSCs displayed stronger proliferation capability than PMSCs, and PMSCs presented stronger osteogenic differentiation capability than LMSCs. Moreover, PMSCs could recruit and promote osteogenic differentiation of LMSCs. CONCLUSIONS: This study identified and isolated two different types of MSCs from hMSMs. Both MSCs served as good potential candidates for bone regeneration.

Case report and literature review: autonomous robotic system assisted palatal implantation at an anterior teeth site compromised by periapical cyst.

Background: Immediate implant placement (IIP), which preserves gingival height and papilla shape while simultaneously accelerating the implant treatment period, has become a popular method due to its commendable clinical outcomes. Nonetheless, deploying immediate implants demands specific preconditions concerning the remaining alveolar bone. This poses a challenge to the accuracy of implant surgery. Case presentation: In this report, we present the case of a 60-year-old woman with a left upper anterior tooth crown dislodged for over a month. Cone beam computed tomography (CBCT) revealed the absence of a labial bone wall on tooth 22, a remaining 1 mm bone wall on the labial side of the root apex, and a 17.2 mm*8.9 mm*4.7 mm shadow in the periapical region of the root apices of teeth 21 and 22, with the narrowest width on the sagittal plane being approximately 5 mm. After the surgeon removed the cyst, they completed the subsequent implantation surgery using an autonomous robot in a challenging aesthetic area. This method circumvented the potential exposure of the screw thread on the labial implant surface, assured initial implant stability. Conclusion: Five months after the operation, the dental crown was restored. The implant remained stable, with yielding notable clinical results. To the best of our knowledge, this clinical case is the first to report the feasibility and precision of immediate implantation in anterior teeth site with periapical cyst removal, performed by an autonomous robotic surgical system. Autonomous robots exhibit exceptional accuracy by accurately controlling axial and angular errors. It can improve the accuracy of implant surgery, which may become a key technology for changing implant surgery. However, further clinical trials are still needed to provide a basis for the rapid development of robotic surgery field.

Black Phosphorus - A Rising Star in the Antibacterial Materials.

Antibiotics are the most commonly used means to treat bacterial infection at present, but the unreasonable use of antibiotics induces the generation of drug-resistant bacteria, which causes great problems for their clinical application. In recent years, researchers have found that nanomaterials with high specific surface area, special structure, photocatalytic activity and other properties show great potential in bacterial infection control. Among them, black phosphorus (BP), a two-dimensional (2D) nanomaterial, has been widely reported in the treatment of tumor and bone defect due to its excellent biocompatibility and degradability. However, the current theory about the antibacterial properties of BP is still insufficient, and the relevant mechanism of action needs to be further studied. In this paper, we introduced the structure and properties of BP, elaborated the mechanism of BP in bacterial infection, and systematically reviewed the application of BP composite materials in the field of antibacterial. At the same time, we also discussed the challenges faced by the current research and application of BP, which laid a solid theoretical foundation for the further study of BP in the future.

Flapless osteotome-mediated sinus floor elevation using platelet-rich fibrin versus lateral approach using deproteinised bovine bone mineral for residual bone height of 2-6 mm: A randomised trial.

OBJECTIVES: To evaluate patient-reported outcomes and radiographic results of simultaneous implant placement in severely atrophic maxilla using flapless endoscope-assisted osteotome sinus floor elevation with platelet-rich fibrin (PRF), also defined as PESS, and to compare the results with those of lateral sinus floor elevation (LSFE). METHODS: Patients with a residual bone height (RBH) of 2-6 mm were included in a randomised controlled trial. PESS was performed with PRF as the sole grafting material. LSFE was performed using deproteinised bovine bone matrix. Patient-reported outcomes were recorded on a visual analogue scale (VAS-pain) and visual rating scale (VRS-swelling and VRS-willingness). Peri-implant bone height (PBH), bone mineral density (BMD) and sinus grafting remodelling index were measured using CBCT immediately postoperatively and 3rd, 6th and 18th months post-surgery. RESULTS: The study population consisted of 20 patients in each group. The RBH of two groups averaged 3.35 ± 0.79 mm and 2.92 ± 0.63 mm with no significant difference (p > .05). VAS-pain was 18.0 (IR 15.0-22.5) and 35.0 (IR 32.5-37.0) in the PESS and LSFE groups, respectively (p < .01). VAS-pain decreased with time in both groups. VRS-swelling was lower in the PESS group than LSFE group. VRS-willingness was higher in the PESS group than LSFE group (p < .01). At 18 months post-surgery, the marginal bone loss was 0.60 ± 0.25 mm and 0.69 ± 0.35 mm in the two groups with no significant difference (p = .52). CONCLUSIONS: Within the limitations of this study, PESS was associated with lower postoperative morbidity and was more tolerable than LSFE. PESS could be a reliable procedure for sinus floor elevation in patients with insufficient RBH.

Effects of quercetin on human oral keratinocytes during re-epithelialization: An in vitro study.

BACKGROUND: The width of keratinized mucosa plays an important role in esthetic and functional outcomes of dental implants. Lack of keratinized mucosa may lead to poor oral hygiene and greater soft-tissue recession. This study aimed at assessing the potential of quercetin in promoting human oral keratinocyte (HOK) proliferation and re-epithelialization in vitro. MATERIALS AND METHODS: HOK were detected in the absence or presence of test substances. The Cell Counting Kit-8 was used to assess cell viability and proliferation capacity. Re-epithelization was assessed using a keratinocyte monolayer scratch assay. Cell migration was monitored via Transwell chambers. Porphyromonas gingivalis lipopolysaccharide was used to stimulate keratinocytes for mimicking the inflammatory situation. mRNA expression of inflammatory cytokines (interleukin-1beta, IL-1ß and tumor necrosis factor alpha, TNF-α), cell adhesion molecules (Integrin-α6, Integrin-ß4), and growth factors (transforming growth factor beta 1,TGF-ß1 and transforming growth factor beta 3, TGF-ß3) were estimated using RT-qPCR. Protein contents of TGF-ß1 and TGF-ß3 were investigated by enzyme-linked immunosorbent assay. RESULTS: Multiplex analysis revealed that quercetin enhances HOK proliferation via an upregulation of adhesion molecules (Integrin-α6ß4). Additionally, re-epithelialization rate was significantly greater in the presence of quercetin than in the control (P < 0.01). Furthermore, 20 µM of quercetin increases both mRNA and protein levels of TGF-ß3 under basal and wound conditions without affecting TGF-ß1 production. Expressions of pro-inflammatory cytokines were downregulated by quercetin treatment. CONCLUSION: Quercetin promotes HOKs proliferation and oral re-epithelialization in vitro.

Sineoculis homeobox homolog 1 protein as an independent biomarker for gastric adenocarcinoma.

Sine oculis homeobox homolog 1 (SIX1) protein is a member of the homeobox transcription factor family. Overexpression of SIX1 contributes to cancer progression and is associated with adverse outcomes in various cancer types including breast, ovarian, uterine cervical and liver. To investigate the clinicopathological significance of SIX1 protein expression in gastric adenocarcinomas (GAC), localization of the SIX1 protein was determined in MKN-1, a gastric cancer cell line, using immunofluorescence (IF) staining; SIX1 mRNA level was detected in fresh tissues of GAC and normal gastric mucosa using quantitative real-time polymerase chain reaction (qRT-PCR); and SIX1 protein expression was assessed in 163 GAC, 35 gastric dysplasia and 26 normal gastric mucosa using immunohistochemical (IHC) staining. Correlations between SIX1 protein expression and pathological parameters of GAC were analyzed using Chi-square tests, differences in survival curves were analyzed using log-rank tests, and multivariate survival analysis was performed using the Cox proportional hazards regression model. SIX1 protein showed a mainly cytoplasmic staining pattern in GAC using IF and IHC staining. The positive SIX1 protein expression rate was 80.4% in GAC, which was significantly higher than in either gastric dysplasia (45.7%) or normal gastric mucosa (26.9%) (P<0.01). qRT-PCR data also confirmed increased levels of SIX1 mRNA expression in GAC compared with the normal gastric mucosa in fresh tissues. In addition, the strongly positive SIX1 protein expression rate was significantly correlated with clinical stage, lymph node metastasis and serosal invasion of GAC (P<0.01 or P<0.05), while there was no association with gender, age, tumor size, Lauren classification or histological types of GAC. Notably, strongly positive signals were frequently observed in tumor blood vessels and/or lymphatic vessels. GAC patients with high expression of the SIX1 had shorter overall and disease-free survival rates than those with low SIX1 protein expression (P<0.01). Furthermore, using multivariate analysis, SIX1 protein expression was found to be an independent risk factor for survival in patients with GAC along with clinical stage and serosal invasion (P<0.01). In conclusion, SIX1 protein expression status may be an independent biomarker for prognostic evaluation of GAC.