This study aimed to investigate how long non-coding RNA (lncRNA) maternally expressed gene 3 (MEG3) inhibits the growth and metastasis of oral squamous cell carcinoma (OSCC) by regulating WNT/β-catenin signaling pathway in order to explore the antitumor effect of MEG3 and to provide a potential molecular target for the treatment of OSCC. The RT-qPCR technique was used to quantitatively analyze the expression of MEG3 in cancer and adjacent tissues collected from the patients after surgery. Using the Lipofectamine method, the MEG3 overexpression vector and the siRNA interference vector were constructed and transfected into SCC15 and Cal27 cells, respectively, followed by cell proliferation, apoptosis and metastasis analyses. The semi-quantitative analysis of the expression of the β-catenin protein in transfected cells was performed by the western blot analysis, and the activity of the WNT/β-catenin signaling pathway was analyzed using the TOP/FOP flash reporters. In addition, the cells were treated with decitabine to investigate the correlation between the MEG3 expression and the DNA methylation. Results showed that the expression level of MEG3 was significantly decreased in OSCC (p<0.05) and overexpression of MEG3 inhibited the proliferation and metastasis of cancer cells and promoted apoptosis. Importantly, MEG3 played a role as a tumor suppressor by inhibiting the WNT/β-catenin signaling pathway. In addition, the expression of the MEG3 was significantly affected by the degree of DNA methylation. It was concluded that the lncRNA MEG3 can inhibit the growth and metastasis of OSCC by negatively regulating the WNT/β-catenin signaling pathway.
Titanium meshes are widely utilized in alveolar bone augmentation, and this study aims to enhance the properties of titanium meshes through heat treatment (HT) and the synergistic finishing technology of electric field and flow field (EFSF). Our findings illustrate that the titanium mesh exhibits improved mechanical properties following HT treatment. The innovative EFSF technique, in combination with HT, has a substantial impact on improving the surface properties of titanium meshes. HT initiates grain fusion and reduces surface pores, resulting in enhanced tensile and elongation properties. EFSF further enhances these improvements by significantly reducing surface roughness and eliminating adhered titanium powder, a byproduct of selective laser melting printing. Increased hydrophilicity and surface-free energy are achieved after EFSF treatment. Notably, the EFSF-treated titanium mesh exhibits reduced bacterial adhesion and is non-toxic to osteoblast proliferation. These advancements increase its suitability for clinical alveolar bone augmentation.
We explored the impact of cusp inclinations on dental fractures in cracked tooth syndrome model and formulated corresponding risk scale. Forty maxillary premolars were randomized into four groups for cusp inclination measurements by digital radiovisiography (RVG). For cracked tooth models, buccal and palatal cusp inclinations were achieved by grinding in groups I (59°-50°), II (64°-55°) and III (69°-60°), with group IV as blank control. All groups underwent compression loading test, with fracture levels recorded for statistical analysis. The fracture modes included a majority of crown root fractures and a minority of crown fractures in groups I and II, exclusive crown root fractures in group III, and exclusive crown fractures in group IV. Overall, palatal fractures were predominant versus buccal fractures, with exclusive palatal fractures in group IV, and oblique fractures were overwhelming versus the scanty vertical fractures. Fracture risk classification: grade III was prevalent in groups I and II, grade IV in group III, and grades I and II in group IV only. The fracture risk scores in groups III and IV had significant statistical differences versus groups I and II (P<0.05), with insignificant differences between groups I and II, respectively (P>0.05). Cracked teeth are more vulnerable to complex fractures, with increment of cusp inclinations contributable to complex fracture modes, involving deep roots and high risk scores.
The effect of attachment positions on anchorage has not been fully explored. The aim of the present study is to analyze the effect of overtreatment with different anchorage positions on maxillary anchorage enhancement with clear aligners in extraction cases.Models of the maxilla and maxillary dentition were constructed and imported into SOLIDWORKS software to create periodontal ligament (PDL), clear aligners, and attachments. Attachment positions on second premolars included: without attachment (WOA), buccal attachment (BA), and bucco-palatal attachment (BPA). Overtreatment degrees were divided into five groups (0°, 1°, 2°, 3°, 4°) and added on the second premolars. The calculation and analysis of the displacement trends and stress were performed using ANSYS software.Distal tipping and extrusion of the canines, and mesial tipping and intrusion of the posterior teeth occurred during retraction. A strong anchorage was achieved in cases of overtreatment of 2.8° with BA and 2.4° with BPA. Moreover, the BPA showed the best in achieving bodily control of the second premolars. When the overtreatment was performed, the canines and first molars also showed reduced tipping trends with second premolars attachments. And the stress on the PDL and the alveolar bone was significantly relieved and more evenly distributed in the BPA group.Overtreatment is an effective means for anchorage enhancement. However, the biomechanical effect of overtreatment differs across attachment positions. The BPA design performs at its best for stronger overtreatment effects with fewer adverse effects.
The success of bioengineered dental pulp depends on two principles, (1) whether the transplanted tissue can develop its own vascular endothelial tubule network and (2) whether the host vasculature can be induced to penetrate the bioengineered pulp replacement and conjoin. Major inductive molecules that participate in laying down blood vessels include vascular endothelial growth factor (VEGF), ephrinB2, and hypoxia-inducible factor 1α (HIF-1α). Being able to modulate the genes encoding these angiogenic molecules is a therapeutic target in pulp regeneration for endogenous blood vessel formation, prevention of graft rejection, and exclusion of infection. Once implanted inside the root canal, bioengineered pulp is subjected to severe hypoxia that causes tissue degeneration. However, short-term hypoxia is known to stimulate angiogenesis. Thus, it may be feasible to prime dental cells for angiogenic activity before implantation. Stem cells from apical papilla (SCAP) are arguably one of the most potent and versatile dental stem cell populations for bioengineering pulp in vitro. Our study aimed to investigate whether coculture of SCAP and human umbilical vein endothelial cells (HUVECs) under hypoxia promotes the formation of endothelial tubules and a blood vessel network. In addition, we clarified the interplay between the genes that orchestrate these important angiogenic molecules in SCAP under hypoxic conditions. We found that SCAP cocultured with HUVEC at a 1:5 ratio increased the number of endothelial tubules, tubule lengths, and branching points. Fluorescence staining showed that HUVEC formed the trunk of tubular structures, whereas SCAP located adjacent to the endothelial cell line, resembling the pericyte location. When we used CoCl2 (0.5 mM) to induce hypoxic environment, the expression of proteins, HIF-1α and VEGF, and transcript of ephrinB2 in SCAP was upregulated. However, minimal VEGF levels in supernatants of HUVEC and coculture Petri dishes were detected, suggesting that VEGF secreted by SCAP might be used by HUVEC to accelerate the formation of vessel-like structures. Taken together, we revealed that artificial hypoxia stimulates angiogenic responses in SCAP for possible use in engineering dental pulp replacements. Our results may help to delineate the optimal therapeutic target to promote angiogenesis so that future bioengineered pulp replacements integrate faster and permanently within the host.