Background: Epithelial–mesenchymal transition (EMT) enables tumor cell invasion and metastasis. Many studies have demonstrated the critical role of EMT in lymph node metastasis in oral squamous cell carcinoma (OSCC). During EMT, epithelial cancer cells lose intercellular adhesion and apical–basal polarity and acquire mesenchymal properties such as motility and invasiveness. A significant feature of EMT is cadherin switching, involving the downregulation of E-cadherin and upregulation of N-cadherin. The TGF-β/SMAD pathway can also induce EMT. We aimed to evaluate EMT markers as predictors of lymph node metastasis in OSCC. Methods: We performed genetic profiling of 159 primary OSCCs from TCGA and analyzed the expression of EMT markers, including cadherin switch genes (CDH1, CDH2), and TGF-β/SMAD pathway genes. Samples were divided into advanced (stage III–IV) and early (stage I–II) stage groups. Differential expression analysis was performed, as well as an independent validation study containing fresh OSCC samples. Results: TGF-β/SMAD pathway genes such as SMAD6 were upregulated in advanced stage tumors. N-cadherin and SNAIL2 were overexpressed in node-positive tumors. Keratins were downregulated in these groups. Conclusion: Our findings demonstrate that EMT marker expression correlates with lymph node metastasis in OSCC. Developing therapies targeting regulators such as N-cadherin may prevent metastasis and improve outcomes.

Background: The aim of this study was to examine whether the thickness of the preoperative soft tissue affects the degree of soft tissue movement relative to the hard tissue movement after orthognathic surgery. Methods: This is a retrospective examination of lateral cephalometric X-rays of patients who underwent orthognathic surgery in single medical center, during a 5-year period. Demographic and operative data were collected. Soft tissue thickness was measured in preoperative cephalometric X-ray, followed by superimposition of postoperative (>6 months) cephalometric X-rays by overlapping fixed bony points. Results: In the upper jaw, there was a decrease in the relative movement of soft tissue with an increase in the initial thickness in surgeries performing advancements up to 5 mm (r = −0.288). In mandibular advancements, there was a clear decrease in soft tissue movement ratio with an increase in the initial soft tissue thickness (r = −0.418), while there was no correlation in mandibular setback cases (r = 0.062). The same correlation between the decrease in relative soft tissue movement and the increase in initial soft tissue thickness was found in advancement genioplasty (r = −0.411). Conclusion: This research shows a general pattern of decrease in relative movement of soft tissue in orthognathic surgery correlated to an increase in its initial thickness.

Background and Objectives: Oral Squamous Cell Carcinoma (OSCC) requires early diagnosis for favorable outcomes, but global healthcare disruptions caused by the COVID-19 pandemic severely affected cancer care delivery. This study aimed to investigate the pandemic’s influence on OSCC pathological staging and disease-related characteristics at a single medical center. Materials and Methods: A retrospective study was conducted on 148 patients who underwent curative-intent surgery for newly diagnosed OSCC between March 2018 and October 2024. Patients were stratified into a Pre-COVID-19 group (March 2018–January 2020, N = 52) and a Post-COVID-19 group (February 2020–October 2024, N = 96). Patient demographics and risk factors were compared using Chi-squared and Wilcoxon rank-sum tests, while pathological stage, Depth of Invasion (DOI), and surgical outcomes were analyzed. Results: Patient demographics, risk factors, and comorbidities were comparable between the two groups. The Post-COVID-19 cohort presented with significantly more advanced pathological disease, evidenced by an increase in overall TNM stage, including a dramatically higher rate of Stage 4 diagnosis (35% vs. 3.2% in the Pre-COVID-19 group). This group also showed a significantly higher Depth of Invasion (median DOI: 5.0 mm vs. 3.0 mm). Consequently, the Post-COVID-19 group required more aggressive treatment (e.g., higher rates of adjuvant radiotherapy) and experienced worse short-term outcomes, including significantly longer hospitalization (median 15 days vs. 6 days) and higher rates of postoperative pulmonary infection and tracheostomy. Conclusions: The COVID-19 pandemic was associated with a dramatic shift toward the diagnosis of OSCC at advanced pathological stages. This diagnostic delay necessitated more complex surgical management and resulted in significantly worse short-term outcomes. These findings underscore the urgent need for resilient strategies to prevent systemic diagnostic delays during public health crises.