Background and Clinical Significance: Local anesthetic injections, routine in dental practice, ensure pain control during procedures like root canal treatments. Though generally safe, they can occasionally cause hematomas, localized blood accumulations in tissue planes. Rapidly expanding hematomas in the head and neck are exceptionally rare but dangerous due to anatomical complexity, potentially threatening the airway. This case report emphasizes the critical need for the prompt recognition and management of such complications to prevent life-threatening outcomes, highlighting vigilance in routine dental procedures. Case Presentation: A 63-year-old male presented with rapidly enlarging right buccal swelling four hours post-local anesthetic injection for a root canal on a right maxillary molar. Examination showed warm, erythematous edema and buccal ecchymosis; a CT scan confirmed a 3.8 cm × 8.4 cm × 5.5 cm buccal space hematoma. His medical history revealed controlled type 2 diabetes and hyperlipidemia, and his coagulation was normal. Conservative management failed as the hematoma progressed, limiting mouth and eye opening. Urgent surgical decompression under general anesthesia evacuated clots and ligated facial and angular arteries. ICU monitoring ensured airway stability, with discharge on day three with antibiotics and follow-up. Conclusions: This case highlights the rare potential for dental anesthetic injections to cause rapidly progressive hematomas, requiring urgent surgical intervention and multidisciplinary care to prevent airway compromise. Early recognition, imaging, and decisive management are vital in achieving favorable outcomes in such serious complications.

Oral squamous cell carcinoma (OSCC) prognosis remains limited by TNM staging alone. We conducted a systematic review and meta-analysis to evaluate preoperative neutrophil-to-lymphocyte (NLR), platelet-to-lymphocyte (PLR) and lymphocyte-to-monocyte (LMR) ratios as prognostic markers. We searched PubMed/MEDLINE, Scopus, Base, Google Scholar and ScienceDirect from inception to 30 May 2026. Eligible studies reported preoperative ratios and survival outcomes, namely, overall survival (OS), disease-specific survival (DSS) and disease-free survival (DFS), in surgically treated OSCC. Risk of bias was assessed with the QUIPS tool. Random-effects meta-analyses of multivariate hazard ratios (HRs) were primary; univariate data, heterogeneity, prediction intervals, sensitivity and subgroup analyses were also performed. Thirty-nine studies (12,153 patients; mostly East Asian retrospective cohorts) were included. Elevated NLR predicted worse overall survival (HR 1.51, 95% CI 1.32–1.73) and disease-specific survival (HR 2.00, 1.58–2.54). NLR also showed a significant association with DFS (HR = 1.47, 95% CI: 1.21–1.78), though the prediction interval crossed unity. PLR and LMR showed weaker, less consistent associations. Evidence was limited by predominant retrospective design, geographic concentration and variable cut-offs. Preoperative NLR is a reproducible, inexpensive prognostic biomarker that may complement TNM staging; standardized thresholds require prospective validation. The review was registered in PROSPERO; no specific funding was received.