Soft tissue inflammation around upper third molar cause limited mouth opening: common but overlooked.

OBJECTIVES: The aim of this study was to explore inflammation of soft tissue around the upper third molar as a prevalent cause of limited mouth opening, identify the clinical and radiographic features, and summarize the therapeutic effectiveness of tooth extraction. MATERIALS AND METHODS: A retrospective analysis of data from 264 patients with limited mouth opening over the last five years was performed. RESULTS: Among the 264 patients, 24 (9.1%) had inflammation of the soft tissue around the upper third molar, which was the second most common cause of limited mouth opening. Twenty-one of the twenty-four affected patients, with an average mouth opening of 19.1 ± 7.6 mm, underwent upper third molar extraction. Gingival tenderness around the upper third molar or maxillary tuberosity mucosa was a characteristic clinical manifestation (p < 0.05). The characteristic features on maxillofacial CT included soft tissue swelling around the upper third molar and gap narrowing between the maxillary nodules and the mandibular ascending branch. Post extraction, the average mouth opening increased to 31.4 ± 4.9 mm (p < 0.05), and follow-up CT demonstrated regression of the inflammatory soft tissue around the upper third molar. CONCLUSIONS: Inflammation of soft tissue around the upper third molar is a common cause of limited mouth opening. Symptoms of pain associated with the upper third molar and distinctive findings on enhanced maxillofacial CT scans are crucial for diagnosis. Upper third molar extraction yields favorable therapeutic outcomes. CLINICAL RELEVANCE: Inflammation of the soft tissue around the maxillary third molar commonly causes limited mouth opening, but this phenomenon has long been overlooked. Clarifying this etiology can reduce the number of misdiagnosed patients with restricted mouth opening and enable more efficient treatment for patients.

In situ tissue profile of rat trigeminal nerve in trigeminal neuralgia using spatial transcriptome sequencing.

BACKGROUND: Trigeminal neuralgia (TN) is the most common neuropathic disorder in the maxillofacial region. The etiology and pathogenesis of TN have not been clearly determined to date, although there are many hypotheses. OBJECTIVE: The goal of this study was to investigate the interactions between different types of cells in TN, particularly the impact and intrinsic mechanism of demyelination on the trigeminal ganglion, and to identify new important target genes and regulatory pathways in TN. METHODS: TN rat models were prepared by trigeminal root compression, and trigeminal nerve tissues were isolated for spatial transcriptome sequencing. The gene expression matrix was reduced dimensionally by PCA and presented by UMAP. Gene function annotation was analyzed by Metascape. The progression of certain clusters and the developmental pseudotime were analyzed using the Monocle package. Modules of the gene coexpression network between different groups were analyzed based on weighted gene coexpression network analysis and assigned AddModuleScore values. The intercellular communication of genes in these networks via ligand-receptor interactions was analyzed using CellPhoneDB analysis. RESULTS: The results suggested that the trigeminal ganglion could affect Schwann cell demyelination and remyelination responses through many ligand-receptor interactions, while the effect of Schwann cells on the trigeminal ganglion was much weaker. Additionally, ferroptosis may be involved in the demyelination of Schwann cells. CONCLUSIONS: This study provides spatial transcriptomics sequencing data on TN, reveals new markers, and redefines the relationship between the ganglion and myelin sheath, providing a theoretical basis and supporting data for future mechanistic research and drug development.

Constrast-enhanced computed tomography radiomics predicts CD27 expression and clinical prognosis in head and neck squamous cell carcinoma.

Objective: This study aimed to construct a radiomics model that predicts the expression level of CD27 in patients with head and neck squamous cell carcinoma (HNSCC). Materials and methods: Genomic data and contrast-enhanced computed tomography (CT) images of patients with HNSCC were downloaded from the Cancer Genome Atlas and Cancer Imaging Archive for prognosis analysis, image feature extraction, and model construction. We explored the potential molecular mechanisms underlying CD27 expression and its relationship with the immune microenvironment and predicted CD27 mRNA expression in HNSCC tissues. Using non-invasive, CT-based radiomics technology, we generated a radiomics model and evaluated its correlation with the related genes and HNSCC prognosis. Results and conclusion: The expression level of CD27 in HNSCC may significantly influence the prognosis of patients with HNSCC. Radiomics based on contrast-enhanced CT is potentially effective in predicting the expression level of CD27.