The pterygomandibular raphe (PMR) has traditionally been described as a fibrous or tendinous band connecting the bucinator (BM) and superior pharyngeal constrictor (SPCM) muscles. However, recent evidence has questioned its existence. This study aimed to reevaluate the anatomy of the pterygomandibular region by preserving fascial continuity and examining the relationships among adjacent muscles and connective tissues. Twenty-five sides from formalin-fixed cadaveric heads were examined. Twenty sides underwent macroscopic dissection under a surgical microscope, and five sides were sectioned axially and analyzed histologically using Masson's trichrome staining to assess muscle-fascia continuity. The buccopharyngeal fascia (BpF) adhered tightly to the posterolateral surface of the BM. A ligament-like bundle observed between the BM and medial pterygoid muscle corresponded to an artificial continuation of the BpF created by dissection. Axial sections revealed that the BpF, masseteric, and temporalis fasciae converged anteriorly on the lateral surface of the BM, while posteriorly, the BpF and temporalis fascia also merged, forming a confluence of fasciae. No discrete tendinous or ligamentous PMR was identified. The so-called PMR represents a dissection artifact rather than a true anatomical structure. These findings emphasize the importance of preserving fascial relationships and using precise terminology in anatomical and clinical contexts.

The lingual artery (LA) is depicted as originating from the anterior wall of the external carotid artery (ECA) as well as the superior thyroid and the facial arteries (FA) in anatomy textbooks and atlases. During super selective intra-arterial chemotherapy to the LA, surgeons empirically rotate the catheter medially but not for other anterior branches of the ECA. This study aimed to quantitatively investigate the degree of the LA at its origin for catheter rotation during super selective intra-arterial chemotherapy. Twenty-six halves from 14 formalin-fixed cadaveric heads were dissected. The origin of the LA and other anterior branches was observed laterally. The ECA was then incised in the axial plane at the origins of the superior and inferior margins of the anterior branches. The angles of the anterior branches in the axial plane were calculated. The relative height of LA compared to the carotid bifurcation and FA origin varied. The LA tended to originate more medially than the other anterior branches of the ECA. The mean angle difference between the LA and the other anterior branches of the ECA was approximately 40°. The LA originating from the linguofacial trunk traveled medially at its origin. The quantitative data provide anatomical evidence for the catheter rotation technique used to access the LA during a super selective intra-arterial chemotherapy.

Oral mucositis is a frequent and debilitating adverse event observed in patients undergoing chemotherapy or radiotherapy. Current management strategies are limited in duration, require frequent application, and fail to address the mechanical irritation from teeth. A novel device, Soft Protector CPC, was developed to overcome these limitations. This multicenter, randomized, two-arm, open-label, confirmatory trial aims to evaluate the efficacy and safety of Soft Protector CPC in patients with breast cancer undergoing chemotherapy. A total of 154 participants will be randomly assigned in a 1:1 ratio to receive either oral care with Soft Protector CPC or oral care alone. The primary endpoint will be oral mucositis as assessed according to the Common Terminology Criteria for Adverse Events (CTCAE) v3.0 during the comparative treatment period. The secondary endpoints will include CTCAE v3.0 during the continuous treatment period, oral mucositis, pain (CTCAE v5.0), quality of life (Patient Reported Outcomes-CTCAE version 1.0 [PRO-CTCAE v1.0], the 15-item oral health questionnaire of the European Organization For Research And Treatment Of Cancer [EORTC QLQ-OH15], and the pain Numeric Rating Scale), onset and site of mucositis, completion of chemotherapy, use of rescue medications, technical feasibility, and patient preference. The safety endpoints will include adverse events, device malfunction, and laboratory tests. This trial is expected to establish the clinical utility of the Soft Protector CPC for the prevention and management of oral mucositis, with the potential to improve the patients' quality of life and adherence to cancer therapy. This study was approved by the Clinical Research Review Board and registered with the Japan Registry of Clinical Trials, jRCTs062250005, on April 18, 2025.

Odontogenic myxofibroma (OMF) is a rare benign mesenchymal odontogenic tumor characterized by myxoid stroma with a prominent fibrous component. Although it usually arises intraosseously within the jaws, the peripheral variant, peripheral odontogenic myxofibroma (POMF), which occurs in extraosseous soft tissues, is uncommon and may be clinically misdiagnosed as a reactive gingival lesion. We report a case of POMF in a 68-year-old man who was referred for evaluation of a painless, slowly enlarging swelling of the palatal gingiva in the left maxillary second premolar region, which had initially been diagnosed as chronic periodontitis at a local clinic. An intraoral examination revealed an elastic, firm mass with partial erythema on the palatal marginal gingiva. Panoramic radiography showed mild generalized horizontal bone loss without lesion-specific changes, and computed tomography revealed no bone resorption associated with the lesion. Exfoliative cytology was negative for intraepithelial lesions or malignancy. The lesion was excised with a 5-mm clinical margin, including periosteum, and superficial peripheral ostectomy of the adjacent cortical bone was performed. Histopathological examination revealed a myxoid stroma rich in mucinous matrix and collagen fibers, containing sparsely distributed spindle-shaped cells and scattered nests of odontogenic epithelium. Alcian blue staining revealed diffuse positivity, supporting the diagnosis of POMF. No recurrence was observed during a 2-year follow-up period. This case highlights a diagnostic pitfall in the tooth-bearing gingiva and underscores the importance of histopathological confirmation of persistent gingival masses. When imaging shows no apparent bone involvement, and clinical suspicion of malignancy is low, complete excision with an adequate soft-tissue margin and selective, limited bone removal may achieve local control while preserving the adjacent teeth; long-term follow-up remains advisable.

Hyperplastic dental follicle (HDF) is a rare odontogenic hamartomatous lesion typically associated with unerupted teeth in children and adolescents and is often found incidentally on radiographic imaging. HDF usually presents as a pericoronal radiolucency of 2-3 mm in diameter and is commonly difficult to distinguish from dentigerous cysts on radiographs. We report an unusual case of HDF in an 11-year-old male who was referred for evaluation of delayed eruption of the left maxillary canine. Panoramic radiography and cone-beam computed tomography (CBCT) revealed a remarkably large radiolucent area, with a maximum dimension of 25.3 mm. The initial clinical diagnosis was a dentigerous cyst; however, incisional biopsy revealed solid tissue characteristics, and histopathological examination confirmed HDF, with no evidence of cystic lining, neoplastic transformation, or inflammation. Following the patient's and parents' preference for complete removal, resection of the lesion together with extraction of the impacted canine was performed under general anesthesia. At the 6-month follow-up, no recurrence was observed and bone regeneration was confirmed on radiographic examination. This case underscores the diagnostic challenge posed by atypical radiographic findings and highlights the necessity of histopathological confirmation. Given the exceptional size and potential for recurrence, long-term follow-up is warranted.

Mesenchymal stem cells (MSCs) are essential stromal regulators that coordinate tissue repair, angiogenesis, and immune balance. Within tumours, MSCs remodel the microenvironment and influence disease progression, yet their systemic contribution remains unclear due to the limited recovery of functional MSCs in conventional bone marrow transplantation models. Here, we developed an improved bone marrow collection (iBMC) method using enzymatic digestion, which markedly increases MSC yield while preserving their native phenotype. GFP bone marrow chimeric mice generated by iBMC and conventional transplantation displayed comparable hematopoietic reconstitution but differed in MSC abundance, enabling direct analysis of MSC-specific effects under physiological conditions. In mouse models of oral squamous cell carcinoma (OSCC), MSCs profoundly affected tumour development. MSC-deficient tumours exhibited necrosis and infiltration of immature myeloid-derived suppressor cells (MDSCs), whereas MSC-rich tumours showed enhanced vascularisation, adaptive immune infiltration, and stromal remodelling. Notably, lung metastasis occurred only in MSC-rich mice, accompanied by bone marrow–derived endothelial activation and TNF-α–driven inflammation. Pharmacological inhibition of LepR signalling using SHU9119 unexpectedly increased metastasis, underscoring the dual, context-dependent functions of MSCs. These findings establish iBMC as a reproducible and physiologically relevant model to study MSC-mediated regulation of tumour immunity, angiogenesis, and metastasis.

Oral lichen planus is a chronic inflammatory disease of the oral mucosa characterised by immune dysregulation, but its pathogenesis remains incompletely understood and no curative treatment has been established. Our previous work showed that patients with oral lichen planus exhibit gut dysbiosis, including reduced microbial diversity and depletion of butyrate-producing bacteria. Because butyrate promotes regulatory T-cell differentiation and supports immune homeostasis, targeting this dysbiosis may represent a microbiota-directed approach for immune modulation in oral lichen planus. This study aims to investigate the effects of inulin supplementation on the gut microbiota and related immune markers in patients with oral lichen planus. This multicentre, double-blind, randomised, placebo-controlled parallel-group trial will enrol 80 patients with oral lichen planus. Participants will be randomly assigned in a 1:1 ratio to receive either inulin (8 g/day) or a maltose placebo for 4 weeks, in addition to standard care. The primary outcome is the change in the relative abundance of prespecified butyrate-producing gut bacteria from baseline to the end of intervention at Week 6. Secondary outcomes include changes in gut microbiota diversity, salivary microbiota composition, faecal short-chain fatty acid concentrations, peripheral blood regulatory T-cell counts, blood test parameters, and clinical symptoms of oral lichen planus. Analyses will follow the intention-to-treat principle, and between-group differences will be assessed using appropriate statistical methods. This trial is designed to evaluate, in a randomised placebo-controlled setting, whether a microbiota-directed intervention can modify gut microbial profiles and related immune markers in patients with oral lichen planus. The findings are expected to clarify whether inulin supplementation can modify gut microbial profiles and related immunological markers in patients with oral lichen planus. Trial registration: UMIN Clinical Trials Registry (UMIN-CTR), UMIN000060840, registered on 1 April 2026 (https://rctportal.mhlw.go.jp/detail/um?trial_id=UMIN000060840#).

Three-dimensional virtual surgical planning (3D-VSP) is increasingly used in orthognathic surgery; however, procedure-specific evidence regarding its real-world impact on operative efficiency and intraoperative blood loss remains limited. This study evaluated the association between 3D-VSP implementation and operative time, and intraoperative blood loss across different orthognathic procedures. This retrospective cohort study included consecutive patients who underwent orthognathic surgery at a single academic institution before (2019–2020) and after (2023–2024) the full implementation of 3D-VSP integrated with in-house additive manufacturing (n = 344). Procedure-specific multivariable linear regression analyses were performed, adjusting for age, sex, and surgeon experience. After 3D-VSP implementation, operative time was reduced by approximately 36 min in sagittal split ramus osteotomy (SSRO), 50 min in Le Fort I (LF1) combined with SSRO, and 42 min in segmental LF1 combined with SSRO, representing a 15–20

OBJECTIVES:To compare the number of dissected cervical lymph nodes in the anatomical level III with that in supraomohyoid neck dissection (SOHND) level III affected by the anatomical relationship between the omohyoid muscle and cricoid cartilage using contrast-enhanced CT (CE-CT) images to assess the validity of the current SOHND. METHODS:CE-CT images of the patients who suffered from malignant tumours in the oral and maxillofacial regions were reviewed. The number of cervical lymph nodes both in the anatomical level III (area between the centre of the inferior border of the hyoid bone [HB] and the inferior border of the cricoid cartilage [CC]) and SOHND level III (area between HB and the intersection of the omohyoid muscle and internal jugular vein [OM-IJ]) were recorded, respectively. RESULTS:The rate of patients whose number of lymph nodes in level III was affected by the positional relationship between the OM-IJ and CC was almost equal in males and females. As for the patients with OM-IJ below the CC, the number of lymph nodes in SOHND level III increased from that of anatomical level III. Females showed significantly higher values than males (P < .05). Meanwhile, for patients with OM-IJ at or above the CC, the number of lymph nodes in SOHND level III decreased from that of anatomical level III. CONCLUSIONS:The number of dissected cervical lymph nodes differed between the SOHND dissection area and levels I, II, and III. In most cases, SOHND dissects more cervical lymph nodes, especially in female patients.

Background:Carcinoma ex pleomorphic adenoma (CXPA) is an uncommon malignant salivary gland tumor arising from pleomorphic adenoma, whereas epithelial-myoepithelial carcinoma (EMC) is a rare low-grade salivary gland malignancy. CXPA with an EMC component in the submandibular gland is uncommon. Case Report:A 65-year-old man presented with a painless, firm mass in the left submandibular region and weakness of the left lower lip. Computed tomography and magnetic resonance imaging demonstrated an irregular submandibular mass, and FDG-PET/CT showed increased uptake (maximum standardized uptake value, 9.2). Core biopsy suggested pleomorphic adenoma; however, the clinical and radiological findings strongly indicated malignancy. Incisional biopsy was therefore performed under general anesthesia, with a plan to proceed to definitive treatment if malignancy was confirmed. Intraoperative histopathological examination revealed a malignant salivary gland tumor, and tumor resection with neck dissection was completed during the same procedure. Histopathological examination showed invasive CXPA with an EMC component, accompanied by extracapsular invasion exceeding 6 mm, perineural invasion, and extension into adjacent muscle (pT3N0). Although surgical margins were negative, pulmonary metastases developed 12 months after surgery, followed by suspected pleural dissemination and spinal canal extension. The patient declined further aggressive treatment and died of the disease 48 months after surgery. Conclusion:This case highlights the importance of integrating clinical, radiological, and pathological findings for accurate diagnosis of salivary gland tumors, particularly when biopsy results are inconsistent with clinical suspicion.

ABSTRACT Black hairy tongue is a benign condition caused by elongation and defective desquamation of the filiform papillae, and it is uncommon in neonates and infants. We report a case in a 54‐day‐old girl who presented with a black lesion on the tongue dorsum. The lesion had first been noted at the 1‐month medical checkup and persisted despite observation. At presentation, a localized blackish‐brown lesion with accentuated filiform papillae was observed on the tongue dorsum and could not be wiped off with gauze. Oral candidiasis was considered in the differential diagnosis, but microbiological examination detected no Candida species. A clinical diagnosis of black hairy tongue was made, and the parents were instructed to gently clean the tongue dorsum with gauze and a sponge brush. The lesion resolved within 2 weeks without recurrence. Recognition of this benign entity may help avoid unnecessary treatment in infants.

The infraorbital nerve (ION), a branch of the maxillary division of the trigeminal nerve, provides sensory innervation to the midface via its terminal divisions. Among these, the superior labial branch (SLb) supplies the upper lip and adjacent mucosa, regions frequently involved in oral, maxillofacial, and cosmetic procedures. Despite its clinical importance, the anatomy of the SLb has received relatively limited attention compared with other ION branches. This review synthesizes current evidence on the SLb's course, branching patterns, innervation, morphometry, and variations, with emphasis on its relevance to surgical practice. Anatomical studies demonstrate that the SLb is the largest terminal division of the ION, often exhibiting medial and lateral subdivisions that anastomose with neighboring nerves. Its distribution predominantly follows a vertical orientation, supplying both cutaneous and mucosal structures of the upper lip. Variability in origin, branching, and accessory foramina underscores the need for careful surgical planning. Injury to the SLb is a recognized complication of Le Fort I osteotomy, midfacial trauma, and periapical procedures, potentially leading to long-term sensory disturbances. A comprehensive understanding of the SLb enhances intraoperative nerve preservation and may reduce postoperative morbidity, highlighting its significance for clinicians operating in the midfacial region.

The Japanese Society of Oral Oncology developed these clinical practice guidelines to establish standard procedures, enhance safety, and promote understanding of Alluminox treatment (photoimmunotherapy) for oral cancer. Formulated by a dedicated working group through a comprehensive literature search of clinical studies via PubMed and Ichushi-Web (a Japanese biomedical database), the guidelines cover essential perioperative management and site-specific protocols. Alluminox treatment is a localized therapy combining an antibody–photosensitizer conjugate and a laser system to selectively destroy EGFR-expressing cancer cells, and is indicated for unresectable locally advanced or locally recurrent head and neck cancers. Successful management requires a strict light-shielding environment for a specified period post-administration to prevent photosensitivity. Furthermore, because the treatment induces significant local tissue destruction, mandatory hospitalization under general anesthesia is necessary to manage acute, severe pain and closely monitor the airway due to the risk of post-irradiation laryngeal edema. Detailed specific sub-guidelines are provided for distinct anatomical sites, including the tongue, floor of the mouth, buccal mucosa, gingiva, palate, lips, and cervical lymph nodes. These site-specific protocols address technical challenges such as utilizing surgical navigation systems, managing tumor-necrosis-induced tissue defects or fistulas, and managing the risks of massive hemorrhage, while establishing tumor invasion into major vessels like the carotid artery as a strict contraindication. Ultimately, these guidelines serve as a foundational reference to optimize therapeutic safety and efficacy in oral oncology. This article is an English translated version based on the original clinical practice guidelines published by the Japanese Society of Oral Oncology in 2025.

Septic arthritis of the temporomandibular joint (SATMJ) is a rare but potentially serious condition, and standardized diagnostic and therapeutic strategies have not been established. We present the case of a 70-year-old man who developed acute right temporomandibular joint (TMJ) pain, swelling, mandibular deviation, and inability to achieve mouth closure. Computed tomography and magnetic resonance imaging revealed right TMJ dislocation, joint effusion, degenerative changes, and anterior disc displacement with effusion. Aspiration of the joint yielded neutrophil-predominant purulent fluid, although bacterial cultures were negative. The patient was treated empirically with intravenous ceftriaxone followed by oral clindamycin and amoxicillin, resulting in rapid symptom resolution, and the dislocation spontaneously reduced without surgical intervention. No recurrence was observed during three months of follow-up. This case highlights the diagnostic challenges associated with culture-negative SATMJ, supports the role of early empirical antibiotic therapy, and suggests that chronic joint instability due to habitual dislocation may predispose the TMJ to infection.

ABSTRACT Introduction Although mandibular odontogenic deep neck infections are occasionally fatal, the transmission pathway has not been elucidated. Materials and Methods This multicenter retrospective study was comprised of the patients of both sexes who were over 18 years of age and who had mandibular odontogenic deep neck abscesses. The patients' characteristics, laboratory tests, and radiographic findings were analyzed. Results One hundred eighteen patients with mandibular odontogenic deep neck abscesses were included. Bone resorption superior to the mylohyoid line and the related abscess formation in submandibular space or submental space were both significantly associated with the presence of sublingual space abscess. In addition, the type of causative tooth was not a risk factor for abscess formation in both the sublingual space and “submandibular or submental” space. Conclusions When an odontogenic lesion is located superior to the mylohyoid line, the abscess tends to initially form in the sublingual space and subsequently spread to the submandibular or submental space. Since any mandibular tooth can lead to abscess formation in these regions, oral and maxillofacial surgeons should carefully assess the anatomical position of the lesion and accurately identify the causative tooth.

BACKGROUND:Deep neck infections (DNIs) are potentially life-threatening diseases that are mainly caused by odontogenic and peritonsillar infections. Although DNI has also been reported to be caused by foreign bodies, no review articles exist to date. METHODS:A comprehensive literature search was conducted using PubMed for articles published between 2005 and 2025. RESULTS:A total of 131 relevant articles were identified. Frequently reported foreign bodies included injectable materials used in facial filler and fish bone. The latency to symptom onset varied widely, ranging from within 1 h after foreign body insertion to as long as 25 years, with substantial differences observed depending on the type of foreign body. CONCLUSION:Although foreign bodies are rare causes of DNIs, various type of foreign bodies have been reported. Recognizing the possibilities of DNIs caused by foreign bodies will help oral and maxillofacial surgeons to search for the cause rapidly and determine treatment plans and prevent recurrence.

Sarcopenia is increasingly recognized as a key predictor of adverse health outcomes. This study aimed to evaluate the impact of computed tomography-assessed sarcopenia (CT–SP) on the clinical severity and hospitalization duration of odontogenic deep neck infections (DNIs). Total of 119 patients admitted for odontogenic DNI treatment were included. Patients were divided into two groups by DNI clinical severity (severe or mild) and the patients' characteristics, including CT–SP based on skeletal muscle index (SMI), were compared between two groups. Multivariable logistic regression analysis was performed to identify independent risk factors for severe DNI. The correlation between SMI and hospitalization duration was assessed using Spearman’s rank correlation coefficient. Of the 119 patients, 60 (50.4

BACKGROUND/AIM:Bone destruction caused by oral cancer severely impacts patient quality of life. This study aimed to clarify the role of angiogenin (ANG) in osteoclastogenesis and oral cancer-induced bone destruction. MATERIALS AND METHODS:Recombinant ANG was used to assess its effects on osteoclast formation and bone resorption activity in bone marrow cultures. ANG-knockdown oral squamous carcinoma HSC-2 cells (ANG-RNAi) were transplanted into intramedullary cavities of femurs. Bone destruction was radiologically analyzed, while angiogenesis and osteoclast induction in the surrounding area of the transplanted lesion were histologically examined. RESULTS:Recombinant ANG promoted osteoclast formation and bone resorption activity. Transplantation of ANG-RNAi cells significantly reduced tumor growth and bone destruction properties compared to transplantation of control cells. Histological analysis revealed lower angiogenesis and fewer osteoclast induction in the ANG-RNAi cells-transplanted group. CONCLUSION:ANG mediates oral cancer-induced bone destruction by promoting osteoclast formation and resorption. These findings suggest that ANG could be a potential therapeutic target for suppressing tumor growth, angiogenesis, and bone destruction in oral cancer therapy.