Nobuo Takano

Detecting early oral cancer: narrowband imaging system observation of the oral mucosa microvasculature

The aim of this study was to analyze and describe the intrapapillary capillary loops (IPCL), which are a feature of early oral neoplastic lesions, using a narrowband imaging (NBI) system. Forty-one patients (26 men, 15 women; mean age, 52.34 years; range, 23-83 years) presenting with non-neoplastic or neoplastic lesions, and normal cases, were examined using the prototype Evis Lucera Spectrum (Olympus Co.). The images were analyzed and an IPCL classification was devised. All normal cases (n=10) had regularly distributed capillary loops of the same shape (type I). Non-neoplastic lesions (n=8) had mild changes of the capillary loops (types II and III) and neoplastic lesions (n=23) were irregularly distributed and had several loop shapes (types III and IV). The microvascular organization of non-neoplastic lesions was notably different from that of neoplastic lesions. A brownish area was found in five cases of early carcinoma. The narrowband imaging system is a potential approach for clinically analyzing microvascular organization and IPCL. It could be useful for diagnosing oral squamous cell carcinoma at an earlier stage and for determining the margin of resection.

Merkel cell carcinoma of palatal mucosa in a young adult: Immunohistochemical and ultrastructural features

The first case report of a merkel cell carcinoma arising from the palatal mucosa in a young adult is presented. The histopathological similarities of this tumour in skin and oral mucosa are also discussed. The patient was a 14-year-old female with a non-symptomatic painful swelling in the left molar region of the maxilla. Under the diagnosis of a malignant tumour, a partial maxillary resection was performed, but there was a recurrence, and finally the patient died of cerebral metastasis. The tumor was composed mainly of uniform small cells. Immunohistologically, a large number of the cells were reactive to neuron specific enolase (NSE) and cytokeratin CK19, and some of the cells were positive to CK8, CK13, CK20, PGP9.5 and CEA focally and slightly. Pseudo-rosette formation and squamous differentiation were frequently detected. The ultrastructure of the tumour cells showed abundant Golgi bodies associated with neurosecretory granules. We conclude that it is the first case of a Merkel cell tumour arising from palatal mucosa and invading underlying bone with reactive hyperplasia. These findings closely resemble those of the same tumour occurring in the skin

Nodular fascitis of the mandible in a child.

Nodular fascitis is an unusual, tumor-like, proliferative, fibroblastic lesion with infiltrative properties. We describe a case of nodular fascitis appearing in the mandible of a 2-year-old boy. A brief review of the literature on this lesion arising from intra or perioral regions, and the importance of differential diagnosis for this lesions are discussed.

Antimicrobial Susceptibility of Microorganisms Isolated from Periapical Periodontitis Lesions.

Periapical periodontitis usually results from microbial infection, with these microorganisms occasionally migrating to the root canal, which can lead to further, potentially life-threatening, complications. Here, the susceptibility of 27 bacterial strains to various antimicrobial agents was evaluated. These strains comprised 13 species; 16 of the strains were clinical isolates from periapical lesions. Each strain was inoculated onto blood agar plates containing one of the antimicrobial agents. The plates were incubated anaerobically at 37°C for 96 hr and the minimal inhibitory concentrations (MICs) determined. Ten strains required an MIC of 32 μg/ml or greater for amoxicillin, 6 for cefmetazole, and 5 for cefcapene among β-lactam antibiotics; 8 strains required an MIC of 32 μg/ml or greater for clindamycin, 4 for azithromycin, and 11 for clarithromycin among macrolide antibiotics; 3 strains required an MIC of 32 μg/ml or greater for ciprofloxacin and 2 for ofloxacin among fluoroquinolones. The effect of cefcapene on 5 strains was evaluated after biofilm formation to investigate the relationship between biofilm formation and susceptibility. All strains showed a decrease in susceptibility after biofilm formation. The results revealed that several antimicrobial agents commonly used in a clinical setting, including amoxicillin, cefmetazole, and clindamycin, are potentially effective in the treatment of orofacial odontogenic infections. The development of resistant strains, however, means that this can no longer be guaranteed. In addition, azithromycin, ciprofloxacin, and ofloxacin were more effective than the 3 β-lactam antibiotics tested. These results suggest that sensitivity testing is needed if odontogenic infections are to be treated safely and effectively.

Case of Suspected Sialodochitis Fibrinosa (Kussmaul’s Disease)

Here we report a case of Kussmauls disease, or sialodochitis fibrinosa. This rare disease is characterized by recurrent swelling of the salivary glands, which then discharge clots of fibrin into the oral cavity. An 80-year-old man with a history of allergic rhinitis visited our department with the chief complaint of pain in the bilateral parotid gland area on eating. An initial examination revealed mild swelling and tenderness in this region, and indurations could be felt around the bilateral parotid papillae. Pressure on the parotid glands induced discharge of gelatinous plugs from the parotid papillae. No pus was discharged, and there were no palpable hard objects. Panoramic X-ray showed no obvious focus of dental infection, and there was no calcification in the parotid gland region. Magnetic resonance imaging revealed segmental dilatation of the main ducts of both parotid ducts, with no signs of displacement due to sialoliths or tumors, or of abnormal saliva leakage. Two courses of antibiotic therapy resulted in no improvement. During treatment, gelatinous plugs (fibrin clots) obstructing the left parotid duct were dislodged by massage, which prevented further blockage by encouraging salivary outflow. The obstruction persisted in the right parotid duct, however. Therefore, the distal portion of the right parotid duct was partially resected and the opening into the mouth enlarged, which, in combination with massage, prevented further obstruction. The pain and swelling of the parotid gland and discharge of gelatinous plugs improved, with no further recurrence at 12 months postoperatively. This case is presented along with a review of the relevant literature.

Incidence and risk factors for colorectal neoplasia in patients with oral squamous cell carcinoma

Colorectal adenoma and cancer are not regarded as being associated with primary oral cancer. The aim of this study was to determine whether screening colonoscopy should be performed for patients with oral cancer in addition to the upper gastrointestinal endoscopic screening that is now routinely performed.

Morphologic Evaluation for Safe Le Fort I Osteotomy in Cleft Lip and Palate

Objective: The present study aimed to determine the structure and morphology of the maxilla in patients with cleft lip and palate to ensure safe Le Fort I osteotomy. Patients: A total of 34 sides of 17 patients with unilateral cleft lip and palate (nonsyndromic cases) were included in this study. The control group included 10 sides of 5 patients who exhibited skeletal mandibular protrusion without malformation. Methods: Finite element analysis was performed to examine the distribution of occlusal force over the maxilla, and continuous 3-dimensional measurement was performed at the sites of stress concentration. Results: In patients with cleft lip and palate, bones at the lateral border of the piriform aperture and the anterior wall of the maxillary sinus were significantly thicker than those in controls (P < .05). Furthermore, the attachment of the pterygomaxillary junction was wider and thicker (P < .05), and the anterior distance to the descending palatine artery was shorter (P < .01) in patients with cleft lip and palate than in controls. Our results further indicated that alveolar bone grafting may significantly influence bone thickness and the attachment state of the pterygomaxillary junction. Conclusions: Our results suggest that the complications of LFI can be reduced in patients with cleft lip and palate by ensuring proper understanding of each patient’s maxillary anatomy and bone thickness, as well as the location of the descending palatine artery and the attachment state of the pterygomaxillary junction.

Verruciform Xanthoma with Equivocal Exfoliative Cytological Diagnosis

Verruciform xanthoma (VX), a papillary or wart-like lesion of the mucosa, is histopathologically characterized by papillary projection of the epithelium and an aggregation of foam cells in the lamina propria. Here, we describe a case of VX in the posterior mandibular gingiva, initially suspected to be a benign lesion based on clinical findings and cytology prior to an excisional biopsy. The patient was a 62-year-old man who had visited a local dentist approximately 1 year earlier, presenting with a white lesion in the left posterior mandibular gingiva that resisted removal by scraping. The lesion was left untreated as there were no subjective symptoms. Thereafter, the surface of the lesion roughened and the patient was referred to our department for a comprehensive examination. A circumscribed, granular mass, 15-mm in diameter, with a red and white surface was observed in the left posterior mandibular buccal gingiva. Exfoliative cytology was performed. The diagnosis was a class III lesion. Excisional biopsy was performed under local anesthesia. Histopathological examination led to a diagnosis of VX. At 1 year postoperatively, the patient is making satisfactory progress without recurrence. Verruciform xanthoma is difficult to diagnose preoperatively, and is commonly resected under a clinical diagnosis of papilloma or benign tumor. A benign lesion was also initially suspected in the present case and cytological analysis performed to confirm absence of malignancy. The lesion could not be diagnosed as VX preoperatively. Verruciform xanthoma can be over-diagnosed based solely on cytological examination because it often involves cellular atypia reflecting its characteristic extension of rete pegs and keratinization of surface cells, indicating the need for care in arriving at a definitive diagnosis.

Three-dimensional Finite Element Analysis of Bone Fixation in Bilateral Sagittal Split Ramus Osteotomy Using Individual Models

The purpose of this study was to investigate factors involved in stress on locking mini-plate/screws used in orthognathic surgery based on patient-specific 3-dimensional finite element analysis. Data were obtained from 10 patients undergoing mandibular advancement by bilateral sagittal split ramus osteotomy. All underwent osteosynthesis with 2.0-mm titanium locking mini-plate/screws. A 3-dimensional finite element model of the mandible was created for each patient and each model subjected to the same loading conditions, which produced different stress values on locking mini-plate/screws. When the contact area of the proximal and distal bone segments was narrower and bone mineral density (BMD) lower, the von Mises stress values on the plate/screws were higher (contact area, p<0.01; BMD, p<0.05). The present results suggest that bone contact area and BMD should be considered as plate stress factors.

Squamous Cell Carcinoma of Maxillary Gingiva Progressing to Disseminated Carcinomatosis of Bone Marrow

Disseminated carcinomatosis of the bone marrow (DCBM) is characterized by diffuse metastasis to bone marrow and sudden mortality. To the best of our knowledge, no studies to date have reported progression of oral squamous cell carcinoma to DCBM. Herein, we report a case of squamous cell carcinoma in the maxillary gingiva suspected of progressing to DCBM. A 64-year-old woman presented with white lesions on the left maxillary gingiva. The lesions were diagnosed as squamous cell carcinoma (T2, N0, M0), and partial maxillectomy performed. Two years and 5 months after surgery, metastasis was noted in the left cervical lymph node and left radical neck dissection carried out. The subsequent diagnosis was right cervical lymph node metastasis and multiple bone metastases. The patient also presented with thrombocytopenia, anemia, and elevated levels of alkaline phosphatase, probably due to metastatic bone disease. Although various antitumor therapies were administered, the patient died 6 months after diagnosis of multiple bone metastases.