Clinical Application of the IllumiScan Fluorescence Visualization Device in Detecting Oral Mucosal Lesions.

OBJECTIVE: Fluorescence visualization devices are screening devices that can be used to examine lesions of the oral mucosa non-invasively. We observed oral squamous cell carcinoma (OSCC) and leukoplakia using the IllumiScan (Shofu, Kyoto, Japan) fluorescence visualization device and examined its usefulness and characteristics. METHODS: We investigated 31 OSCC and nine leukoplakia in patients who were examined using the IllumiScan and treated in our department from January 2017 to February 2018. Images taken with the IllumiScan were analyzed using image analysis software. We also examined the lesions using narrowband imaging (NBI). Additionally, the IllumiScan and NBI images and the non-stained areas of iodine staining method (IOM) were visually evaluated. RESULTS: The average luminance of OSCC in the keratinized mucosa was significantly lower than that of OSCC in non-keratinized mucosa. The average luminance of OSCC was significantly lower than that of leukoplakia. Even in keratinized mucosa where IOM is impossible to use, the OSCC lesion exhibited fluorescence visualization loss. CONCLUSION: The application of the fluorescence visualization device to the oral mucosa may be useful for distinguishing between cancer and normal areas and can be used to detect OSCC in the keratinized mucosa. The use of the IllumiScan in combination with other conventional screening methods may lead to a better diagnosis.

The Usefulness of Piezoelectric Surgery in Sagittal Split Ramus Osteotomy.

Mandibular osteotomy carries with it a risk of damaging blood vessels and nerves when using traditional surgical techniques. Piezosurgery®, is a new technique that uses ultrasonic vibration to enable bone-selective sectioning without damage to the surrounding soft tissues. However, paralysis may not be completely eliminated using Piezosurgery® for osteotomy. We investigated how piezoelectric surgery in bilateral sagittal splitting ramus osteotomy (BSSRO) affected the surrounding soft tissue. Forty-four patients with skeletal mandibular prognathism underwent mandibular setback with BSSRO. Patients were divided into two groups, those treated by the conventional chisel technique and those treated by Piezosurgery®. Osteotomy time, blood loss, and incidence of paresthesia were compared retrospectively. Osteotomy time and blood loss in the piezo group were significantly reduced compared to the chisel group. Interestingly, whereas paresthesia incidence immediately after the operation did not differ between the groups, paresthesia in the piezo group 3 months postoperatively was significantly less than in the chisel group. However, a few cases of paralysis did not recover even in the piezo group. Blood loss and osteotomy time did not correlate with the paralysis. This study demonstrates that while piezoelectric surgery does impact the nerve tissue, the use of piezoelectric surgery in BSSRO leads to significantly less long term paralysis compared to surgery done by chisel.

Parotid Branches of the Auriculotemporal Nerve: An Anatomical Study With Implications for Frey Syndrome.

The auriculotemporal nerve is one of the many branches of the mandibular division of the trigeminal nerve. Of these, its superficial temporal branch has been most described. Although the parotid branches, secretomotor fibers to the parotid gland, are well known as the cause of Frey syndrome, there have been almost no descriptions of their anatomy. In this study, the authors dissected the parotid branches of the auriculotemporal nerve to elucidate their anatomy. A total of 10 sides from 7 adult and embalmed cadaver heads were used in this study. The specimens were derived from 3 males and 4 females, the age of cadavers at death ranged from 65 to 92 years old. Measurements included their diameter and the distance of their branching point from the main trunk of the auriculotemporal nerve from the middle of the tragus. Three of 10 sides had 2 parotid branches and 7 sides were found to have 1 parotid branch. The vertical distance between middle of the tragus to branching point of the parotid branch ranged from 1.79 to 16.17 mm. The horizontal distance between middle of the tragus to branching point of the parotid branch ranged from 3.03 to 12.62 mm. The diameter of the parotid branch ranged from 0.31 to 0.49 mm. An improved knowledge of the parotid branch of the auriculotemporal nerve might decrease injury to these structures with the potential for postoperative.

Bone marrow stromal cells can cause subcutaneous fibroblasts to differentiate into osteocytes in a physically stable spatial microenvironment in rats.

In this study, we investigated how rat bone marrow stromal cells (BMSCs) under a physically stable microenvironment influenced the subcutaneous fibroblasts. The model for this study involved setting up a space made up of a titanium mesh cage inserted into the subcutaneous region in rats and filled with a collagen matrix seeded with (1) BMSCs, (2) fibroblasts or (3) a combination of BMSCs and fibroblasts. Fibroblasts for transplantations were taken from enhanced green fluorescence protein (EGFP) transgenic "green rats" which enabled us to trace the fate of the cells in vivo. A series of X-ray computed tomographic (CT) images were taken of each implant over a period of 8 weeks, and the implants were then removed and examined histologically. As a result, while generated bone was observed in each case that included BMSCs (the BMSCs and combination group), there was no generated bone observed in the group using fibroblasts only. Interestingly, EGFP-positive osteocytes were observed in the generated bone of the combination group, indicating that the transplanted fibroblasts differentiated into osteocytes during the bone formation. Thus, we demonstrated that genuine intrinsic fibroblasts are able to become osteocytes as a result of the influence of BMSCs.

The effect of the microenvironment created by a titanium mesh cage on subcutaneous experimental bone formation and inhibition of absorption.

We attempted to form ectopic bone under the skin of rats without adding any extrinsic bone-inducing growth factors or cytokines using bone marrow stromal cells (BMSCs), a collagen scaffold and a titanium mesh cage. We set up a space made up of a cage inserted into the subcutaneous region of rats' backs, where we could eliminate the possible influence of residual bone tissue on bone induction. We filled this space with a collagen matrix containing BMSCs. At week 8 and month 6 after implantation, the specimens were removed and observed histologically, histochemically and enzyme histochemically. As a result, bone tissue was identified in each case within the titanium cages, even though we had not used bone-inducing chemical substances. Bone generation was not found in test cases without a cage. Enhanced green fluorescence protein (EGFP) labeling of the implanted BMSCs clearly showed that these cells differentiated into osteoblasts and subsequently into osteocytes in the formed bone tissue. Host cells without EGFP labeling were also confirmed to be involved in bone formation. Six months after transplantation, the implanted cells were still present in the generated bone, and no significant resorption of the generated bone was observed. These results indicate that the physically stable spatial microenvironment created by the cage in vivo plays an important role in bone formation and inhibition of its resorption, which we refer to as the 'cage effect'.

Pravastatin inhibits advanced glycation end products (AGEs)-induced proximal tubular cell apoptosis and injury by reducing receptor for AGEs (RAGE) level.

Advanced glycation end products (AGEs) and their receptor (RAGE) axis play a role in diabetic nephropathy. Statins have been shown to ameliorate renal function and reduce proteinuria in patients with chronic kidney disease. However, the effects of statin on AGEs-induced tubular cell damage remain unknown. We examined here whether and how pravastatin could block the AGEs-RAGE-elicited tubular cell injury in vitro. Gene expression level was evaluated by real-time reverse-transcription polymerase chain reactions. Reactive oxygen species (ROS) generation was measured with dihydroethidium staining. Apoptosis was analyzed in an enzyme-linked immunosorbent assay. Asymmetric dimethylarginine (ADMA) expression was evaluated by immunostaining. Pravastatin dose-dependently inhibited the AGEs-induced up-regulation of RAGE mRNA level, ROS generation and apoptosis in human renal proximal tubular cells. Further, AGEs decreased mRNA level of dimethylarginine dimethylaminohydrolase-2, an enzyme that mainly degrades asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase and subsequently increased ADMA generation in tubular cells, both of which were also prevented by pravastatin. Geranylgeranyl pyrophosphate (GGPP) treatment blocked all of the effects of pravastatin on tubular cells. We found that rosuvastatin also significantly blocked the AGEs-induced increase in RAGE mRNA level and ROS generation, both of which were prevented by GGPP. Our present study suggests that pravastatin could inhibit the AGEs-induced apoptosis and ADMA generation in tubular cells by suppressing RAGE expression probably via inhibition of GGPP synthesis. Pravastatin may exert beneficial effects on tubular damage in diabetic nephropathy by blocking the AGEs-RAGE axis.

Primary gingival angiosarcoma successfully treated by radiotherapy with concurrent intra-arterial chemotherapy.

The occurrence of angiosarcoma in the oral cavity is extremely rare, and optimal management of this tumor is undefined. These tumors are aggressive, with a high propensity for local recurrence. We present here a case of primary gingival angiosarcoma successfully treated by intra-arterial chemotherapy concurrent with radiation therapy. A 69-year-old female with a primary angiosarcoma in the right maxillary gingiva was admitted to our hospital. The diagnosis of angiosarcoma was established by immunohistochemistry. The patient refused surgical treatment, and so intra-arterial cisplatin and concurrent radiation were given. The gingival tumor disappeared after completion of the therapeutic regimen. However, the patient died 8 months after initial treatment because of multiple lung metastases. Locoregional control was achieved up to her death. To our knowledge, this is the first report of this treatment for angiosarcoma of the oral cavity.