Correlation between the malignancy and prognosis of oral squamous cell carcinoma in the maximum standardized uptake value.

Positron emission tomography/computed tomography (PET/CT) examinations are indispensable in determining the stage, evaluating the treatment response, and diagnosing recurrence and metastasis during oral cancer treatment. In this study, we examined the correlation between the maximum standardized uptake value (SUVmax) for 18F-FDG PET/CT and the progressive factors, biological characteristics, and prognosis of oral cancer. We included 52 cases of oral squamous cell carcinoma with surgery as the initial treatment. Inclusion criteria included tumor diameter of ≥ 1 cm excluding superficial cancer. We performed 18F-FDG PET/CT examinations before surgery and determined the correlation between SUVmax and clinicopathological factors, such as histological grade, Ki-67 expression, as well as progress factors. SUVmax was significantly correlated with clinical T stage, vascular invasion, lymphatic invasion, Ki-67 expression, and postoperative event (recurrence or metastasis) in Student's t test. Using a cut-off SUVmax of 8.0, clinical T stage, lymph node metastasis, vascular invasion, infiltrative pattern, and Ki-67 expression significantly correlated in chi-squared test. Although observed and expected 3-year overall survival rates were not significantly different, observed and expected 3-year disease-free survival rates were significantly different. Analyzing each clinicopathological factor using various data obtained from 18F-FDG PET/CT scans may be useful to determine prognosis during oral cancer treatment.

Follicular lymphoid hyperplasia of the posterior maxillary site presenting as uncommon entity: a case report and review of the literature.

BACKGROUND: Follicular lymphoid hyperplasia (FLH) is characterized by an increased number and size of lymphoid follicles. In some cases, the etiology of FLH is unclear. FLH in the oral and maxillofacial region is an uncommon benign entity which may resemble malignant lymphoma clinically and histologically. CASE PRESENTATION: We report the case of a 51-year-old woman who presented with an asymptomatic firm mass in the left posterior maxillary site. Computed tomography scan of her head and neck showed a clear circumscribed solid mass measuring 28 × 23 mm in size. There was no evidence of bone involvement. Incisional biopsy demonstrated benign lymphoid tissue. The patient underwent complete surgical resection. Histologically, the resected specimen showed scattered lymphoid follicles with germinal centers and predominant small lymphocytes in the interfollicular areas. Immunohistochemically, the lymphoid follicles were positive for CD20, CD79a, CD10, CD21, and Bcl6. The germinal centers were negative for Bcl2. Based on these findings, a diagnosis of benign FLH was made. There was no recurrence at 1 year postoperatively. CONCLUSIONS: We diagnosed an extremely rare case of FLH arising from an unusual site and whose onset of entity is unknown. Careful clinical and histopathological evaluations are essential in making a differential diagnosis from a neoplastic lymphoid proliferation with a nodular growth pattern.

Toll-like receptor 2 activation implicated in oral squamous cell carcinoma development.

Recent studies have revealed that Toll-like receptors (TLRs) are highly expressed and activated in many types of cancer. Physiologically, TLR2 recognizes bacteria and other microorganisms in the oral cavity; however, the role of TLR2 in oral squamous cell carcinoma (OSCC) is unclear. In this study, we demonstrated that TLR2 is highly expressed in OSCC in comparison with adjacent non-malignant tissue. TLR2 was also expressed in OSCC-derived cell lines, and its expression was activated by ligands derived from bacteria and mycoplasma. Furthermore, to elucidate the mechanism of OSCC progression via TLR2 signal transduction, we focused on microRNAs (miRNAs) that are induced by TLR2 activation. Interestingly, ligand activation of TLR2 induced the expression of miR-146a and we found that downregulation of caspase recruitment domain-containing protein 10 (CARD10) mRNA in OSCC-derived cell lines. Moreover, knockdown of CARD10 induced resistance to cisplatin-induced apoptosis in OSCC cells. These findings suggest that the activation of TLR2 by bacterial components can enhance the progression of OSCC and may be implicated in acquired resistance to cisplatin-induced apoptosis through regulation of the miR-146a pathway.

Evaluation of OK-432 Injection Therapy as Possible Primary Treatment of Intraoral Ranula.

PURPOSE: A ranula is a pseudocyst caused by mucous extravasation from the sublingual gland. Recently, a sclerosing agent, OK-432 (picibanil), has been reported to be highly effective for treating lymphangioma and cervical cystic lesions. The present study assessed the effectiveness of OK-432 injection therapy for intraoral ranula to clarify whether it can be used as the primary treatment. PATIENTS AND METHODS: The present study was a retrospective clinical study of patients with intraoral ranula who received OK-432 injection therapy from 2005 to 2015. The ranula size was measured on computed tomography or magnetic resonance imaging studies. We dissolved 1 Klinische Einheit (KE) unit of OK-432 powder in normal saline equal to the aspiration volume. The primary endpoint was the treatment results. The secondary endpoints were the relation between the treatment results and the lesion length and aspiration volume. RESULTS: A total of 23 patients received OK-432 injection therapy for an intraoral ranula. The mean lesion size was 19.96 mm. The mean aspiration volume was 2.14 mL. The number of injections was 1 to 4 (mean 1.70). The treatment results were complete regression (CR) in 18 (78.2%), partial regression (PR) in 3 (13.0%), and no response (NR) in 2 (8%) patients after the last injection. The overall efficacy rate was 91.2% (21 of 23). No serious complications were observed. The lesion length and aspiration volume of the CR group was 17.38 mm and 1.40 mL, respectively. The lesion length and aspiration volume of the PR/NR group was 29.20 mm and 4.80 mL, respectively. The PR/NR group lesions were significantly larger than the CR group lesions. CONCLUSIONS: OK-432 injection therapy for intraoral ranula is safe and effective compared with other surgical therapies. This therapy could potentially become a primary treatment of intraoral ranula.

Indications of Potassium Titanyl Phosphate Laser Therapy for Slow-Flow Vascular Malformations in Oral Region.

BACKGROUND: Indications for laser therapy for slow-flow vascular malformations in the oral and maxillofacial regions have not been clearly documented. The authors aimed to estimate the frequency of resolution of slow-flow vascular malformations and to identify risk and prognostic factors associated with resolution in potassium titanyl phosphate (KTP) laser treatment. METHODS: This study was designed as a prospective cohort study. Patients who had diagnosed slow-flow vascular malformations were continuously assigned to receive KTP laser therapy. All patients had intralesional laser photocoagulation performed under local anesthesia. Administered power of the KTP laser was fixed at 2 watts throughout the procedure in all patients. The primary endpoint was to understand the frequency of resolution of slow-flow vascular malformations in KTP laser treatment. Secondary endpoints were: treatment outcomes based on lesion size; treatment outcomes based on location; treatment outcomes based on total energy in joules; types of complications. Treatment outcomes were judged by a clinical assessment as well as reduction in lesion size on magnetic resonance imaging. RESULTS: Data were obtained from 26 patients (9 men, 17 women) with 38 lesions. The average lesion size was 13.5 ±â€Š7.7 mm. Treatment outcomes based on lesion size showed that cure and regression were obtained in lesions less than 30 mm in size. However, lesions larger than 30 mm showed no response. Lesions in the tongue and lips showed higher cure rates than in other areas. Treatment outcomes based on administered total energy in joules showed that 68% of lesions were treated and responded well at less than 400 joules. Complication rate was relatively high in the buccal mucosal lesions. Immediate postoperative complications such as necrosis were more common in high-energy administration than in low-energy administration. CONCLUSION: Our results indicated that KTP laser therapy was effective for slow-flow vascular malformations less than 30 mm in size without significant side effects.

Adenosquamous carcinoma of the tongue: clinicopathologic study and review of the literature.

Adenosquamous carcinoma (ASC) of the tongue is an uncommon malignant oral neoplasm with mixed glandular and squamous differentiation and a propensity for aggressive clinical behavior. Here, we report a rare case of ASC of the lateral border of the tongue in a 65-year-old Japanese man. The patient was treated by radical operation and remained well for 6 months before developing metastasis of the hilar and pretracheal lymph nodes. Subsequently, the patient was treated with combined chemotherapy (nedaplatin plus docetaxel and S-1 for two cycles, intravenously) and radiotherapy. Radiation therapy of metastatic lymph nodes was performed at a total dose of 60 Gy and was delivered in 2 Gy fractions 5 days/week. The patient is currently tumor free and is being followed up carefully. This article describes a rare case of ASC of the tongue and its conventional histologic, immunohistochemical, and electron microscopic findings, together with a review of the literature. The findings provide important information to better understand the possible clinical and therapeutic approaches for this uncommon tumor of the tongue.

Nerve Sharing Between the Lingual and Mental Nerve to Restore Lower Lip Sensation After Segmental Resection of the Mandible.

This report demonstrates a successful new procedure for reconstructing the inferior alveolar nerve by transplanting the great auricular nerve (GAN) between the mental nerve and the remaining submandibular ganglion to achieve nerve sharing of the lingual nerve. A 59-year-old woman with discomfort in the left mandibular retromolar region and ipsilateral neck was referred to our hospital by a local dentist. Physical examination showed mild swelling and redness at the left mandibular retromolar region. The histologic diagnosis showed central mucoepidermoid carcinoma of the jaw. With the patient under general anesthesia, segmental resection of the mandible followed by level 1 selective neck dissection was performed. The resected mandible was reconstructed with a titanium plate. The submandibular incision was extended to the lower edge of the tragus for harvesting of the GAN. The GAN was grafted, and an epineural neurorrhaphy was carried out with the mental nerve, as well as the submandibular ganglion, under a microscope. After the operation, submental sensation was evaluated with a Semmes-Weinstein pressure esthesiometer. The Semmes-Weinstein pressure esthesiometer test showed a loss of perception at the third week after surgery. Within 12 months, nerve sensation was substantially improved and the patient was free from discomfort.

Metastatic rectal adenocarcinoma in the mandibular gingiva: a case report.

BACKGROUND: Oral metastatic tumor from a rectal adenocarcinoma is very uncommon. The primary site is usually assumed based on the past clinical history. In the case of oral metastatic tumors, they commonly have a poor prognosis because often they have already spread to other sites. CASE PRESENTATION: We present the case of a 64-year-old male patient with secondary metastasis to the mandibular gingiva via lung metastasis after the surgical resection of a primary rectal adenocarcinoma. The gingival lesion grossly appeared as a swollen mass, making mastication difficult. The patient received palliative radiotherapy for the mandibular mass lesion. However, tumor reduction was accompanied by the development of pneumonia and deterioration of the patient's cachexia. Thus, the radiotherapy was discontinued but the patient died 2 months postradiotherapy. In the long term after its primary resection, the rectal adenocarcinoma was deduced to have finally metastasized to the oral region. CONCLUSIONS: In this case, we consider a distant secondary metastasis to the oral region from a rectal malignancy. In such cases, careful clinical and pathologic evaluations are necessary, with careful consideration of the inclusion of palliative treatment in the therapeutic management.

A randomized trial to identify the most effective dose of remifentanil during Le Fort I osteotomy.

PURPOSE: The Le Fort I osteotomy (L-I) requires extensive dissection and manipulation of tissue, causing hemodynamic instability and an undesirable postoperative stress response. This study aimed to clarify the most effective dose of remifentanil during L-I. MATERIALS AND METHODS: This study was designed as a prospective, randomized, controlled double-blinded study. Patients (American Society of Anesthesiologists physical status I to II) undergoing L-I were randomly assigned to receive anesthesia with propofol and remifentanil under 3 remifentanil dose conditions: 0.25 µg/kg/minute (group 1), 0.5 µg/kg/minute (group 2), and 0.75 µg/kg/minute (group 3). All patients underwent L-I with propofol and remifentanil target-controlled anesthesia. The study endpoints were mean arterial pressure (MAP) and heart rate. Data were recorded before L-I (20-minute period before surgery), during L-I (from the beginning of surgery to downfracture), and after L-I (20-minute period after downfracture). Average age, gender, average body mass index, aimed maxillary position, average bispectral index, average surgery time, and average blood loss also were examined. Data were analyzed using the Bartlett test and then 1-way analysis of variance with the Bonferroni multiple comparison test. RESULTS: Data were obtained from 20 patients (9 men, 11 women). The average operating times for groups 1, 2, and 3 were 53.1, 46.7, and 49 minutes, respectively. The age range was 18 to 46 years (average, 26.05 yr). The rate of MAP increase from before to during L-I in group 1 was 10.8% (n = 7). The rate of MAP increase from before to during L-I in group 3 was 2.1% (n = 6). Group 3 showed a significantly lower rate of MAP increase during and after L-I compared with group 1 (P < .05). CONCLUSION: Remifentanil administration at 0.75 µg/kg/minute stabilized hemodynamics during L-I without major side effects. Results indicated that the standard index of remifentanil administration during L-I should be 0.75 µg/kg/minute when using oxygen, propofol, and remifentanil for general anesthesia.

Exceptionally large solitary fibrous tumor arising from the cheek: an immunohistochemical and ultrastructural study with a review of the literature.

Solitary fibrous tumor (SFT) is a rare mass-forming soft tissue tumor that occurs most commonly in the pleura, but has been described in various extrathoracic sites. Extrapleural manifestation of SFT, particularly in the head and neck region, is rare. The most common extrapleural site is the oral cavity; these tumors have also been described in the orbit, nasopharynx, paranasal sinuses, salivary glands, and larynx. We report an extremely rare case of a SFT in the subcutaneous region of the cheek. This tumor in the left cheek was a large firm mass, approximately 8.5 cm × 6 cm in size and was successfully treated by surgical resection. Immunohistochemistry revealed reactivity for vimentin, CD34, and bcl-2, but no staining for cytokeratin, epithelial membrane antigen, S-100, desmin, caldesmon, actin, α-smooth muscle actin, CD117, and CD99. Immunohistochemical study is the key to establish a definitive diagnosis of SFT, and ultrastructural study is also useful for making an accurate diagnosis. The patient recovered uneventfully without evidence of tumor recurrence 2 years after surgery.

Solitary myofibroma of the mandible: an immunohistochemical and ultrastructural study with a review of the literature.

A solitary myofibroma (MF) is an unusual spindle cell neoplasm that usually arises in the soft tissue, skin, or bone of the head and neck region in infancy. We report an extremely rare case of MF of the mandible in an 18-year-old Japanese woman together with the conventional histologic, immunohistochemical, and electron microscopic findings. The tumor was well circumscribed and composed of fibroblast-like or myofibroblast-like spindle cells. On immunohistochemical evaluation the tumor cells were positive for vimentin, α-smooth muscle actin, HHF-35, and calponin, but negative for neurogenic antigens and markers for vascular endothelial cells. The Ki-67 labeling index was 10 % and the p53 labeling index was 10 %. Ultrastructural examination revealed smooth muscle cell differentiation. The patient was treated by surgical resection and underwent follow-up without any signs of recurrence. MF presents a wide range of differential diagnosis, including benign and malignant neoplasms. Therefore, accurate diagnosis may avoid an unnecessarily aggressive therapy.

Cyclo-oxygenase-2 expression is associated with vascular endothelial growth factor C expression and lymph node metastasis in oral squamous cell carcinoma.

PURPOSE: Cervical lymph node metastasis in oral squamous cell carcinoma (OSCC) is recognized as a poor prognostic factor, although its mechanism remains unclear. Recently, cyclo-oxygenase-2 (COX-2) level has been found to correlate highly with vascular endothelial growth factor C (VEGF-C) and lymph node metastasis, as in other solid tumors. However, there has been no report of this correlation in OSCC. Therefore, the aim of this study was to investigate whether COX-2 immunohistochemical expression in OSCC was associated with VEGF-C expression, histopathologic parameters, and lymph node metastasis. MATERIALS AND METHODS: Lymphatic vessel density, VEGF-C, and COX-2 immunohistochemical expression were examined pathologically in 60 specimens of invasive OSCC. Relations of histopathologic parameters to lymph node metastasis were analyzed. RESULTS: Expression levels of VEGF-C and COX-2 and lymphatic vessel density in the lymph node metastatic group were significantly higher than in the nonmetastatic group (P < .01). A significant correlation was found between the expression levels of VEGF-C and COX-2 (r = 0.512; P < .001). COX-2 expression was significantly related to lymph node metastasis (P = .004) and VEGF-C expression (P = .005). Univariate analysis showed that survival time was impaired by higher COX-2 and VEGF-C expression levels. Multivariate survival analysis showed that COX-2 expression was an independent prognostic factor. CONCLUSION: This study showed that VEGF-C expression was upregulated by COX-2 in OSCC. High VEGF-C expression appears to promote peritumoral lymphangiogenesis. These data indicated that lymph node metastasis is promoted by COX-2 and VEGF-C in OSCC.

In vitro and in vivo evaluation of surface functionalization of titanium with H2 O2 hydrothermal treatment and FGF-2.

The goals of the study were to investigate the effects on bone bioactivity of a titanium dioxide layer formed by hydrothermal oxidation of a titanium surface with hydrogen peroxide (H2 O2 ) and loading with fibroblast growth factor-2 (FGF-2) in vitro and in vivo. Ti-6Al-4V discs were hydrothermally oxidized with H2 O2 and then loaded with FGF-2. After cytotoxicity testing, Ti-6Al-4V mini-implants were subjected to the same treatment, and their osteogenic potential was evaluated histologically in a rat model. H2 O2 hydrothermal oxidation resulted in a dense porous network structure and hydrophilic changes, which improved retention of FGF-2. Morphologically, the cell density was higher, cell elongation was more pronounced, and the cell adhesion area was significantly higher in FGF-2-loaded cells than in those without FGF-2. In a cell proliferation assay using mouse osteoblast-like cells, absorbance tended to increase over time, especially in the FGF-2 group after 7 and 14 days, and in a bone differentiation assay based on ALP activity, there was a significant increase in the FGF-2 group after 14 days. In the rat model, H2 O2 hydrothermal oxidation and FGF-2 loading both resulted in more laminar bone tissue in the bone marrow around the mini-implant. These results suggest that titanium surface functionalization by H2 O2 hydrothermal oxidation and FGF-2 may promote initial cell adhesion, proliferation, and osteodifferentiation, and enhance bone bioactivity. These effects all contribute to early bonding of an implant with the surrounding bone.

Skin and Bone Regeneration of Solid Bone Marrow Aspirate Concentrate Versus Platelet-Rich Fibrin.

Solid bone marrow aspirate concentrate (sBMAC) is harvested from bone marrow aspirate without anticoagulants by a centrifugation protocol similar to that for platelet-rich fibrin (PRF) prepared from peripheral blood. It was hypothesized that sBMAC could accelerate not only wound healing but also bone regeneration because of the abundant growth factor (GF) releases from enriched bone marrow cells. The purpose of the present study was to investigate skin wound healing and bone regenerative potential of sBMAC compared with arterial blood-derived PRF (Ar-PRF) and venous blood-derived PRF (Ve-PRF) in a skin defect and calvarial bone defect model in rabbits. GF release assays revealed significantly higher release of transforming growth factor-ß (TGF-ß), alkaline phosphatase (ALP), and osteocalcin (OCN) from sBMAC compared with PRFs for 24 h. In the skin defect animal model, sBMAC and PRFs promoted wound bed angiogenesis and re-epithelization in skin defect sites with higher collagen 1 synthesis, cytokeratin AE1/AE3, vascular endothelial growth factor (VEGF) expressions on week 1. Furthermore, a calvarial defect assay revealed that sBMAC promoted new bone formation with a sufficient bone marrow structure similar to that of intact bone in the bone defects. Ar-PRF achieved the second highest bone closure and new bone volume but yielded new bone that was thinner than the intact bone. In conclusion, sBMAC treatment might be a good option instead of PRF as an adjuvant therapy for both skin and bone tissue regeneration therapies in certain clinical situations. Impact statement Solid bone marrow aspirate concentrate (sBMAC) is new type of clot material prepared from bone marrow aspirate. The present study for the first time showed that sBMAC significantly accelerated both skin wound healing and bone formation in the defects, compared with conventional platelet-rich fibrin in rabbit experiment models.

A Custom-Made Surgical Guide for Accurate Enucleation of Nasopalatine Duct Cysts: A Technical Note and Case Report.

Nasopalatine cysts are common nonodontogenic cysts that occur in the maxilla. During the nucleation of large cysts extending to the floor of the nasal cavity, care must be taken to avoid damage to the nasal mucosa. In the present report, an innovative custom-made surgical guide made by a Three-dimensional printer is introduced for accurate enucleation surgery. The patient's cone-beam computerized tomography and dental model scan data were obtained, and a tooth-supported type of surgical guide was designed containing a circular plate structure showing the size of the cystic region, an indicator that showed the position of the bottom of the cyst, and a sliding stopper that was used to accurately indicate the position of the deepest cyst wall. The surgical tool enabled us to indicate the accurate size, location of the cysts, and approach direction. Although effective and accurate navigation systems have become increasingly available, the cost-effective and accurate computer-aided design/computer-aided manufacturing surgical guide system introduced in the present report could support the safe enucleation of large nasopalatine duct cysts.

Regenerative Potential of Solid Bone Marrow Aspirate Concentrate Compared with Platelet-Rich Fibrin.

Platelet-rich fibrin (PRF) prepared from venous blood is used in the clinic to improve soft tissue wound healing. Nevertheless, arterial blood or bone marrow aspirate might also be a candidate for the source of PRF-like concentrates. The purpose of the present study was to investigate blood/bone marrow aspirate concentrates obtained from arterial blood, venous blood, and bone marrow aspirate to determine its respective regenerative potential in vitro. Arterial blood-derived PRF (Ar-PRF), venous blood-derived PRF (Ve-PRF), and solid-type bone marrow aspirate concentrate (sBMAC) were prepared from New Zealand white rabbits. Each clot was evaluated for its cytocompatibility and regenerative potential on primary rabbit gingival fibroblasts and osteoblasts. Both gingival fibroblasts and osteoblasts treated with each concentrate showed excellent viability. Interestingly, the sBMAC-treated cells demonstrated a significantly greater migratory potential than the other treatment groups. Furthermore, higher mRNA levels of transforming growth factor-beta, vascular endothelial growth factor, and collagen 1 (COL1) in gingival fibroblasts were observed in the sBMAC group compared with the Ar-PRF and Ve-PRF groups. Greater osteoblast differentiation potential, including higher osteocalcin (OCN) expression and mineralization potential, was found in osteoblasts treated with sBMAC. However, minor differences between the behaviors of cells treated with Ar-PRF and Ve-PRF were observed. In conclusion, sBMAC might be a new candidate for promoting wound healing and bone regeneration. Further preclinical and clinical experiments are necessary to prove the regenerative potential of sBMAC in the body. Impact Statement Blood concentrate material such as platelet-rich plasma or platelet-rich fibrin (PRF) is used in clinical practice to promote tissue regeneration in the field of dentistry, orthopedic surgery, and plastic surgery. The present study introduces a new type of solid bone marrow aspirate concentrate material and, for the first time, shows its excellent regenerative potential in both gingival fibroblasts and osteoblasts in vitro compared with that of conventional PRF.

Osteoclast behaviors on the surface of deproteinized bovine bone mineral and carbonate apatite substitutes in vitro.

The present study investigated the osteoclast differentiation potential and paracrine effects of osteoclasts on osteoblast differentiation when the cells were cultured directly on two bone substitutes (BSs): deproteinized bovine bone mineral (DBBM) and carbonate apatite (CO3 Ap). Human primary osteoclasts cultured on the BSs were assessed by tartrate-resistant acid phosphatase (TRAP) and actin ring staining. Thereafter, the mRNA levels of osteoclastic differentiation markers were quantified by real-time PCR. Osteoblast behaviors in response to conditioned media collected from osteoclast cultures were investigated. Interestingly, mature osteoclasts were occasionally observed on the surface of the CO3 Ap granules, whereas very few and small osteoclasts were observed on DBBM. Similarly, real-time PCR analysis showed higher mRNA levels of osteoclast markers, including cathepsin K and TRAP, in the cells cultured on CO3 Ap than in those cultured on DBBM. Furthermore, compared to DBBM, CO3 Ap promoted osteoblast differentiation in human primary osteoblasts, whereas few paracrine effects of osteoclasts cultured with either BS were observed on the osteoblast differentiation potential. These limited results showed that CO3 Ap provided a favorable surface for osteoclast differentiation, as well as osteoblasts, compared to DBBM in vitro.

Preclinical study for the treatment of diabetes mellitus using ß-like cells derived from human dental pulp stem cells.

Aim: The current study assessed whether insulin-producing cells obtained from dental pulp stem cells (DPSCs) can be a new therapeutic approach in a rat model of diabetes mellitus (DM). Materials & methods: Stem cells were differentiated into pancreatic ß cells under hydrogen sulfide exposure via 2D and 3D methods. Each ß-like cell was immunostained and transplanted into DM rats, after which the in vivo therapeutic effect was determined. Results: Immunostaining revealed the expression of various ß-cell markers in each ß-like cell differentiated using the 3D method. DPSC-derived ß-like cell differentiated via the 3D method promoted a sufficient therapeutic effect. Conclusion: The 3D method promoted islet differentiation, indicating that DPSC-derived ß-like cell transplantation could be a new approach for DM treatment.

Radiation-induced malignant fibrous histiocytoma of the maxilla.

Malignant fibrous histiocytoma (MFH) originates from primitive mesenchymal cells and has the capacity for dual histiocytic and fibroblastic differentiation. We report on an MFH of the left maxilla that developed in a 79-year old woman 20 years after surgery and radiation for squamous cell carcinoma (SCC). Postoperative radiotherapy with 70 Gy was administered for a primary neoplasm of SCC of the left maxilla to a localized field through two lateral ports. This secondary neoplasm arose at the site of tumor resection (partial maxillectomy) within the irradiated field, and was resected. The development of sarcomas is a recognized complication of radiation therapy. The final diagnosis after the operation was MFH. The patient died of tumor recurrence at the skull base and within the cranium, 19 months after the operation. Radiation-induced sarcoma is well known, but radiation-induced MFH is relatively rare in the head and neck region. The details of this case are presented with a review of literature.

Bioactivity Evaluation of Biphasic Hydroxyapatite Bone Substitutes Immersed and Grown with Supersaturated Calcium Phosphate Solution.

Recently, the frequency of use of bone substitute materials for the purpose of bone augmentation has increased in implant treatment, but bone formation with bone substitute materials alone is limited. Calcification of bone in the body progresses as Ca2+, H2PO4-, and HPO42- in the body form hydroxyapatite (HA) crystals. In this study, therefore, we prepared a biphasic bone substitute with biological activity to promote bone formation by inducing precipitation and growth of HA crystals on the surface of a bone substitute and evaluated it. Biphasic bone substitute granules were prepared by immersing HA granules in a supersaturated calcium phosphate solution prepared by mixing five medical infusion solutions, the precipitate was analyzed, and the biological activities of biphasic HA granules were evaluated in vitro and in vivo. As a result, the precipitated calcium phosphate crystals were identified as low crystalline HA. On the surface of the HA granules, low-crystalline HA grew markedly as needle-shaped crystals and significantly promoted cell proliferation and bone differentiation. In animal experiments, biphasic HA granules had a significantly higher bone mineral density, new bone volume ratio, and new bone area ratio. Therefore, it suggests that biphasic hydroxyapatite is a useful bone substitute for bone augmentation in dental implant treatment.