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Central ossifying fibroma (COF) is the most common benign fibro-osseous lesion of the jaw. This retrospective study evaluated the clinical and histopathologic features of 28 COFs in Taiwanese patients. Methods: Twenty-eight consecutive cases of COF were collected from 1988 to 2006. The clinical data and microscopic features of these cases were reviewed and analyzed. Results: The mean age of patients at the time of diagnosis was 34 years. There were six male and 22 female patients. Twenty-six (93%) cases were found in the mandible and two (7%) in the maxilla. The most common sites for COFs were the molar region (17 cases, 61%), followed by the premolar (8 cases, 28%), and incisor/canine (3 cases, 11%) regions. Bone swelling or expansion (96%, 26/27) was the most frequent clinical presentation. Six (21%) COFs presented as a radiolucent lesion, 17 (61%) as a mixed lesion, and five (18%) as a radio-opaque lesion. No recurrence of the lesion was found after surgical excision in this series. Microscopically, COFs showed trabeculae of woven bone (25 cases) and/or lamellar bone (5 cases) and/or spherules of cementoid (19 cases) in a cellular fibrous connective tissue stroma. The stromal component was highly cellular in 21 cases, moderately cellular in seven cases, prominently vascular in 11, and collagenous in six. Conclusion: COFs occur more frequently in female patients and in those in the second to fourth decades of life. The most commonly affected site is the mandible, especially the molar region. The majority of COF lesions present as a well-defined, mixed lesion radiographically. Most COFs can be treated by conservative surgical excision without subsequent recurrence.

Background. Oral leukoplakia (OL) is a common oral precancerous lesion. Cotton-swab cryotherapy (CSC) is commonly used for treating skin lesions but is rarely used for treating OL lesions. Methods. Sixty OL lesions were treated by CSC once every 2 weeks until complete regression (CR) of the lesion had been achieved. Results. CR was achieved in all 60 OL lesions after an average of 6.3 treatments with cryotherapy. The number of CSC treatments required to achieve CR was significantly fewer for OL lesions on oral mucosal sites other than the tongue, those <2 cm2, those with epithelial dysplasia, and those with a surface keratin thickness of <55 μm. Multivariate analyses showed that only the location and area of the OL lesions were independent factors influencing the number of CSC treatments required to achieve CR. Conclusion. For OL lesions with a mean surface area of ≤1.8 cm2, CR can be achieved with fewer than 7 CSC treatments on average. CSC is a simple, safe, easy, conservative, and acceptable treatment modality for OL lesions. © 2009 Wiley Periodicals, Inc. Head Neck, 2009 [ABSTRACT FROM AUTHOR]

The synthesis of cerium-doped yttrium aluminum garnet (YAG:Ce) phosphor of different sizes with uniform size distribution was carried out using solid-state reaction followed by grinding and sieving method. The effect of particle size distribution of YAG:Ce phosphors on the photoluminescence (PL) properties was investigated. The results demonstrate that the uniform size distribution and particle size affects the packaging performance in white light emitting diode (LED) applications. The YAG:Ce phosphors with different particle sizes were packaged in white LEDs using different amounts of each phosphors in order to get similar efficiency as that of commercially available YAG:Ce phosphors. It was observed that minimum amount of phosphor material is required for smaller particle size for getting the similar efficiency as that exhibited by commercially available YAG:Ce phosphors. The results are particularly interesting in view of reducing the cost of current LEDs by lowering the amount of phosphors without compromising the efficiencies of final LED package. A systematic study of YAG:Ce phosphors on the packing performance in white LEDs is reported. [ABSTRACT FROM AUTHOR]

Overexpression of p34cdc2 has been demonstrated in a variety of human cancers and found to be significantly associated with the tumor size, lymph node metastasis, clinical stage, and prognosis of these cancers. In this study, we examined the expression of p34cdc2 in 81 specimens of oral squamous cell carcinoma (OSCC), 95 specimens of oral epithelial dysplasia (OED; 29 mild, 43 moderate, and 23 severe OED cases), and 14 specimens of normal oral mucosa (NOM) by immunohistochemistry. The cytoplasmic p34cdc2 labeling indices (Us) in OSCC, OED, and NOM samples were calculated and compared among the groups. Correlations of the cytoplasmic p34cdc2 LIs in OSCCs with clinicopathological parameters and survival of OSCC patients were analyzed statistically. We found that the mean cytoplasmic p34cdc2 LIs significantly increased from NOM (6% ± 7%) through mild (18% ± 10%), moderate (23% ± 11%), and severe OED (40% ± 22%) to OSCC samples (73% ± 20%, p=0.000). A significant correlation was found between the higher mean cytoplasmic p34cdc2 Us and positive regional lymph node metastases (p=0.013), more-advanced clinical stages (p=0.022), and higher differentiation of cancer cells (p=0.027). Our results suggest that the p34cdc2 expression is an early event in oral carcinogenesis and may play an important role in oral carcinogenesis. Cytoplasmic p34cdc2 LIs can be used as a biomarker to predict the progression of OSCCs in Taiwan. [ABSTRACT FROM AUTHOR]

Overexpression of cellular inhibitor of apoptosis protein 1 (cIAP-1) has been demonstrated in a variety of human cancers and found to be associated with lymph node metastasis, clinical stage, recurrence, and prognosis of these cancers. In this study, we examined the expression of cIAP-1 protein in 73 specimens of oral squamous cell carcinoma (OSCC), 76 specimens of oral epithelial dysplasia (OED), and 31 specimens of normal oral mucosa (NOM) by immunohistochemistry (IHC). The cytoplasmic cIAP-1 labeling indices (LIs) in OSCC, OED, and NOM samples were calculated and compared among the groups. Correlations between the cytoplasmic cIAP-1 LIs in OSCCs and clinicopathological parameters and survival of OSCC patients were analyzed statistically. We found that the mean cytoplasmic cIAP-1 LIs significantly increased from NOM (23% ± 22%) through OED (50% ± 25%) to OSCC samples (73% ± 17%) (p = 0.000). A significant correlation was found between the higher mean cytoplasmic cIAP-1 Us and OSCCs with positive lymph node metastasis (p=.000) and more-advanced clinical stages (p = 0.045). However, the expression of cIAP-1 protein was not associated with OSCC patient survival. Our results suggest that the increased expression of cIAP-1 is an early event in oral carcinogenesis, and cIAP-1 may be a biomarker for OSCCs. Measuring the amount of cytoplasmic cIAP-1 expression in OSCC samples may predict the oral cancer progression in Taiwanese patients. [ABSTRACT FROM AUTHOR]

Peripheral ossifying fibromas (POFs) present as tumor-like growths on the gingiva or alveolar mucosa. They are often misdiagnosed as a fibrous epulis, a pyogenic granuloma, or a peripheral giant cell granuloma. Data on 27 patients each with a POF diagnosed and treated in our institute during the period from 1988 to 2006 were analyzed in this study. There were 16 female and 11 male patients. The mean age of the 27 patients at the time of diagnosis was 38 years. The sizes of the 27 POFs ranged from 5 to 30 mm in greatest dimension with an average size of 15 mm. Clinically, they usually presented as reddish, firm, pedunculated, or sessile masses on the gingiva or alveolar mucosa. The overlying mucosa was either completely intact (13 cases) or focally ulcerated (14 cases). The more-common sites for POF lesions were the premolar and molar regions of the maxilla (52%). All patients ultimately received total surgical excision of the lesion. Of the 27 POFs, 4 (15%) experienced a single recurrence. Histologically, the POFs showed trabeculae or islands of mineralized products in a cellular fibrous connective tissue stroma. The mineralized products were defined as woven bone (22 cases), lamellar bone (6 cases), cementoid (12 cases), or amorphous material of dystrophic calcification (4 cases). We concluded that POFs occur more commonly in female patients aged < 50 years. The more-common sites for POFs were the premolar and molar regions of the maxilla in this series. The recurrence rate for our POF lesions was 15%. [ABSTRACT FROM AUTHOR]