Effects of irradiation on TGF-beta1 mRNA expression and calcific nodule formation in MC3T3-E1 osteoblastic cell line / 대한구강악안면방사선학회지

PURPOSE: To investigate the effects of irradiation on transforming growth factor beta1 (TGF-beta1) mRNA expression and calcific nodule formation in MC3T3-E1 osteoblastic cell line. MATERIALS AND METHODS: Cells were cultured in alpha-minimum essential medium (alpha-MEM) supplemented with 10% fetal bovine serum and antibiotics. When the cells reached the level of 70-80% confluence, culture media were changed with alpha-MEM supplemented with 10% FBS, 5 mM beta-glycerol phosphate, and 50 microgram/mL ascorbic acid. Thereafter the cells were irradiated with a single dose of 2, 4, 6, 8 Gy at a dose rate of 1.5 Gy/min. The expression pattern of TGF-beta1 mRNA, calcium content and calcific nodule formation were examined on day 3, 7, 14, 21, 28, respectively, after the irradiation. RESULTS: The amount of TGF-beta1 mRNA expression decreased significantly on day 7 after irradiation of 4, 6, 8 Gy. It also decreased on day 14 after irradiation of 6, 8 Gy, and decreased on day 21 after irradiation of 8 Gy. The amount of calcium deposition decreased significantly on day 7 after irradiation of 4, 8 Gy (P.0.01) and showed a decreased tendency on day 14, 21 after irradiation of 4, 6, 8 Gy. The number of calcific nodules was decreased on day 7 after irradiation of 4, 8 Gy. CONCLUSION: Irradiation with a single dose of 4, 6, 8 Gy influences negatively the bone formation at the molecular level by affecting the TGF-beta1 mRNA expression that was associated with proliferation and the production of extracellular matrix in MC3T3-E1 osteoblastic cell line.

Bone change of mandibular condyle using cone beam computed tomography / 대한구강악안면방사선학회지

PURPOSE: To assess bone changes of mandibular condyle using cone beam computed tomography (CBCT) in temporomandibular disorder (TMD) patients. MATERIALS AND METHODS: 314 temporomandibular joints (TMJs) images of 163 TMD patients were examined at the Department of Oral and Maxillofacial Radiology, Chonbuk National University. The images were obtained by PSR9000N (Asahi Roentgen Co., Japan) and reconstructed by using Asahivision software (Asahi Roentgen Co., Japan). The CBCT images were examined three times with four weeks interval by three radiologists. Bone changes of mandibular condyle such as flattening, sclerosis, erosion and osteophyte formation were observed in sagittal, axial, coronal and 3 dimensional images of the mandibular condyle. The statistical analysis was performed using SPSS 12.0. Intra- and interobserver agreement were performed by 3 radiologists without the knowledge of clinical information. RESULTS: Osteophyte (2.9%) was found more frequently on anterior surface of the mandibular condyle. Erosion (31.8%) was found more frequently on anterior and medial surfaces of the mandibular condyle. The intraobserver agreement was good to excellent (k=0.78-0.84), but interobserver agreement was fair (k=0.45). CONCLUSION: CBCT can provide high qualified images of bone changes of the TMJ with axial, coronal and 3 dimensional images.

Peripheral ameloblastoma: A case report / 대한구강악안면방사선학회지

Peripheral ameloblastoma is an extremely rare odontogenic soft tissue tumor with histologic characteristics similar to those of the intraosseous ameloblastoma. It appears in the gingiva and oral mucosa. And it usually does not show any bone involvement on radiographs, except for saucer shaped erosion of underlying alveolar bone. Recurrence is considered uncommon. We report a case of peripheral ameloblastoma with bone involvement. Histologically it presented with follicles and nest of tumor cells with palisading pattern. And radiographs showed the typical saucer shaped alveolar bone erosion at the distal area of right mandibular third molar. At 6-month follow-up after operation, no local recurrence was noted.

Ankylosing Spondylitis Associated With Bilateral TMJ Ankylosis / 대한구강악안면방사선학회지

A 31-year-old male with severe limitation of mouth opening was referred to our department of Chonbuk National University Hospital. The physical status of the patient was hyposthenic. Extraoral examination showed no condylar movement of the both temporomandibular joints, no pain, no faical swelling or paresthesia. Intraoral examination showed several cervical caries on the upper anterior teeth, and gingival swelling on the whole dentition. Transcranial view showed no condylar movement, and narrowing of joint spaces. Chest P-A view showed straightening of thoracic, lumbar spine, and squaring of vertebrae of the same spines. Conventional lateral radiograph of cervical spine showed calcification of the intervertebral ligament. Computed tomograph showed extensive bone formation between temporal bone and the both condylar heads. Labortory findings showed positive reaction on HLA-B27 histocompatibility antigen and increased level of IgA, IgG, ESR. Based on the clinical, radiographic, and the labortary findings, final diagnosis was made as bony ankylosis of the both temporomandibular joints secondary to ankylosing spondylitis.

Optimum image compression rate maintaining diagnostic image quality of digital intraoral radiographs / 대한구강악안면방사선학회지

PURPOSE: The aims of the present study are to determine the optimum compression rate in terms of file size reduction and diagnostic quality of the images after compression and evaluate the transmission speed of original or each compressed images. MATERIALS AND METHODS: The material consisted of 24 extracted human premolars and molars. The occlusal surfaces and proximal surfaces of the teeth had a clinical disease spectrum that ranged from sound to varying degrees of fissure discoloration and cavitation. The images from Digora system were exported in TIFF and the images from conventional intraoral film were scanned and digitalized in TIFF by Nikon SF-200 scanner(Nikon, Japan). And six compression factors were chosen and applied on the basis of the results from a pilot study. The total number of images to be assessed were 336. Three radiologists assessed the occlusal and proximal surfaces of the teeth with 5-rank scale. Finally diagnosed as either sound or carious lesion by one expert oral pathologist. And sensitivity and specificity and kappa value for diagnostic agreement was calculated. Also the area(Az) values under the ROC curve were calculated and paired t-test and oneway ANOVA test was performed. Thereafter, transmission time of the image files of the each compression level were compared with that of the original image files. RESULTS: No significant difference was found between original and the corresponding images up to 7%(1:14) compression ratio for both the occlusal and proximal caries(p<0.05). JPEG3(1:14) image files are transmitted fast more than 10 times, maintained diagnostic information in image, compared with original image files. CONCLUSON: 1:14 compressed image file may be used instead of the original image and reduce storage needs and transmission time.