The purpose of this study was to aid in the prediction of tumor cell tolerance to radiotherapy and/or chemotherapy. For this study, cell surviving curves were obtained for human epidermoid carcinoma A-253 cell line using semiautomated MTT assay. 2, 4, 6, 8, 10 Gy were irradiated at a dose rate of 210 cGy/min using 60Co Irradiator ALDORADO 8. After irradiation, A-253 cell lines(2x10(4) cells/ml) were exposed to bleomycin or cisplatin for 1 hour. The viable cells were determined for each radiation dose with/without 2 ug/ml of drug at the 3rd day. And they were compared to control values. The results were obtained as follows: 1. The surviving curve with gentle slope was obtained after irradiation of 2, 4, 6, 8, 10 Gy on A-253 cell line. 2. The cytotoxicity of bleomycin or cisplatin at the concentration of 2 ug/ml was great on A-253 cell line. But, there was no significant difference between the cytotoxicity of bleomycin and that of cisplatin. 3. There were significant differences of surviving fractions after irradiation with 2 ug/ml of bleomycin compared with irradiation only on A-253 cell line. 4. There were significant differences of surviving fractions after irradiation with 2 ug/ml of cisplatin compared with irradiation only on A-253 cell line. 5. There were no significant differences of surviving fractions between the groups of irradiation with bleomycin and the groups of irradiation with cisplatin on A-253 cell line.
Bleomycin ; Carcinoma, Squamous Cell ; Cell Line* ; Cisplatin ; Drug Therapy ; Humans ; Radiation Tolerance* ; Radiotherapy

This study was performed to demonstrate the effect of linear or nonlinear contrast enhancement on subtraction images. Three different textures were radiograped on dental film. The first radiograph was taken without the presence of an object. the second, which showed trabucular bone, was taken of the molar area of a human. the third radiograph was taken of the coronal part of molars. Each film was digitized into a 1312 X 1024 pixel X 8 bit depth matrix by means of a Nikon 35 mm film scanner(LS-3510AF, Japan) with fixed gain and internal dark current correction to maintain constant illumination. The scanner was interfaced to a Macintosh LC III computer(Apple Computer, Charlotte, N.C.). This resulted in three pairs of images, including different textures-plain, bone and enamel. Digital regular, linearly and nonlinearly enhanced subtraction was performed. Computer software was used to simulate lesions in the shape of a 2D-Gaussian curve on each of a pair of images. The each subtraction images were presented in a random sequence to two groups of 10 observers(students and dentists). ROC analysis was used to compare observer performance. The following results were obtained; 1. All of LCE subtraction, equalized subtraction and regular subtraction images of plain texture were diagnosed the best by far. 2. The data revealed a siginificant LCE effect in both the student group and the expert group. 3. Clinical expertise was a helphul factor for the observers in this study.
Dental Enamel ; Humans ; Lighting ; Molar ; ROC Curve

This study was performed in order to identify changes of the plasma membrane proteins in rat submandibular gland tumors induced by 7,12-dimethylbenz[a]anthracene [DMBA] and X-irradiation. Two kinds of tumor associated membrane proteins (protein A and B) were isolated with 3 M KCl extraction from rat submandibular gland tumors induced by DMBA and X-irradiation. To identify their antigenicities, immunoelectrophoresis and double immunodiffusion was carried out with various proteins extracted from liver, heart, skin and pancreas of adult rats and from embryonic liver, heart and skin. The rabbit antisera against the protein A did not cross-react with any of the proteins extracted from the above mentioned tissues, suggesting that protein A might be tumor specific antigen. However, the rabbit antisera against protein B was precipitated with proteins extracted from the liver of adult and embryonic rats. Polyacrylamide gel electrophoresis of these two proteins (A and B) showed that protein A was a dimer with molecular weights of 69,000 and 35,000 dalton, whereas protein B was a monomer with molecular weight of 50,000 dalton.
9,10-Dimethyl-1,2-benzanthracene* ; Adult ; Animals ; Cell Membrane ; Electrophoresis, Polyacrylamide Gel ; Heart ; Humans ; Immune Sera ; Immunodiffusion ; Immunoelectrophoresis ; Liver ; Membrane Proteins ; Molecular Weight ; Pancreas ; Rats* ; Skin ; Staphylococcal Protein A ; Submandibular Gland*

The purpose of this study was to compare E-speed film, CDR, and modified CDR images by means of observing some artificial defects of alveolar bone wall in the sound human dried mandibles. High diagnostic accuracy was shown in 1 wall and 4 wall defects by all 5 observers (2 Radiologists, 2 Periodontists, 1 General practitioner), but the diagnosis in 2 wall and 3 wall defects was inaccurate. Modified CDR images had the more diagnostic accuracy than E-speed film and CDR images, but there was no statistical difference among them. Finally, radiologist used modified CDR images more than others and used equalization effect more than the change in contrast and/or brightness.
Diagnosis ; Humans ; Mandible ; Radiographic Image Enhancement*

The purpose of this study was to evaluate the accuracy and usefulness of spiral tomography through the comparison and analysis of SCANORA cross-sectional tomographs and DentaScan computed tomographic images of dry mandibles taken by a SCANORA spiral tomographic machine and a computed tomographic machine. Thirty-one dry mandibles with full or partial edentulous areas were used. To evaluate the possible effect of location in the edentulous area, it was divided into 4 regions of Me (region of mental foramen), M1 (the midportion between Me and M2), M2 (the midportion between mental foramen and mandibular foramen) and S (the midportion of the mandibular symphysis). A ZPC column (sized 4 mm X 5 mm) was seated on the edentulous regions of Me, M1, M2 and S using the acrylic stent. Then SCANORA spiral tomography and computed tomography were taken on the edentulous regions which contained the ZPC column. The ZPC columns and cross-sectional images of the mandible were measured in the radiographs by three observers and the differences between the two imaging modalities were analysed. The results were as follows: 1. In comparing the actual measurements of the ZPC column and measurements in the radiographs, the mean error of the DentaScan computed tomography was 0.07 mm in vertical direction and -0.06 mm in horizontal direction, while the mean error of the SCANORA spiral tomography was 0.06 mm in vertical direction and -0.12 mm in horizontal direction. There was a significant difference between the two radiographic techniques in the horizontal measurement of the ZPC column of the symphysis region (p<0.05). but there was no significant difference in the measurements of other regions>0.05). 2. In measurements of the distance from the alveolar crest to the inferior border of the mandible (H), and of the distance from the alveolar crest to the superior border of the mandibular canal (Y), there was no significant difference between the two radiographic techniques (p>0.05). 3. In measurements of the distance from the lingual border of the mandible to the buccal border of the mandible (W), and of the distance from the lingual border of the mandible to the lingual border of the mandibular canal (X), there was a significant difference between the two radiographic techniques in measurements of the midportion between the mental foramen and the mandibular foramen (M2) (p<0.05). but there were no significant differences in measurements of the other regions of symphysis>0.05). 4. Considering the mean range of measurements between observers, the measurements of SCANORA spiral tomography showed higher value than those of DentaScan computed tomography, except in measurements of symphysis (S). 5. On the detectability of the mandibular canal, there was no significant difference between the two radiographic techniques (p>0.05). In conclusion, SCANORA spiral tomography demonstrated a higher interobserver variance than that of DentaScan computed tomography for implant site measurements in the posterior edentulous area of the mandible. These differences were mainly the result of difficulty in the detection of the border of the mandible in SCANORA spiral tomography. But considering the cost and the radiation exposure, SCANORA spiral tomography can be said to be relatively good radiographic technique for implant site measurement.
Mandible* ; Radiography, Dental, Digital ; Stents

This study was performed to prepare the quantitative method of judging the sensitive prognosis of chronic apical periodontitis as early as possible. The subjects were 25 cases with periapical radiolucencies of which were treated with endodontic treatment. Serial radiographs were taken by standardized method longitudinally. The density slice function of digital radiographic system were employed for quantitative and longitudinal assessment of the radiolucent area and the condensing osteitis simultaneously. Obtained results were as follows: 1. The amount of bone repair after endodontic treatment could be detected quantitatively by the density slice function of digital radiographic system. 2. Within the 6-week period after root canal filling, the prognosis could be evaluated by assessment both radiolucent area and condensing osteitis on digital radiographic system. 3. The pattern of bone repair showed peripheral type in most cases from the 6th week after root canal filling. 4. In longitudinal change, bone repair showed two patterns; the succeeding reduction of radiolucent area showing the increase of condensing osteitis in size till 6th week and following by static state or reduction tendency and the reduction following the initial increase of both areas. 5. Cases with pulpitis by trauma showed initial increase of condensing osteitis at 2nd week, marked reduction of radiolucent area and condensing osteitis at 6th week, and approximately normal bone state at 8th week after root canal filling.
Dental Pulp Cavity ; Osteitis ; Periapical Periodontitis ; Prognosis ; Pulpitis ; Radiography*

This study is designed to determine the artificial incipient proximal caries lesion detectability by dentists on Ektaspeed Plus film using ROC analysis. Sixteen premolars and 30 molars, which have 52 proximal caries-like demineralized lesions using acid-gel technique were added to 20 sound premolars and 30 sound molars to make 24 plaster bolcks. Each block with 4 teeth and 6 contacting proximal surfaces was placed in an optical bench to take 12 bitewing radiographs with Ektaspeed Plus film. Thirty-six dentists acted as observers to evaluated the proximal lesions using five rating scales for ROC analysis. They were also asked to determine the presence or absence of the proximal caries. The true status of the proximal caries was established by the consensus of three oral and maxillofacila radiologists. For evaluation of intra-observer agreement, 9 dentist reread the radiographs at an interval of 1 month. The Pearson correlation coefficient for the intra-observer agreement was 0.746(good agreement). Ten observer's data set were degenerated. The mean area under ROC curve from 26 obsevers was 0.806 and standard deviation was 0.061. The sensitivity and the specificity of the binary response were 0.17(SD=0.11) and 0.78(SD=0.17) respectively. The binary response only reveal a single values of sensitivity and the specificity. The ROC analysis to assess the diagnostic accuracy in caries detection, which producing estimates of sensitivities for all specifities, yield more comprehensive measures of diagnostic performance than single values for sensitivity and specificity.
Bicuspid ; Consensus ; Dataset ; Dentists ; Humans ; Molar ; ROC Curve* ; Sensitivity and Specificity ; Tooth ; Weights and Measures

The following conclusions were obtained from the non-reconstructed and reconstructed subtraction images of the standard intraoral radiographs which were taken with paralleing technique with Rinn XCP only and with occlusal bite registration for geometric standardization using bilateral mandibular premolar and molar regions of two dry humad skulls. 1. The SD of the overall subtraction images of the premolars and molars of the non-reconstructed, tnat is, the manual superimposition showed statistically significant difference between the non-registered and registered groups. 2. In non-reconstructed and non-registered cases, the quality of the subtraction images were improved when superimposition was focally done and this was more evident in areas where the radiographic imaged tend to be distorted due to anatomic readons. 3. In non-restructed and registered cases, the subtraction images were consistent regardless of the anatomic site or the focus superimposition. This means that the geometric standardization with only occlusal bite registration could produce serial radiographs which is suitable for subtraction. 4. The SD of the overall subtraction images of the premolars and molars of the reconstructed, that is, the automatic superimposition showed statistically insignificant difference between the non-registered and registered groups. This means that using reconstruction, subtraction radiography is possible without occlusal bite registration. 5. In reconstructed and non-registered cases, compatible quality of the subtraction images were obtained regardless of the anatomic site or area of the corresponding points. 6. In reconstructed and registered cases, best subtraction images whose quality showed sensitivity to the areas of corresponding points were obtained.
Bicuspid ; Jaw Relation Record ; Molar ; Radiography* ; Skull

This study was designed to reveal the correlationship between the internal derangement state of TMJ and clinical characteristics including pain and mandibular dusfuntion. One hundred and twenty five subjects with TMJ signs and symptoms were chosen for two years. The level of pain and mandibular dysfuntion were evaluated by Visual Analog Scale(VAS) and Craniomandibular Index(CMI). The diagnostic categories of TMJ internal derangement were determined by arthrography and they included normal disc position, anterior disc displacement with reduction(ADDR), rotational disc displacement with reduction(RDDR), andterior disc displacement without reduction(ADDNR), and rotational disc displacement without reduction(RDDNR). Also disc perforation was used as a criteria to divide the diagnostic subgroups. The obtained results were as follows ; 1. The patient distribution of each group was 5 in normal disc position(4%), 40 in ADDR(32%), 30 in RDDR(24%), 34 in ADDNR(27%), and 16 in RDDNR(13%). 2. Perforation was observed in 8% of ADDR, 10% of RDDR, 32% of ADDNR, and 19% of RDDNR. 3. CMI of perforation group was higher than that of reduction or normal group(P<0.005), but vas showed no significant difference. 4. CMI of non-reduction group was higher than that of non-perforation group in reduction group(P<0.05). 5. There were no significant differences of CMI and VAS between anterior disc displacement group and rotational disc displacement group in both reduction and non-reduction group. 6. CMI of RDDNR group was higher than that of RDDR group(P<0.05). 7. There were no significant difference of CMI and VAS between bilateral involvement group and unilateral involvement group(p>0.05).
Arthrography ; Humans ; Temporomandibular Joint*

The purpose of this study was to perform the radiographic measurements and temporomandibular joint evaluation in mandibular asymmetry. For this study, thirty-two patients who have mandibular asymmetry were selected and submentovertex, panoramic and lateral corrected tomographic radiagraphs were taken. Horizontal and vertical analysis using various landmarks on these radiographs were performed. Also radiographic and clinical evaluation of temporomandibular joint were obtained. Ther results were as follows ; 1. On the submentovertex radiograph, the mean distance of Pogonion to midline was 5.0(+/-)3.8mm. 2. The mean distance of Pogonion to Gonion between the deviated and the contra-lateral side(P<0.001). 3. The distance difference of Pogonion to Gonion between the deviated and the contra-lateral side was significantly realated to the degree of asymmetry(P<0.001). 4. On panoramic radiagraph,the condylar height of the contral-lateral side was significantly longer than the one of the deviated side(P<0.001). 5. On lateral corrected tomogram, bony of temporomandibular joint was observed in 11 condyles of the deviated side and 9 condyles of the contra-lateral side. Erosion and ostephyte were the most common changes in both the deviated and the contra-lateral sides.
Humans ; Temporomandibular Joint