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

The present study was deigned to elucidate the effects of the Co-60 gamma irradiation and/or calcium-deficient diet on the periodental tissue formation in rat pups. The pregnant three-week old Sprague-Dawley rats were used for the study. The experimental groups was divided into two groups, irradiation/normal diet group(Group 2) and irradiation/calcium-dificient diet group(Group 1). The abdoment of the rats at the 19th day of pregnancy were irradiated with single absorbed dose of 350 cGy. The rats pups were sacrificed on the 14th day after delivery, and the maxillae including molar tooth sections for light and trasmission electron microscopy. Some of tissue sections for light microscopy were stained immunohistochemically with anti-fibronectin antibodies. The results were as follows ; 1. In the periodontal ligament forming area, the fibroblasts of Group 2 showed irregular arrangement and low activity. The immunoreactivity between the fibroblasts and collagen fibers was decreased, compared with Group 1. The fibroblasts of Group 3 showed atrophic change and clumped nucleus. The collagen fibers showed cystic change and low immunoreactivity to the fibronetin. 2. In the cementum forming area, the cementoblasts of Group 2 showed decrease of number and atrophic change. The cementoblasts of Group 3 showed edematous change, atrophy of cytoplasm, and clumping of nucleus. 3. In the alveolar bone forming area, the bone of Group 2 was thin and various degree of immunoreactivity to the osteonectin, Group 3 showed edematous osteoblasts, fibrous degeneration of bone marrow, and weak immunoreactivity tothe osteonectin.
Animals ; Antibodies ; Atrophy ; Bone Marrow ; Collagen ; Cytoplasm ; Dental Cementum ; Diet* ; Fibroblasts ; Maxilla ; Microscopy ; Microscopy, Electron ; Molar ; Osteoblasts ; Osteonectin ; Periodontal Ligament ; Pregnancy ; Rats* ; Rats, Sprague-Dawley ; Tooth

The purpose of this study was to prove the relationship between arthrographic and clinical features in temporomadibular joint disorders. In order to carry out this study, ninety-eight arthrographic examinations of temporomandibular joints were performed in eighty-two patients who had the temporomandibular joint disorders. As the arthrographic examination, the cases were classfied in three groups, disk displacement with reduction, disk displacement without reduction, within normal limit. After this, the cases were clinically exanmined, and the results were compared and analyzed in each other group. The obtained results were as follows ; 1. As the classification by arthrographic examination, three groups (disc displacement with reduction, disc displacement without reduction, within normal limit) were 41%, 54%, 5% of total cases in this study, respectively. 2. The third decade(65%) was most frequent in this study. The average age of each group (disc displacement with reduction, disc displacement without reduction, within normal limit) was 24, 28, 21, and disc displacement without reduction group was higher than any other group. 3. In the chief complaint, pain was the most frequent in all three groups. Joint sound was also frequent in disc displacement with reduction group, but in disc displacement without reduction group, limitation of mouth openimg was more frequent. 4. Of the various pain, the movement pain was most frequent(61%) in this study. In joint sound, click(63%) was the most frequent in disc displacement with reduction group, but sound history(42%) and no sound(31%) were more frequent in disc displacement without reduction group. 5. The average maximum opening of each group (disc displacement with reduction, disc displacement without reduction, within normal limit) was 44mm, 32.9mm, 44mm, and disc displacement without reduction group was less than any other group. 6. The masticatory disturbance of each group (disc displacement with reduction, disc displacement without reduction, within normal limit) was 53%, 79%, 40%, and the trauma history of each group was 50%, 40%, 60%.
Arthrography* ; Classification ; Humans ; Joints ; Mouth ; Temporomandibular Joint Disorders* ; Temporomandibular Joint*

The purpose of this study was to obtain information on the clinical and radiographic features of the odontomas in the jaws. For this study, the authors examined and analyzed the clinical records and radiographs of 119 patients who had lesion of odontoma diagnosed by clinical and radiographic examinations. The obtained results were as follows ; 1. Odontoma occurred the most frequently in the 2nd decade(45.4%) and occurred more frequently in males(60.5%) than in females(39.5%). 2. The most common clinical symptom was the delayed eruption of the teeth(34.2%). 3. The type of lesions was mainly observed as compound odontoma(80.8%), and internal pattern of the complex odontoma was unevenly radiopaque(73.9%). 4. The compound odontoma frequently occurred in anterior portion of the maxilla(57.7%) and mandible(30.9%), and complex odontoma frequently occurred in anterior portion of maxilla(34.8%) and posterior portion of mandible(30.5%). 5. The effects on adjacent teeth were impaction of teeth(71.7%) and prolonged retention of deciduous teeth(31.7%). 6. The impaction of the teeth occurred in anterior portion of maxilla(44.2%) amd mandible(19.2%), but root resorption of the adjacent teeth were not seen. 7. The boundary to adjacent structure was well-defined, the lesions appear as radiopaque mass with radiolucent rim.
Humans ; Jaw ; Odontoma* ; Root Resorption ; Tooth

The author evaluated the effects of taxol, a microtubular inhibitor, as a possible radiation sensitizer and the production of prostaglandins on three human cancer cell lines(KB, RPMI-2650 and SW-13) and one murine cell line(L929). Each cell line was divided into four groups(control, taxol only, radiation only and combination of taxol and radiation). The treatment consisted of a single irradiation of 10 Gy and graded doses(5, 50, 100, 200, 300, 500 nM) of taxol for a 24-h period. The cytotoxicity of taxol alone was measured at 1 day after(1-day group) and 4 days after(4-day group) the treatment. The survival ratio of cell was analyzed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-dimethyl tetrazolium bromide) test. Prostaglandins(PGE2 and PGI2) were measured in the culture medium by a radioimmunoassay. The results obtained were as follows ; 1. There was a significantly in creased cytotoxicity of KB cells in 4-day group than those in 1-day group. Therr was a high correlation between doses of taxol and cell viability in both groups(1-day group R=0.82741, 4-day group R=0.84655). 2. There was a significantly increased cytotoxicity of RPMI-2650 cells treated with high concentration of taxol in 4-day group than those in 1-day group. Also there was a high correlation between doses of taxol and cell viability in 4-day group(R=0.93917). 3. There was a significantly increased cytotoxicity of SW-13 cell treated with high concentration of taxol in 4-day group than those in 1-day group. However no high correlation was observed between doses of taxol and cell viability in both groups(1-day group R=0.46362, 4-day group R=0.65425). 4. There was a significantly increased cytotoxicity of L929 cells treated with low concentration of taxol in 4-day group than those in 1-day group. At the same time, there was a low correlation between doses of taxol and cell viability in both groups(1-day group R=0.34237, 4-day group R=0.23381). 5. In 1-day group of L929 cells, higher cytotoxicities were observed in the groups treated with 500 nM taxil than given 10 Gy radiation alone showed a radiosensitizing effect by taxol. 6. In addition to L929 cells, all cancer cells treated with a commbinationof taxol and radiation in 4-day group appeared ti have some fragmented nuclei and to float on the medium. In addition, L929 cells appeared to be more confluent. 7. The level of PGE2 production was the highest in the contol KB cells. This appeared to increase in every experimental group of all three cancer except L929 cells. There was a significantly increased production of PGE2 in SW-13 cells treated with a combination taxol and radiation compared to the other experimental groups. 8. The level of PGI2 production in the contol group RPMI-2650 cells was the highest. This appeared to increase in every experimental group of all cells except in SW-13 cells. This also increased signigicantly in RPMI-2650 cells treated with a cimbination of taxol and radiation compared to the other experimental groups.
Cell Line ; Cell Survival ; Dinoprostone ; Epoprostenol ; Humans ; KB Cells ; Paclitaxel* ; Prostaglandins ; Radiation Dosage ; Radiation, Ionizing* ; Radiation-Sensitizing Agents ; Radioimmunoassay

In this study, radiographic evaluation was made using panoramic radiography and cross-sectional tomography of SCANORA in male and female adults in their 20 s on the relationship between the maxillary sinus floor and the apex of the maxillary molar, to test the accuracy and effectiveness of the cross-sectional tomography, and to use this information in the assessment of preop, and postop, root canal treatment, apical surgery, extraction and implantology. Forty-one adults with an average age of 24.4 years were studied panoramic radiography and cross-sectional tomography. In panoramic view and cross-sectional view, the position of the apices of maxillary molars were classified as separated, contacted, or protruded type; the general shape of the maxillary sinus floor was evaluated horizontally and vertically from cross-sectional tomography. The accuracy of each radiography was tested using maxilla from 5 fresh cadavers from the Anatomy Lab at Yonsei University Dental College, and panoramic view and cross-sectional tomography were taken in the same condition as with the patients. The results were as follows ; 1. Panoramic view and cross-sectional view were taken in the maxilla specimen, and the actual distance between the maxillary sinus floor and the tooth apices were measured in the specimen; the median values of the distance from the tooth apices to the maxillary sinus floor in the panoramic view, cross-sectional view and in the acrual maxilla specimen were 2.83mm, 4.51mm, and 4.15mm, respectively. In the cross-sectional view, the measured distance was close to the actual distance but in the panoramic view, the measured distance was far from the actual distance. 2. When the results of the panoramic view and cross-sectional view were compared, 40.5% of the results agreed with each other in the two radiographic methods and buccal roots of the 2nd molar were the closest to the maxillary sinus floor in the cross-sectional tomography. 3. In cross-sectional view, when the vertical relatioship of the maxillary sinus floor and maxillary roots was assessed, in 1st molars, type II (the sinus floor that extends down to the buccolingual furcation area) was predominant, while in 2nd molars, type I (the sinus floor located above the level connecting the buccal and lingual apices) was predominant. In the horizontal relationship, in 1st olars, type II (ths lowest floor of the maxillary sinus located in between the buccal and lingual roots) was predominant; in 2nd molars, type I (the lowest floor of the maxillary sinus located on the buccal side of the buccal roots) and type II appeared in similar frequency. In conclusion, the SCANORA cross-sectional tomography was more effective than the frequently used panoramic view, in that the relationship of the maxillary molars and maxillary sinus floor can be evaluated more accurately and the buccolingual cross-sectional view can also be observed. And maxillary sinus floor that was close to maxillary 2nd molar had tendency to be located on buccal side than that close to 1st molar. Therefore, cross-sectional tomography is an effective and accurate method to evaluate the position of the teeth in relation to the sinus floor preoperative and can be easily used to diagnose localized periapical lesions. Also the image quality obtained was quite satisfactory.
Adult ; Cadaver ; Dental Pulp Cavity ; Female ; Humans ; Male ; Maxilla ; Maxillary Sinus* ; Molar* ; Radiography ; Radiography, Dental, Digital ; Radiography, Panoramic ; Tooth ; Tooth Apex

The present study was designed to elucidate the effects of the Co-60 r irradiation and/or calcium deficient diet on the dentin and cementum formation of rat molar. The pregnant three-week old Sprague-Dawley rat were used for the study. The experimental group was divided into two groups, irradiation/normal diet group and irradiation/calcium-deficient diet group. The control group was non-irradiation/normal diet group. The abdomen of the rats at the 19th day of pregnancy were irradiated with single absorbed dose of 350 cGy. The rat pups were sacrificed on the 14th day after delivery and the maxillae including molar tooth germ were taken. The specimens including the 1st molar tooth germ were prepared to make tissue sections for light and trasmission electron microscopy. Some of tissue sections for light microscopy were stained immunohistochemically with anti-fibronectin antibody. The results were as follows ; 1. The Hertwig s epithelial root sheath cells, which are related to the differentiation of the tooth-forming cells, showed irregular cellular arrangement, decrease of intercellular junctional complex, and decreased immunoreactivity to the fibronectin after irradiation. These were more severe in the irradiation/calcium-deficient diet group. 2. The cementoblasts at the cementum-forming area showed chormatin clupings after irradiation. The immu noreactivity to the fibronectin was weaken after irradiation, especially irradiation/calcium-deficient diet group. 3. The odontoblast at the dentin-forming area showed increase of lysosomes in the cytoplasm and destruction of intercellular junctional complex. The irradiation/calcium-deficient diet group showed decrease of number and density of th electron dense particles and a large number of vacuoles scattered in the dentin matrix. The immunoreactivity was weaken.
Abdomen ; Animals ; Calcium ; Cytoplasm ; Dental Cementum* ; Dentin* ; Diet* ; Fibronectins ; Lysosomes ; Maxilla ; Microscopy ; Microscopy, Electron ; Molar* ; Odontoblasts ; Pregnancy ; Rats* ; Rats, Sprague-Dawley ; Tooth Germ ; Vacuoles

The purpose of this study was to aid in the use of the digital images by edge-detect interpolation for direct digital periapical images using edge-deted interpolation. This study was performed by image processing of 20 digital periapical images; pixel replication, linear non-interpolation, linear interpolation, and edge-sensitive interpolation. The obtained results were as follows ; 1. Pixel replication showed blocking artifact and serious image distortion. 2. Linear interpolation showed smoothing effect on the edge. 3. Edge-sensitive interpolation overcame the smoothing effect on the edge and showed better image.
Artifacts