39-year-old female had been treated for the exophytic mass on buccal aspect of the left maxillary posterior area 2 years and 8 months ago. Tentative diagnosis was obtained as fibrous dysplasia on clinical and radiographic examinations and histopathologic findings revealed as osteochondroma after bone trimming at that time. She revisited for the treatment of recurred lesions. We reviewed this case with clinical, radiologic and histopathologic standpoints retrospectively, and came to a conclusion that the tumor primarily occurred was juxtacortical osteogenic sarcoma and recurred due to inadequate treatment and then expanded over intramedullary. This case shows that the diagnosis of osteosarcoma should take account of the patient history, clinical, radiographic and histopathologic findings and it requires attentive follow up check. Retrospectively reviewed results were as follows ; At first visit, oral examination revealed a bony hard swelling on the buccal aspect of the left maxillary posterior area. Radiographically, a dense radiopaque mass was noted on the site. The lesion showed hot uptake of 99mTc-MDP. Histopathologic diagnosis was done as osteochondroma, but it was considered as osteogenic sarcoma when compared with the recurrent lesion. When she revisited for the treatment of multiple bony swelling on the left maxilla, radiograms showed typical features of malignancy such as widening of periodontal ligament space and sun-ray appearace, and coincided with benign characters as follows ; relatively well circumscribed lesion and expansion and displacement of the adjacent structures. Finally, histopathologic findings of the lesion was well differentiated chondroblastic osteogenic sarcoma.
Adult ; Chondrocytes* ; Diagnosis ; Diagnosis, Oral ; Female ; Follow-Up Studies ; Humans ; Maxilla* ; Osteochondroma ; Osteosarcoma* ; Osteosarcoma, Juxtacortical ; Periodontal Ligament ; Retrospective Studies ; Technetium Tc 99m Medronate

The calcifying epithelial odontogenic tumor is a rare benign odontogenic neoplasm which was first described by Pindborg in 1955 and accounts for less than 1% of all odontogenic tumors. The tumor occurs primarily in the molar-premolar region of the mandible, and 52% of cases are associated with an unerupted tooth. The clinical feature is most commonly a slow-growing painless swelling. The tumor may show considerable radiographic variation and usually characteristic histopathologic features. In this study, we report a case of the calcifying epithelial odontogenic tumor on the left mandibular body and ramus area in a 28-year-old male with a brief review of the concerned literatures.
Adult ; Humans ; Male ; Mandible ; Odontogenic Tumors ; Tooth, Unerupted

The occurrence of PVNS in the TMJ is very rare. We report a case of PVNS which was misdiagnosed as a parotid tumor at first. CT and conventional radiograph revealed a well difined mass demonstrating higher attenuation than adjacent soft tissue. Erosion, expansion of the cortical plate of the mandibular condyle and sclerotic change beneath the margin of the lesion were also shown. MRI demonstrated well defined mass of very low signal intensity on both T1 and T2 image due to ferromagnetic effect and more clearly delineated the extent of the lesion. Ultrasonogram showed homogenous hypoechoic lesion growing toward both condyle and adjacent soft tissue. Histopathologic findings and characteristic appearance of the various imaging method were discribed and the usefulness of these image for diagnosis and pretreatment evaluation of the PVNS were also discussed on this paper.
Diagnosis ; Diagnostic Imaging* ; Magnetic Resonance Imaging ; Magnets ; Mandibular Condyle ; Synovitis, Pigmented Villonodular* ; Temporomandibular Joint* ; Ultrasonography

A cystic compound odontoma in the maxillary sinus occured in a 13-years-old boy, who had missing right upper third molar without having the hostory of extraction of the wisdom tooth. He complained nasal stuffimess, headache, and pain on the affected face, resembling any sign and symptoms of the maxillary sinus problems. The cysitc compound, sized 2 x 1.5 cm in diameter was pedunculated and attached on the posterior wall of the right maxillary sinus and above the antral floor. The location of the compound odontoma in the maxillary sinus was confirmed after panoramic, waters, spiral tomographic, CT examinations and surgical exploration. Irs location was on the medical, posterior, superior to the normal position of the maxillary third molar or the maxiilary dental arch. The cystic odontoma in the maxillary sinus made the patient have the sings and symptoms of mazillary sinustis. The cystic compound dodntoma might be originated from the dental lamina of the missing upper right thred molar. The "V principle" of the upper jaw growth and the pneumatization process fo the maxillary sinus could explain why the compound odontoma had peduncular shape and the location of odontoma was on the demial, superior to the normal position of the maxillary dental arch.
Dental Arch ; Headache ; Humans ; Jaw ; Male ; Maxillary Sinus* ; Maxillary Sinusitis ; Molar ; Molar, Third ; Odontoma* ; Water

For the successful endodontic treatment, root canal should be cleaned thoroughly by accurate mechanical and chemical canal preparation and sealed completely with canal filling material without damaging the periapical tissues. The accuracy of the root canal length measurement is a prerequisite for the success of the endodontic treatment, and the root canal length is often determined by the standard periapical radiographs and digital tactile sense. In this study, the accuracy and the clinical usefulness of Digora(R), an intraoral digital imaging processor and the conventional standard radiographs were compared by measuring the length from the top of the file to the root apex. 30 single rooted premolars were invested in a uniformly sized blocks and No.25 K-file was inserted into and fixed in each canal. Each block was placed in equal distance and position to satisfy the principle of the bisecting angle and paralleling techniques and Digora(R) system's image and standard periapical radiographs were taken. Each radiograph was examined by 3 different observers by measuring the length from top of the file to the root apex and each data was compared and analyzed. The results were as follows; 1. In the bisecting angle technique, the average difference between the Digora(R) system and standard periapical radiograph was 0.002 mmand the standard deviation was 0.341 mmwhich showed no statistically significant difference between the two systems(p>0.05). Also, in the paralleling technique, the average difference between these two system was 0.007 mmand the standard deviation was 0.323 mmwhich showed no statistically significant difference between the two systems(p>0.05). 2. In Digora(R) system, the average difference between the bisecting angle and paralleling technique was -0.336 mmand the standard deviation was 0.472 mmwhich showed a statistically significant difference between the two techniques(p<0.05). also> 3. In Digora(R) system and the standard periapical radiographs, there was a statistically significant difference between the measurement using the bisecting angle technique and the actual length(p<0.05). but there was no statistically significant difference between the measurement using the paralleling technique and the actual length>0.05). In conclusion, the determination of the root canal length by using the Digora(R) system can give us as good an image as the standard periapical radiograph and using the paralleling technique instead of the bisecting angle technique can give a measurement closer to the actual canal length, thereby contributing to a successful result. Also, considering the advantages of the digital imaging processor such as decreasing the amount of exposure to the patient, immediate use of the image, magnification of image size, control of the contrast and brightness and the ability of storing the image can give us good reason to replace the standard periapical radiographs.
Bicuspid ; Dental Pulp Cavity* ; Humans ; Periapical Tissue

The comparative detectability of the artificial periapical defects among Ektaspeed Plus film, digitized and digora images was evaluated. The artificail defects were made in the cancellous bone and cancellous-cortical junction with the size of 1.0x0.8mm2, 1.4x1.1mm2 and 2.8x2.2mm2. The defects in cancellous-cortical junction extended into cortical bone with the depth of 0, 0.5 and 1.0 mm. The results were as follows : 1. In junctional defects Ektaspeed Plus film for 2.8x12.2mm2 defect showed the highest detectability. But siginificant difference were only found between Ektaspeed Plus films and digitized images(p<0.05). 2. Almost all defects within cacellous bone were not detected except a few digitized and Digora images for the size of 2.8x2.2mm2. Digora images for them showed significant differences with Ektaspeed Plus films and digitized images(p<0.05). 3. The sensitinity of all imaging modalities were 0.9 or 1.0 in junctional defects for the size of 1.4x2.2mm2 and 2.8x2.2mm2. For cancellous defects, Digora image showed the highest sensitivity of 0.6 for the size of 2.8x2.2mm2. 4. Siginificant differences for change of exposure time were found in most group of Ektaspeed Plus films and digitized images(p<0.05). But there was no significant differences in Digora images for cacellous defects.
Radiography, Dental, Digital*

In order to achieve a successful endodontic treatment, root canals must be obturated three-dimensionally without causing any damage to apical tissues. Accurate length determination of the root canal is critical in this case. For this reason, I've used the conventional periapical radiography, Digora(R)(digital imaging system) and Root ZX(R) (the frequency dependent type apex locator) to measure the length of the canal and compare it with the true length obtained by cutting the tooth in half and measuring the length between the occlusal surface and the apical foramen. From the information obtained by these measurements, I was able to evaluate the accuracy and clinical usefulness of each systems, whether the thickness of files used in endodontic therapy has any effect on the measuring systems was also evaluated in an effort to simplify the treatment planning phase of endodontic treatment. 29 canals of 29 sound premolars were measured with #15, #20, #25 files by 3 different dentists each using the periapical radiography, Digora(R) and Root ZX. The measurements were then compared with the true length. The results were as follows ; 1. In comparing mean discrepancies between measurements obtained by using periapical radiography(mean error : -0.449+/-0.444 mm), Digora(R)(mean error : -0.417+/-0.415 mm) and Root ZX(R) (mean error : 0.123+/-0.458 mm) with true length, periapical radiography and Digora(R) system had statistically significant differences(p<0.05) in most cases while root zx showed none>0.05). 2. By subtracting values obtained by using periapical radiography, Digora(R) and Root ZX(R) from the true length and making a distribution table of their absolute values, the following analysis was possible. In the case of periapical film, 140 out of 261(53.6%) were clinically acceptable satisfying the margin of error of less than 0.5 mm, 151 out of 261(53,6%) were acceptable in the Digora(R) system while Root ZX(R) had 197 out of 261(75.5%) within the limits of 0.5 mm margin of error. 3. In determining whether the thickness of files has any effect on measuring methods, no statistically significant differences were found(p>0.05). 4. In comparing data obtained from these methods in order to evaluate the difference among measuring methods, there was no statistically significant difference between periapical radiography and Digora(R) system(p>0.05), but there was statistically significant difference between Root ZX(R) and periapical radiography(p<0.05). also, there was statistically significant difference between Root ZX(R) and Digora(R) system(p<0.05). In conclusion, Root ZX(R) was more accurate when compared with the Digora(R) system and periapical radiography and seems to be more effective clinically in determining root canal length. But Root ZX(R) has its limits in determining root morphology and nember of rootd and its accuracy becomes questionable when apical foramen is open due to unknown reasons. Therefore the combined use of Root ZX(R) and the periapical radiography are mandatory. Digora(R) system seems to be more effective when periapical radiographs are needed in a short period of time because of its short processing time and less exposure.
Bicuspid ; Dental Pulp Cavity* ; Dentists ; Humans ; Radiography ; Tooth ; Tooth Apex

Digora system is an intraoral indirect digital radiography system utilizing storage phosphor image plate. It has wide dynamic range which allows it to decrease the patient's exposure time and may increase diagnostic ability through image processing (such as edge enhancement, grey scale conversion, brightness change, and contrast enhancement). And also, it can transmit and storage image information. The purpose of this study was to evaluate the diagnostic ability of artificial proximal caries between Conventional radiograph and Digora images(unenhanced image, brightness & contrast controlled image, and edge enhanced image). ROC(Receiver Operating Characteristic) analysis, paired t-tests, and F-tests were done for the statistical evaluation of detectability. The following results were acquired: 1. In Grade I lesions, the mean ROC areas of Conventional radiograph, Digora unenhanced image, Digora controlled image, and Digora edge enhanced image were 0.953, 0.933, 0.965, 0.978 (p>0.05). 2. In Grade II lesions, the mean ROC areas of Conventional radiograph, Digora unenhanced image, Digora controlled image, and Digora edge enhanced image were 0.969, 0.964, 0.988, 0.994. Among theses areas, there was just statistical significance between Diagnostic abilities of Digora edge enhanced image and Conventional radiograph(p<0.05). 3.In the Interobserver variability, the ROC curve areas of Digora edge enhanced image was lowerest in these areas, regardless of the Carious lesion depths. In conclusion, intraoral indirect digital system, Digora system, has the potential possibility as an alternative of Conventional radiograph in the diagnosis of proximal caries.
Dental Caries ; Diagnosis ; Observer Variation ; Radiographic Image Enhancement ; Radiography ; Radiography, Dental, Digital ; ROC Curve

Image resampling is of particular interest in digital radiology. When resampling an image to a new set of coordinate, there appears blocking artifacts and image changes. To enhance image quality, interpolation algorithms have been used. Resampling is used to increase the number of points in an image to improve its appearance for display. The process of interpolation is fitting a continuous function to the discrete points in the digital image. The purpose of this study was to determine the effects of the seven interpolation functions when image resampling in digital periapical images. The images were obtained by Digora, CDR and scanning of Ektaspeed plus periapical radiograms on the dry skull and human subject. The subjects were exposed to intraoral X-ray machine at 60kVp and 70 kVp with exposure time varying between 0.01 and 0.50 second. To determine which interpolation method would provide the better image, seven functions were compared ; (1) nearest neighbor (2) linear (3) non-linear (4) facet model (5) cubic convolution (6) cubic spline (7) gray segment expansion. And resampled images were compared in terms of SNR(Signal to Noise Ratio) and MTF(Modulation Transfer Function) coefficient value. The obtained results were as follows ; 1. The highest SNR value(75.96dB) was obtained with cubic convolution method and the lowest SNR value(72.44dB) was obtained with facet model method among seven interpolation methods. 2. There were significant differences of SNR values among CDR, Digora and film scan(p<0.05). 3. There were significant differences of SNR values between 60kVp and 70kVp in seven interpolation methods. There were significant differences of SNR values between facet model method and those of the other methods at 60kVp(p<0.05), but there were not significant differences of snr values among seven interpolation methods at>0.05). 4. There were significant differences of MTF coefficient values between linear interpolation method and the other six interpolation methods(p<0.05). 5. The speed of computation time was the fastest with nearest neighbor method and the slowest with non-linear method. 6. The better image was obtained with cubic convolution, cubic spline and gray segment method in ROC analysis. 7. The better sharpness of edge was obtained with gray segment expansion method among seven interpolation methods.
Artifacts ; Humans ; Noise ; Radiography, Dental, Digital ; ROC Curve ; Skull

In orthodontics and orthognathic surgery, cephalogram has been routine practice in diagnosis and treatment evaluation of craniofacial deformity. But its inherent distortion of actual length and angles during projecting three dimensional object to two dimensional plane might cause errors in quantitative analysis of shape and size. Therefore, it is desirable that three dimensional object is diagnosed and evaluated three dimensionally and three dimensional CT image is best for three dimensional analysis. Development of clinic necessitates evaluation of result of treatment and comparison before and after surgery. It is desirable that patient that was diagnosed and planned by three dimensional computed tomography before surgery is evaluated by three dimensional computed tomography after surgery, too. But Because there is no standardized normal values in three dimension now and three dimensional Computed Tomography needs expensive equipments and because of its expenses and amount of exposure to radiation, limitations still remain to be solved in its application to routine practice. If postoperative three dimensional image is constructed by pre and postoperative lateral and postero-anterior cephalograms and preoperative three dimensional computed tomogram, pre and postoperative image will be compared and evaluated three dimensionally without three dimensional computed tomography after surgery and that will contribute to standardize normal values in three dimension. This study introduced new method that computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms, and for validation of new method, in four cases of dry skull that position of mandible was displaced and four patients of orthognathic surgery, computer-simulated three dimensional image and actual postoperative three dimensional image were compared. The results were as follows. 1. In four cases of dry skull that position of mandible was displaced, range of displacement between computer-simulated three dimensional images and actual postoperative three dimensional images in co-ordinates values was from -1.8 mm to 1.8 mm and 94% in displacement of all co-ordinates values was from -1.0 mm to 1.0 mm and no significant difference between computer-simulated three dimensional images and actual postoperative three dimensional images was noticed(p>0.05). 2. In four cases of orthognathic surgery patients, range of displacement between computer-simulated three dimensional images and actual postoperative three dimensional images in co-ordinates values was from -6.7 mm to 7.7 mm and 90% in displacement of all co-ordinates values was from -4.0 to 4.0 mm and no significant difference between computer-simulated three dimensional images and actual postoperative three dimensional images was noticed(p>0.05). Conclusively, computer-simulated three dimensional image was constructed by preoperative three dimensional computed tomogram and pre and postoperative lateral and postero-anterior cephalograms. Therefore, potentiality that can construct postoperative three dimensional image without three dimensional computed tomography after surgery was presented.
Congenital Abnormalities ; Diagnosis ; Humans ; Imaging, Three-Dimensional ; Mandible ; Orthodontics ; Orthognathic Surgery* ; Reference Values ; Skull