Ameloblastic fibro-odontoma is a rare benign mixed odontogenic tumor with histologic characteristics of ameloblastic fibroma and complex odontoma. As with ameloblastic fibroma, it may be asymptomatic or found because of painless swelling and delayed eruption of associated tooth. This report presents a case of ameloblastic fibro-odontoma in the posterior mandible of a 14-year-old girl and analyses its clinical features and radiographic features on plain X-ray film and CT images.
Adolescent ; Ameloblasts* ; Female ; Fibroma ; Humans ; Mandible* ; Odontogenic Tumors ; Odontoma* ; Tooth ; X-Ray Film

PURPOSE: To acquire the useful diagnostic information through the analysis of the clinical and radiological characteristics of mandibular odontogenic keratocyst. MATERIALS AND METHODS: The researchers compared and analysed the clinical and radiological features of 112 cases of mandibular odontogenic keratocyst confirmed by histopathlogic examination. RESULTS: Mandibular odontogenic keratocysts occurred more frequently in males than in females and the incidence is the highest in the 2nd and 3rd decades. These cysts occurred in the mandibular posterior area, angle-ramus area and anterior area 51.8%, 31.2% and 17.0% respectively. These cysts had undulating border (69.6%) rather than smooth border (30.4%). Most of these cysts had well-defined hyperostotic border (94.6%). These cysts caused cortical thinning or expansion (78.6%) rather than no cortical reaction (21.4%). Loss of lamina dura was observed in 72.3%, displacement of tooth appeared in 35.7% and root resorption appeared in 12.5% of cases. In 71% of cases, displacement of mandibular canal was observed. Internal patterns of lesional radiolucency were even (61.6%) or uneven (38.4%). CONCLUSION: These results would be helpful in diagnosing of mandibular odontogenic keratocyst.
Female ; Humans ; Incidence ; Male ; Odontogenic Cysts* ; Radiography ; Root Resorption ; Tooth

PURPOSE: To acquire the useful diagnostic information through the analysis of the clinical and radiological characteristics of mandibular unicystic ameloblastoma. MATERIALS AND METHODS: The researchers compared and analysed the clinical and radiological features of 79 cases of mandibular unicystic ameloblastoma confirmed by histopathlogic examination. RESULTS: The results of our research showed that unicystic ameloblastomas occurred more frequently in males than in females and the incidence is the highest in the 2nd and 3rd decades. These lesions occurred most frequently in angle-ramus area, mandibular molar area, and anterior area in descending order respectively 68.4%, 24%, and 7.6%. These lesions had smooth (54.4%) rather than undulating (45.6%) borders. These lesions showed welldefined borders in 59.5% among all the cases. Root resorption and loss of lamina dura were observed as 55.7% and 58.5% respectively. Displacement of mandibular canal was observed in 55.9% among all the related cases. Internal pattern of lesional radiolucency was observed as even (49.4%) or uneven (50.6%). CONCLUSION: These results would be helpful in diagnosing of mandibular unicystic ameloblastoma.
Ameloblastoma* ; Female ; Humans ; Incidence ; Male ; Molar ; Radiography ; Root Resorption

PURPOSE: The purpose of this study was to investigate whether the fractal dimension and radiographic image brightness of periapical radiograph were useful in predicting osteoporosis. MATERIALS AND METHODS: Ninety-two postmenopausal women were classified as normal, osteopenia and osteoporosis group according to the bone mineral density of lumbar vertebrae and periapical radiographs of both mandibular molar areas were taken. The ROIs of 358 areas were selected at periapical and interdental areas and fractal dimension and radiographic image brightness were measured. RESULTS: The fractal dimension in normal group was significantly higher than that in osteoporosis group at periapical ROI (P< 0.05). The radiographic image brightness in normal group was higher than that in osteopenia and osteoporosis group. There was significant difference not only between normal and osteopenia group (P< 0.05) but also within osteopenia and osteoporosis group (P< 0.01) at periapical ROI. Significant difference was observed not only between normal and osteopenia group but also between normal and osteoporosis group at interdental ROI (P< 0.01). Positive linear relationship was weakly shown at Pearson correlation analysis between fractal dimension and radiographic image brightness. BMD significantly correlated with fractal dimension at periapical ROI (P< 0.01), and BMD and radiographic image brightness significantly correlated at both periapical and interdental ROIs (P< 0.01). CONCLUSION: This study suggests that the fractal dimension and radiographic image brightness of periapical ROI may predict BMD.
Bone Density ; Bone Diseases, Metabolic ; Female ; Fractals* ; Humans ; Lumbar Vertebrae ; Molar ; Osteoporosis* ; Radiography

PURPOSE: (1) To analyse the effect of exposure time, ROI size and one impact factor in the image processing procedure on estimates of fractal dimension; and (2) to analyse the correlated relationship between the fractal dimension and the Cu-Eq value (bone density). MATERIALS AND METHODS: The cylindric bone phantoms of 6 large and 5 small diameter having different bone densities respectively and human dry mandible segment with copper step wedge were radiographed at 1.0 and 1.2 sec esposure (70 kVp, 7 mA) using one occlusal film and digitized. Eleven rectangular ROIs from 11 cylindric bone phantoms and 4 rectangular ROIs from cortical, middle, periodontal regions, and socket of bone were selected. Gaussian blurred Image was subtracted from original image of each ROI and multiplied respectively by 1, 0.8, and 0.5, and then the image was made binary, eroded and dilated once, and skeletonized. The fractal dimension was calculated by means of a box counting method in the software ImageJ. RESULTS: The fractal dimension was decreased gradually with continued bone density decrease showing strong correlations (bone phantom; r> 0.87, bone; r> 0.68) under 70 kVp 1.0 sec M = 0.8. Fractal dimensions showed the significant differerence (p< 0.05) between two different exposure times on the same small ROI of bone phantom. Fractal dimensions between two different sizes of ROI on bone phantom showed the significant differerence (p< 0.05) under 1.2 sec exposure, but did not show it (p> 0.05) under 1.0 sec exposure. CONCLUSIONS: Exposure time, ROI size, and modifying factor during subtracting could become impacting on the results of fractal dimension. Fractal analysis with thoroughly evaluated method considering the various impacting factors on the results could be useful in assessing the bone density in dental radiography.
Bone Density ; Copper ; Cytochrome P-450 CYP1A1 ; Fractals* ; Humans ; Mandible ; Radiography ; Radiography, Dental ; Skeleton

PURPOSE: To evaluate the stability of the segmental occlusal plane and anatomical line as the reference line for measuring the mesiodistal tooth angulation in panoramic radiography and to determine the mean angle and the range of the mesiodistal tooth angulation in Korean population with normal occlusions. MATERIALS AND METHODS: Twenty nine subjects (15 men, 14 women) with normal occlusion were selected. A total of 29 panoramic radiograms were taken at normal head position and then 10 images of 5 subjects selected were repeatedly taken with repositioning 2 times at each of the head down (V-shaped occlusion) and up (horizontal occlusion) for evaluation of stability of adopted reference lines by using PM2002CC (Planmeca, Finland). The images were traced with adoption of two test reference lines and the long axes of the teeth. The mesial angles formed by each reference line and the long axes of the teeth were measured and analyzed. RESULTS: With anatomical reference line, the mesiodistal tooth angulations of the molars showed the significant difference by over 5 degree between the normal and each changed head position. With segmented occlusal reference line, deviations of mesiodistal tooth angulations by the two changed head positions were less than 1 degree. The means, standard deviations, and maximum and minimum values of mesiodistal tooth angulations to segmental occlusal reference line on panoramic radiography were determined. CONCLUSION: It would appear that mesiodistal tooth angulations to segmental occlusal plane as reference line in panograms are predictable as standards of normal occlusion and useful for evaluation of tooth arrangement between adjacent teeth.
Dental Occlusion* ; Head ; Humans ; Male ; Molar ; Radiography ; Radiography, Panoramic* ; Tooth*

PURPOSE: To compare cephalometric measurement between measuring methods in digital and conventional lateral cephalometric radiograph. MATERIALS AND METHODS: Twenty digital and conventional lateral cephalometric radiographs were selected. In digital group, cephalometric measurements were performed manually using hardcopies and automatically using VCeph(TM) program on the monitor. In conventional group, the same measurements were performed manually on conventional films, and for automatic measurement conventional films were digitized by scanner. All measurements were performed twice by 4 observers, and 24 cephalometric variables were calculated and the time spent for each measurement was recorded. The differences in measurements data and the time spent for each measurement were compared within each group. Intra-observer and inter-observer comparisons were performed. RESULTS: In both groups, no statistically significant difference between manual and automatic measurements was observed and most of the variables didn't show statistically significant differences between methods. The observer with less experience tended to show statistically significant differences of measurements between methods, and differences from other observers. The differences of measurements between methods in digital group were lesser than those of conventional group with statistical significance in 8 variables out of 24. With automatic method and in digital group, the spent time was shorter. CONCLUSION: With direct digital radiograph, automatic method using manually idenitified landmarks can be preferable in cephalometric analysis.
Cephalometry ; Radiographic Image Enhancement

PURPOSE: To observe the histopathological changes in the pulp tissues of mandibular molars in streptozotocininduced diabetic rats after irradiation. MATERIALS AND METHODS: The male Sprague-Dawley rats weighing approximately 250 gm were divided into four groups: control, diabetes, irradiation, and diabetes-irradiation groups. Diabetes mellitus was induced in the rats by injecting streptozotocin. Rats in control and irradiation groups were injected with citrate buffer only. After 5 days, the head and neck region of the rats in irradiation and diabetes-irradiation groups were irradiated with a single absorbed dose of 10 Gy. All the rats were sacrificed at 3, 7, 14, 21, and 28 days after irradiation. The specimen including the mandibular molars were sectioned and observed using a histopathological method. RESULTS: In the diabetes group, capillary dilatation was observed. However, there was no obvious morphologic alteration of the odontoblasts. In the irradiation group, generalized necrosis of the dental pulp tissues was observed. Vacuolation of the odontoblasts and dilatation of the capillaries were noted in the early experimental phases. In the diabetes-irradiation group, generalized degeneration of the dental pulp tissues was observed. Vacuolation of the dental pulp cells and the odontoblasts was noted in the late experimental phases. CONCLUSION: This experiment suggests that dilatation of the capillaries in the dental pulp tissues is induced by diabetic state, and generalized degeneration of the dental pulp tissues is induced by irradiation of the diabetic group.
Animals ; Capillaries ; Citric Acid ; Dental Pulp* ; Diabetes Mellitus ; Dilatation ; Head ; Humans ; Male ; Molar ; Neck ; Necrosis ; Odontoblasts ; Rats* ; Rats, Sprague-Dawley ; Streptozocin ; Tooth

PURPOSE: To investigate the effects of irradiation on the calcium content and calcific nodule formation in the MC3T3-E1 osteoblastic cell line. MATERIALS AND METHODS: Cells were irradiated with a single dose of 2, 4 and 8 Gy at a dose rate of 5.38 Gy/min using a Cs-137 irradiator. After irradiation, the calcium content and calcific nodule formation were examined on the 1st, 2nd, 3rd and 4th week. RESULTS: A decreasing dose-dependent tendency of the cell proliferation rate was found in all irradiated groups of this experiment when compared with the unirradiated control group. In accordance with the duration of culture, there was no significant difference in the cell proliferation rate after irradiation of 2 Gy when compared with the unirradiated group, however a decreasing tendency was found in 4 Gy- and 8 Gy-irradiated groups. While an increase in total calcium content after irradiation of 2 Gy was found at week 1, week 2, and week 4, there was a decrease in calcium content at week 1 through 4 in the 8 Gy- irradiated group. Calcific nodule formation was increased in irradiated experimental groups when compared with the unirradiated control group in the 2 Gyirradiated group, but decreased in the 4Gy- and 8Gy-irradiated groups at the same stage. CONCLUSION: The results showed a mild increasing tendency of the calcific nodule formation after irradiation of 2 Gy. However, a decreased calcific nodule formation in 4Gy- and 8Gy-irradiated groups was found. Taken together, the irradiation of 2 Gy mildly activated bone formation, however 4 Gy or 8 Gy suppressed bone formation by decreasing cell numbers in the MC3T3-E1 osteoblastic cell line.
Calcium ; Cell Count ; Cell Line* ; Cell Proliferation ; Osteoblasts* ; Osteogenesis

Odontogenic keratocyst (OKC) with secondary inflammation involving the maxillary sinus was presented. Radiological diagnosis of this case was made based on the various findings from the cone-beam computed tomography, computed tomography and magnetic resonance images. There were calcified materials and impacted tooth within the lumen of the lesion, which is not uncommon in OKC. Histopathologic findings confirmed this lesion as OKC with secondary inflammation.
Calcinosis ; Cone-Beam Computed Tomography ; Diagnostic Imaging ; Inflammation ; Magnetic Resonance Spectroscopy ; Maxilla ; Maxillary Sinus ; Odontogenic Cysts ; Tooth, Impacted