17-year-old and 14-year-old brothers were referred for evaluation of the cystic lesions on the mandibular anterior area with no symptoms. Neither their mother nor the brothers could recall any past trauma to those areas. Panoramic and intraoral radiographs revealed moderately defined cystic lesions on their mandibular anterior areas. Biopsies on both lesions revealed simple bone cysts. Hereditary cause or familial history of simple bone cysts could not be found in literature review. This case may have been a coincidence. However, further investigation is needed to find the cause of simple bone cysts occurring in patients those are closely related.
Adolescent ; Biopsy ; Bone Cysts ; Humans ; Mothers ; Siblings

A 27-year-old female was referred to our hospital postpartum due to rapid aggravation of facial swelling. She was diagnosed with osteomyelitis on clinical, radiological, and histopathological examinations, but the possibility of malignancy was not excluded. Clinical signs and symptoms such as facial swelling and discomfort were improved with four months of antibiotics treatment. This is a case of an osteomyelitis progressed from infected extraction socket in a woman with physiological changes of pregnancy. Decreased immunological response, increased sex hormone and calcium regulatory hormones regulate the response of the bone infection. We report this case for helping the diagnosis of unusual form of osteomyelitis in pregnancy and postpartum.
Adult ; Anti-Bacterial Agents ; Calcium ; Female ; Humans ; Molar, Third ; Osteomyelitis ; Postpartum Period ; Pregnancy

PURPOSE: To assess the diagnostic accuracy and value in an imaging technique field through the comparison of cone beam computed tomography and conventional panoramic radiography in assessing the topographic relationship between the mandibular canal and impacted third molars. MATERIALS AND METHODS: Participants consisted of 100 patients offered the images through cone beam computed tomography and panoramic radiography. PSR-9000(TM) Dental CT system (Asahi Roentgen Ind. Co., Ltd, Japan) was used as the unit of cone beam computed tomography. CE-II (Asahi Roentgen Ind. Co., Ltd, Japan) and Pro Max (Planmeca Oy, Finland) were used as the unit of panoramic radiography. The images obtained through panoramic radiography were classified into 3 types according to the distance between mandibular canal and root of mandibular third molar. And they were classified into 4 types according to the proximity of radiographic feature. The images obtained through cone beam computed tomography based on the classification above were classified into 4 types according to the location between the mandibular canal and the root and were analyzed. And they were classified into buccal, inferior, lingual, and between roots, according to the location between mandibular canal and root. The data were statistically analyzed and estimated by chi-square-test. RESULTS: 1. There was no statistical significance according to 3 types (type l, type ll, type lll) through CBCT. 2. The results of 4 types (type A, type B, type C, type D) through CBCT were as high prevalence of CBCT 1 in type A, CBCT 2 in type B, CBCT 3 in type C, and CBCT1 in type D and those of which showed statistical significance (P value=0.03). 3. The results according to location between mandibular canal and root through CBCT recorded each 49, 25, 17, 9 as buccal, inferior, lingual, between roots. CONCLUSION: When estimating the mandibular canal and the roots through the panoramic radiography, it could be difficult to drive the views of which this estimation was considerable. Thus it is required to have an accurate diagnostic approaching through CBCT that could estimate the location between mandibular canal and roots.
Cone-Beam Computed Tomography ; Humans ; Mandibular Nerve ; Molar, Third ; Prevalence ; Radiography, Panoramic

PURPOSE: The purpose of this study is to evaluate the position of the mandibular canal in relation to the mandibular third molar by cone beam CT in cases showing a close relationship between the third molar and the mandibular canal on the panoramic radiograph. MATERIALS AND METHODS: The panoramic images and cone beam CT scans of 87 impacted mandibular third molars in 60 patients were evaluated to assess the tooth relationship to the mandibular canal. The clearness of the canal wall and the vertical depth of the lower third molar were evaluated on panoramic radiographs. The lower third molars were assessed using cone beam CT to determine the proximity and position of the canal relative to the roots. RESULTS: In the 66 cases where the canal wall was unclear on the panoramic radiographs, 58 (87.9%) of the third molars had contact between the canal and root; 34 (51.5%) canals were showed an inferior position and 22 (33.3%) showed a linguoinferior position on cone beam CT. CONCLUSION: Interruption of the canal wall on panoramic radiographs was highly predictive of contact between the mandibular canal and the third molar. Cross sectional CT may be indicated for localization of the mandibular canal in such cases.
Cone-Beam Computed Tomography ; Humans ; Mandibular Nerve ; Molar, Third ; Radiography, Panoramic ; Tooth

PURPOSE: To compare and evaluate the diagnostic ability of cone beam computed tomography (CBCT) and magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ). MATERIALS AND METHODS: CBCT and MRI of 46 TMJs of 23 patients with TMJ disorders were evaluated. They were divided into 3 groups according to the position of the articular disc of the TMJ at closed mouth position and the reduction of the disc during open mouth position on MRI : no disc displacement group (NDD), disc displacement with reduction group (DDR), and disc displacement without reduction group (DDWR). With PACS viewing softwares, position of mandibular condyle in the articular fossa, osseous change of mandibular condyle, shape of articular fossa, and mediolateral and anteroposterior dimensions of mandibular condyle were evaluated on CBCT and MRI. Each value was tested statistically. RESULTS: The position of mandibular condyle in the articular fossa were concentric in the NDD, DDR, and DDWR of CBCT and NDD of MRI. However, condyle was positioned posteriorly in DDR and DDWR of MRI. Flattening, sclerosis and osteophyte of the mandibular condyle were much more apparent on DDR of CBCT than MRI. And the erosion of the condyle was much more apparent on DDWR of MRI than CBCT. Box and Sigmoid types of articular fossa were found most frequently in DDR of MRI. Flattened type was found most frequently in DDR of CBCT and deformed type was found most frequently in DDWR of CBCT. No significant difference in mediolateral and anteroposterior dimensions were shown on CBCT and MRI. CONCLUSION: Since MRI and CBCT has unique diagnostic imaging ability, both modalities should be used together to supplement each other to evaluate TMJ.
Colon, Sigmoid ; Cone-Beam Computed Tomography ; Diagnostic Imaging ; Displacement (Psychology) ; Humans ; Magnetic Resonance Imaging ; Magnetic Resonance Spectroscopy ; Magnetics ; Magnets ; Mandibular Condyle ; Mouth ; Osteophyte ; Sclerosis ; Temporomandibular Joint ; Temporomandibular Joint Disorders

PURPOSE: To estimate the shape of root and pulp canal using a dental cone beam computed tomography (CBCT) and to evaluate the accuracy of imaging reformation. MATERIALS AND METHODS: CBCT images were obtained with incisors, premolars, and molars as the destination by using PSR 9000NTM Dental CT system (Asahi Roentgen Ind. Co., Ltd, Kyoto, Japan) and i-CAT (Imaging Sciences International, Inc, USA) cone beam CT unit that have different kind of detector and field of view, and compared these with the shape and the size of actual root and root canal. RESULTS: When the measuring value of cone beam computed tomography concerning to each root's bucco-lingual diameter and mesio-distal diameter was compared with the value of the actual root, it reveals an error range -0.49 ~+0.63 mm at PSR900N and -0.97~+1.14 mm at i-CAT(P.0.05). It was possible to identify and measure PSR 9000NTM Dental CT system to the limit 0.48+/-0.06 mm (P.0.05) and i-CAT CBCT to the limit 0.86+/-0.09 mm (P.0.05) on estimating the size and the shape of root canal. Two kinds of CBCT images revealed the useful reproducibility to estimate the shape of root, but there was the difference to estimate the shape of root according to apparatus. The reproducibility of root shape in the image of three-dimensions at PSR 900N is low such as 0.65 mm in a case of minute root canal. CONCLUSIONS: CBCT images revealed higher accuracy of the imaging reformation for root and pulp and clinically CBCT is a useful diagnostic tool for the assessment of root and canal. However, there are different qualities of imaging reformation according to CBCT apparatus and limitation of reproducibility for minute root canals.
Bicuspid ; Cone-Beam Computed Tomography* ; Dental Pulp Cavity* ; Incisor ; Molar ; Radiography, Dental ; Tomography, X-Ray Computed ; Tooth*

PURPOSE: To evaluate the characteristics of (widely used) cone beam computed tomography (CBCT) images. MATERIALS AND METHODS: Images were obtained with CT performance phantoms (The American Association of Physicists in Medicine; AAPM). CT phantom as the destination by using PSR 9000N(TM) dental CT system (Asahi Roentgen Ind. Co., Ltd., Japan) and i-CAT CBCT (Imaging Science International Inc., USA) that have different kinds of detectors and field of view, and compared these images with the CT number for linear attenuation, contrast resolution, and spatial resolution. RESULTS: CT number of both PSR 9000N(TM) dental CT system and i-CAT CBCT did not conform to the base value of CT performance phantom. The contrast of i-CAT CBCT is higher than that of PSR 9000N(TM) dental CT system. Both contrasts were increased according to thickness of cross section. Spatial resolution and shapes of reappearance was possible up to 0.6 mm in PSR 9000N(TM) dental CT system and up to 1.0 mm in i-CAT CBCT. Low contrast resolution in region of low contrast sensitivity revealed low level at PSR 9000N(TM) dental CT system and i-CAT CBCT. CONCLUSION: CBCT images revealed higher spatial resolution, however, contrast resolution in region of low contrast sensitivity was the inferiority of image characteristics.
Cone-Beam Computed Tomography* ; Contrast Sensitivity ; Phantoms, Imaging ; Radiography, Dental ; Tomography, X-Ray Computed

PURPOSE: The purpose of this study was to measure the absorbed dose and to calculate the effective dose for periapical radiography done by portable intraoral x-ray machines. MATERIALS AND METHODS: 14 full mouth, upper posterior and lower posterior periapical radiographs were taken by wall-type 1 and portable type 3 intraoral x-ray machines. Thermoluminescent dosemeters were placed at 23 sites at the layers of the tissue-equivalent ART woman phantom for dosimetry. Average tissue absorbed dose and radiation weighted dose were calculated for each major anatomical site. Effective dose was calculated using 2005 ICRP tissue weighted factors. RESULTS: On 14 full mouth periapical radiographs, the effective dose for wall-type x-ray machine was 30 Sv; for portable x-ray machines were 30 Sv, 22 Sv, 36 Sv. On upper posterior radiograph, the effective dose for wall-type x-ray machine was 4 Sv; for portable x-ray machines doses were 4 Sv, 3 Sv, 5 Sv. On lower posterior radiograph, the effective dose for wall type x-ray machine was 5 Sv; for portable x-ray machines doses were 4 Sv, 4 Sv, 5 Sv. CONCLUSION: Effective doses for periapical radiographs performed by portable intraoral x-ray machines were similar to doses for periapical radiographs taken by wall type intraoral x-ray machines.
Diagnostic Imaging ; Female ; Humans ; Mouth ; Radiation Monitoring ; Radiography* ; Radiography, Dental ; Radiometry ; Thermoluminescent Dosimetry

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.
Cone-Beam Computed Tomography* ; Humans ; Jeollabuk-do ; Mandibular Condyle* ; Osteophyte ; Sclerosis ; Temporomandibular Joint ; Temporomandibular Joint Disorders

PURPOSE: The purpose of this study was to evaluate the morphologic features of posterior edentulous mandible for Korean patients using cross-sectional CT images. MATERIALS AND METHODS: Computed tomographic cross-sectional views taken in 2004 and 2005 at Seoul National University Dental Hospital were analyzed by an oral and maxillofacial radiologist. Four indices were measured to meet the purpose of this study: 1) the horizontal distance between the alveolar crest and mandibular canal (Type), 2) the angle of the mandibular long axis (Angle), 3) the bucco-lingual location of mandibular canal, and 4) the depth of the submandibular fossa. The averages and standard deviations of the measurements were compared according to the location (the first and second molar area) and sex of the patients. RESULTS: Statistically significant difference was found in Type, Angle, and submandibular fossa depth between the first and second molar area (p.0.05). However, there was no significant difference between men and women in any of the measured indices. Most of the mandibular canals were located in lingual side of posterior mandible. CONCLUSION: More care should be taken when an implant is installed on the mandibular second molar area.
Alveolar Process ; Axis, Cervical Vertebra ; Female ; Humans ; Male ; Mandible ; Mandibular Nerve ; Molar ; Seoul ; Submandibular Gland ; Tomography, X-Ray Computed