• Imaging Science in Dentistry
• /
• 제45권3호
• /
• pp.169-174
• /
• 2015

Purpose: This study was performed to evaluate the diagnostic efficacy of panoramic radiography and cone-beam computed tomography (CBCT) in detecting sinus pathology. Materials and Methods: This study was based on a retrospective evaluation of patients who had undergone both a panoramic radiograph and a CBCT exam. A total of 100 maxillary sinuses were evaluated. Four examiners with various levels of expertise evaluated the images using a five-point scoring system. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic efficacy of the two modalities. The image analysis was repeated twice, with at least two weeks between the evaluation sessions. Interobserver reliability was assessed using Cronbach's alpha, and intraobserver reliability was assessed using Cohen's kappa. Results: Maxillary sinus pathology was detected in 72% of the patients. High interobserver and intraobserver reliability were observed for both imaging modalities and among the four examiners. Statistical analyses using ROC curves demonstrated that the CBCT images had a larger area under the curve (0.940) than the panoramic radiographs (0.579). Conclusion: Three-dimensional evaluation of the sinus with CBCT was significantly more reliable in detecting pathology than panoramic imaging.

• Imaging Science in Dentistry
• /
• 제49권1호
• /
• pp.65-70
• /
• 2019

Purpose: To determine whether calcified carotid atherosclerotic plaques(CCAPs) and mineralized laryngeal cartilages (MLCs) were more frequently detected on digital or film-based panoramic radiographs. The clinical relevance of this question is that some radiopacities seen on digital radiographs may correspond to medium-density tissues that are not necessarily mineralized. Materials and Methods: Data were collected from panoramic radiographs and the respective reports issued by 2 private oral radiology centers. A total of 388 radiographs and reports were divided into film-based (group A) and digital (group D) radiographs. The frequencies of CCAPs and MLCs were analyzed using the Fisher exact test, and odds ratios were also calculated (${\alpha}=1%$). Results: The mean age of patients whose reports and radiographs showed CCAPs and/or MLCs ranged from 50.1 to 54.1 years. There was a predominance of females. A higher frequency of CCAPs and MLCs was observed in group D than in group A at both centers(P<0.01). CCAPs and MLCs were detected 4 times more frequently in group D than in group A at one of the centers. Conclusion: CCAPs and MLCs were more frequently detected on digital than on film-based panoramic radiographs. Further studies are needed to determine whether such radiopacities do indeed correspond to mineralized, rather than medium-density, tissues.

• 치과방사선
• /
• 제25권2호
• /
• pp.437-445
• /
• 1995

The purpose of this study was to evaluate the equivalent and effective dose, and estimate radiation risk to the critical organs of head and neck region from the use of adult and child mode in panoramic radiography. The results were as follows. 1. The salivary glands showed the highest equivalent and effective dose in adult and child mode. the equivalent and effective dose in adult mode were 837μSv and 20.93μSv, those in child mode were 462μSv and 11.54μSv, respectively. 2. Total effective doses to the critical head and neck organs were estimated 34.21μSv in adult mode, 20.14μSv in child mode. From these datas, the probabilities of stochastic effect from adult and child mode were 2.50x10/sup -6/ and 1.47x10/sup -6/. 3. The other remainder showed the greatest risk of fatal cancer. The risk estimate were 4.5 and 2.7 fatal malignancies in adult and child mode from million panoramic examinations. The bone marrow and thyroid gland showed about 0.1 fatal cancer in adult and child mode from these examinations.

• Imaging Science in Dentistry
• /
• 제38권3호
• /
• pp.147-151
• /
• 2008

Purpose : The purpose of this study was to investigate whether fractal analysis of periapical and panoramic radiographs was useful in predicting osteoporosis risk. Materials and Methods : 37 postmenoposal women between the age of 42 and 79 were classified as normal and osteoporosis group according to the bone mineral density of lumbar vertebrae and periapical and panoramic radio-graphs were taken. Fractal dimensions at periapical areas of mandibular first molars were calculated to differentiate the two groups. Results : The mean fractal dimensions of normal group on periapical and panoramic radiographs were $1.413{\pm}0.079$, $1.517{\pm}0.071$ each. The mean fractal dimensions of osteoporotic group on periapical and panoramic radiographs were $1.498{\pm}0.086$, $1.388{\pm}0.083$ each. The mean fractal dimension from peripaical radiographs of osteoporotic group was statistically significantly higher than that of normal group. The mean fractal dimension from panoramic radiographs of osteoporotic group was statistically significantly lower than that of normal group. Conclusion : Fractal analysis using periapical and panoramic radiographs was useful in predicting osteoporosis.

• Imaging Science in Dentistry
• /
• 제35권2호
• /
• pp.63-68
• /
• 2005

Recently implant has become an important field in dental clinic. Radiographic examination of pre- and post- operation is essential for successful treatment. Clinicians should have knowledge about the purpose of the radiographic examination, suitable imaging modality for the cases, anatomic landmarks of tooth and jaw bone, advantage and limitation of panoramic radiographic examination for implant, principle and interpretation of cross-sectional imaging, bone mineral density, post-operative radiographic examination. This paper will be helpful to get above informations for dentists who want to do dental implant successfully.

• 치과방사선
• /
• 제28권1호
• /
• pp.111-126
• /
• 1998

In this study, radiographic evaluation was made using panoramic radiography and cross-sectional tomography of SCANORA/sup (R)/ 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 using 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 actual maxilla specimen were 2.83 mm, 4.51mm, and 4.l5mm, 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 relationship 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 molars, type II (the 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/sup (R)/ 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.

• Imaging Science in Dentistry
• /
• 제43권2호
• /
• pp.71-75
• /
• 2013

Purpose: This study was performed to determine the position of the mental foramen relative to the apices of the teeth based on panoramic radiographs in a Moroccan population. We also analyzed gender differences and the symmetry of location within individuals. Materials and Methods: Seven hundred ninety-four panoramic radiographs were evaluated with regard to the location and symmetry of the mental foramina in male and female subjects. The results were analyzed using Pearson's ${\chi}^2$ and Fisher's exact test. Results: Of the 794 panoramic radiographs, 377 met the inclusion criteria for at least one side. The mental foramen was located just below the apex of the second premolar in 62.7% of the patients and between the first and second premolars in 30%. It was symmetrically located in 79%. No statistically significant differences were found between males and females in the position and symmetry of the mental foramen. Conclusion: The most common position for the mental foramen in this sample was in line with the second premolar.

• Imaging Science in Dentistry
• /
• 제33권4호
• /
• pp.211-215
• /
• 2003

Purpose: To assess the radiographic findings of odontogenic cysts showing displacement of the mandibular canal using computed tomographic (CT) and panoramic images. Materials and Methods : CT and panoramic images of 63 odontogenic cysts (27 dentigerous, 16 odontogenic keratocysts, and 20 radicular cysts) were analyzed to evaluate the following parameters: the dimension and shape of the cysts, and the effect of the cysts on the mandibular canal and cortical plates. Results: Of the 63 cysts examined in the study, 35 (55.6%) showed inferior displacement of the mandibular canal and 46 (73.0%) showed perforation of the canal. There were statistically significant differences between CT and panoramic images in depicting displacement and perforation of the mandibular canal. Cortical expansion was seen in 46 cases (73.0%) and cortical perforation in 23 cases (36.5%). The radicular cysts showed cortical expansion and perforation less frequently than the other cyst groups. Conclusion: Large cysts of mandible should be evaluated by multiplanar CT images inorder to detect the mandibular canal and cortical bone involvement.

• Journal of Periodontal and Implant Science
• /
• 제42권4호
• /
• pp.144-144
• /
• 2012

• 대한치과교정학회:학술대회논문집
• /
• 대한치과교정학회 2005년도 제38회 학술대회
• /
• pp.62-64
• /
• 2005