• Imaging Science in Dentistry
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• 제42권3호
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• pp.129-137
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• 2012

Purpose: To compare different radiographic methods for assessing endodontically treated teeth. Materials and Methods: Root canal treatments were applied in 120 extracted mandibular teeth, which were divided into four groups: (1) ideal root canal treatment (60 teeth), (2) insufficient lateral condensation (20 teeth), (3) root canals filled short of the apex (20 teeth), (4) overfilled root canal treatment (20 teeth). The teeth were imaged using intraoral film, panoramic film, digital intraoral systems (CCD and PSP), CCD obtained with portable X-ray source, digital panoramic, and CBCT images obtained at 0.3 $mm^3$ and 0.2 $mm^3$ voxel size. Images were evaluated separately by three observers, twice. Kappa coefficients were calculated. The percentage of correct readings obtained from each modality was calculated and compared using a t-test (p<0.05). Results: The intra-observer kappa for each observer ranged between 0.327 and 0.849. The inter-observer kappa for each observer for both readings ranged between 0.312 and 0.749. For the ideal root canal treatment group, CBCT with 0.2 $mm^3$ voxel images revealed the best results. For insufficient lateral condensation, the best readings were found with periapical film followed by CCD and PSP. The assessment of teeth with root canals filled short of the apex showed the highest percentage of correct readings by CBCT and CCD. For the overfilled canal treatment group, PSP images and conventional periapical film radiographs had the best scores. Conclusion: CBCT was found to be successful in the assessment of teeth with ideal root canal treatment and teeth with canals filled short of the apex.

• Imaging Science in Dentistry
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• 제48권2호
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• pp.87-96
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• 2018

Purpose: The present study aimed to evaluate which of the following imaging methods best assessed misfit at the tooth-restoration interface: (1) bitewing radiographs, both conventional and digital, performed using a photostimulable phosphor plate (PSP) and a charge-coupled device (CCD) system; (2) panoramic radiographs, both conventional and digital; and (3) cone-beam computed tomography (CBCT). Materials and Methods: Forty healthy human molars with class I cavities were selected and divided into 4 groups according to the restoration that was applied: composite resin, composite resin with liner material to simulate misfit, dental amalgam, and dental amalgam with liner material to simulate misfit. Radiography and tomography were performed using the various imaging methods, and the resulting images were analyzed by 2 calibrated radiologists. The true presence or absence of misfit corresponding to an area of radiolucency in regions subjacent to the esthetic and metal restorations was validated with microscopy. The data were analyzed using a receiver operating characteristic (ROC) curve, and the scores were compared using the Cohen kappa coefficient. Results: For bitewing images, the digital systems (CCD and PSP) showed a higher area under the ROC curve (AUROC) for the evaluation of resin restorations, while the conventional images exhibited a larger AUROC for the evaluation of amalgam restorations. Conventional and digital panoramic radiographs did not yield good results for the evaluation of resin and amalgam restorations (P<.05). CBCT images exhibited good results for resin restorations(P>.05), but showed no discriminatory ability for amalgam restorations(P<.05). Conclusion: Bitewing radiographs (conventional or digital) should be the method of choice when assessing dental restoration misfit.

• 치과방사선
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• 제21권1호
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• pp.119-125
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• 1991

In the study of magnification of image in the focal trough of panoramic radiography, (Yoshida company Panoura - Eight - s), a series of 63 x-ray films were taken with the 8-19 metal pins placed in the holes of the plastic plate, measured and evaluated by 4 observes. The author analyzed the vertical and horizontal magnification rate in the corrected focal trough. Results were as follows: 1. For vertial measurements, magnification rates were minimum 10% maximum 36% and the magnification for image of medial side was larger than that of image of lateral side from image layer. 2. For horizontal measurements, magnification rates were minimum-14% maximum 46% and images of medial side from focal trough were magnified and images of lateral side from focal trough were retrenched. 3. When moved 10㎜ downward occlusal layer, interspace was somewhat narrow between the pins and upper sides of pins were horizontally magnified but images of the end parts of pins showed tapered form. 4. When moved 10㎜ downward from the occlusal layer, opposite images showed overlapping.

• Imaging Science in Dentistry
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• 제52권1호
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• pp.117-121
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• 2022

This report presents the case of a 49-year-old man who presented with giant masses that had recently grown on the bilateral sides of the tongue. A clinical examination revealed rubbery yellowish lesions protruding from the tongue. A panoramic radiograph showed an enlarged soft tissue shadow of the tongue. Computed tomography showed well-defined circumscribed mass exhibiting a homogeneous low density on the bilateral sides of the tongue. On magnetic resonance images, the masses showed a high signal intensity on T1-weighted images and iso-signal intensity with partially hyperintense margin on fat-suppressed T2-weighted images. Surgical excision was performed, and a histopathologic examination confirmed the diagnosis of lipoma. The patient recovered well with no sign of recurrence. A giant lipoma is defined as a lipoma larger than 5 cm in diameter. A literature review of giant lipomas of the tongue is also presented herein.

• Imaging Science in Dentistry
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• 제54권2호
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• pp.207-210
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• 2024

Ameloblastic fibrodentinoma (AFD) is a rare benign odontogenic tumor that resembles an ameloblastic fibroma with dysplastic dentin. This report presents a rare case of mandibular AFD with imaging features in a young patient. Panoramic radiography and computed tomography revealed a well-defined lesion with internal septa and calcified foci, causing inferior displacement of the adjacent molars as well as buccolingual cortical thinning and expansion of the posterior mandible. The lesion was surgically removed via mass excision, and the involved tooth was extracted under general anesthesia. During the 5-year follow-up period, no evidence of recurrence was observed. Radiologic features of AFD typically reveal a moderately to well-defined mixed lesion with varying degrees of radiopacity, reflecting the extent of dentin formation. Radiologists should consider AFD in the differential diagnosis when encountering a multilocular lesion with little dense radiopacity, particularly if it is associated with delayed eruption, impaction, or absence of involved teeth, on radiographic images of young patients.

• Restorative Dentistry and Endodontics
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• 제44권4호
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• pp.39.1-39.8
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• 2019

The present report presents a case of dens invaginatus (DI) in a patient with 4 maxillary incisors. A 24-year-old female complained of swelling of the maxillary left anterior region and discoloration of the maxillary left anterior tooth. The maxillary left lateral incisor (tooth #22) showed pulp necrosis and a chronic apical abscess, and a periapical X-ray demonstrated DI on bilateral maxillary central and lateral incisors. All teeth responded to a vitality test, except tooth #22. The anatomic form of tooth #22 was similar to that of tooth #12, and both teeth had lingual pits. In addition, panoramic and periapical X-rays demonstrated root canal calcification, such as pulp stones, in the maxillary canines, first and second premolars, and the mandibular incisors, canines, and first premolars bilaterally. The patient underwent root canal treatment of tooth #22 and non-vital tooth bleaching. After a temporary filling material was removed, the invaginated mass was removed using ultrasonic tips under an operating microscope. The working length was established, and the root canal was enlarged up to #50 apical size and obturated with gutta-percha and AH 26 sealer using the continuous wave of condensation technique. Finally, non-vital bleaching was performed, and the access cavity was filled with composite resin.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권5호
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• pp.340-345
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• 2009

Purpose: The purpose of this study was to evaluate the surgical success of bone reconstruction of the severely atrophic maxilla using autogenous block bone onlay graft from the ramus and ilium prior to dental implantation. And we measured the amount of vertical height change Material and Methods: 26 partially edentulous patients(32 case) who needed block onlay bone graft before implant placement in posterior maxillary area from 2002 to 2009 were selected for this study. Patients consisted of 20 males & 6 females and the average of their age was 54.2. Patients who were treated with ramal bone were 19 case and patients who were treated with iliac bone were 11 case. Digital panoramic X-ray was taken at the day of surgery, 3 months and 6 months later after the surgery. Vertical height change & resorption rate of grafted bone were measured with the same X-rays and compared Results: Two out of 32 bone grafts had to be removed because of inflamation at the grafts area(97.3%). The mean of radiographic vertical height change(change rate) of post-op. 3 month was 0.54mm(8.5%)and 6 month was 0.99mm(15.9%). Compairing to intraoral donor site(ramus), iliac bone had more vertical height change(1.18mm) at 6 month after surgery. Conclusions: Within the limit of this study, autogenous block onlay grafts can be considered a promising treatment for severely atrophic maxilla.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제23권2호
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• pp.107-114
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• 2001

Objectives : To compare jaw bone density of young adults (control group) and post-menopausal women(experimental group) in periapical and panoramic film. Materials and Methods : The bone mineral density values of lumbar and femur were measured by dual-energy X-ray absorptiometry(DEXA) and T scores of lumbar were obtained. T scores were classified into 3 group (T<-2.5, $-2.5{\leqq}T<-1$, $-1{\leqq}T$). Radiographic densities of alveolar bones were measured from interdental bones of premolar, molar areas in the maxilla and mandible and expressed into copper step wedge thickness by Scion $Image^{(R)}$ program. We considered these values of step wedge thickness as bone density of alveolar bone. Panorama mandibular index(PMI) was calculated by the method that the height of the inferior cortex of the mandible was divided by the height from the lower border of the mandible to the superior edge of the mental foramen. Bone density of alveolar bone and PMI were analysed statistically. Results : There were significant differences in bone mineral density of lumbar and femoral neck between control and experimental groups. There were also significant differences in bone density of premolar and molar area of jaw between control and experimental groups by MANOVA test. When considered lumbar T variables, there was only difference in interdental bone density of maxillary molar area between control and experimental group, but there was interaction. Interdental bone density of experimental group was appeared higher in $-1{\leqq}T$ group and lower in T<-2.5 group than control group. There was significant difference in PMI between control and experimental groups, but there was also inter action, thus, PMI of experimental group was appeared higher in $-1{\leqq}T$ group and lower in T<-2.5 group than control group. Conclusion : There were significant differences of alveolar density and cortical bone thickness between young men and post-menopausal women in periapical and panoramic film. These differences were dependent on lumbar T.

• Imaging Science in Dentistry
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• 제46권2호
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• pp.103-108
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• 2016

Purpose: The current study investigates the feasibility of a platform for a nationwide dose monitoring system for dental radiography. The essential elements for an unerring system are also assessed. Materials and Methods: An intraoral radiographic machine with 14 X-ray generators and five sensors, 45 panoramic radiographic machines, and 23 cone-beam computed tomography (CBCT) models used in Korean dental clinics were surveyed to investigate the type of dose report. A main server for storing the dose data from each radiographic machine was prepared. The dose report transfer pathways from the radiographic machine to the main sever were constructed. An effective dose calculation method was created based on the machine specifications and the exposure parameters of three intraoral radiographic machines, five panoramic radiographic machines, and four CBCTs. A viewing system was developed for both dentists and patients to view the calculated effective dose. Each procedure and the main server were integrated into one system. Results: The dose data from each type of radiographic machine was successfully transferred to the main server and converted into an effective dose. The effective dose stored in the main server is automatically connected to a viewing program for dentist and patient access. Conclusion: A patient radiation dose monitoring system is feasible for dental clinics. Future research in cooperation with clinicians, industry, and radiologists is needed to ensure format convertibility for an efficient dose monitoring system to monitor unexpected radiation dose.

• Imaging Science in Dentistry
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• 제32권3호
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• pp.141-145
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• 2002

Purpose : The purpose of this study was to propose standard values for alveolar and basal bone in normal adult mandibles, and radiologically analyze the remodeling process of the edentulous mandible by examining molar areas and comparing them to the established normal values. Materials and Methods : Panoramic and CT scans of mandible were performed on 20 normal adults and 20 edentulous or partially edentulous adults. In both groups, arch half diameter and distance of alveolar bone were measured. Also the distance from the mandibular canal to the caudal edges, the buccal and lingual external borders of basal bone, were measured. A statistical comparison between the mean values of normal and edentulous mandibles was carried out in the selected areas. Results : There was evidence of decreasing arch half diameter and distance in the edentulous mandible, but statistically no significant change was seen between the normal and edentulous alveolar bone. There was evidence of decreasing buccal basal bone and increasing in the lingual basal bone in the edentulous mandible. A statistically significant difference between normal and edentulous mandibles was noted in the buccal basal bone. Conclusion: There was an inward and forward atrophic change of the edentulous mandibular molar area compared to the control. CT scanning required the use of sophisticated and expensive procedures to analyze the remodeling process of edentulous mandibles. Consequently, the development and application of a more simplified and objective radiographic procedure for broad and long-term study of remodeling procedures of edentulous mandible was recommended.