• Imaging Science in Dentistry
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• 제44권3호
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• pp.185-191
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• 2014

Purpose: This study investigated the developmental stages of third molars in relation to chronological age and compared third molar development according to location and gender. Materials and Methods: A retrospective analysis of panoramic radiographs of 2490 patients aged between 6 and 24 years was conducted, and the developmental stages of the third molars were evaluated using the modified Demirjian's classification. The mean age, standard deviation, minimal and maximal age, and percentile distributions were recorded for each stage of development. A Mann-Whitney U test was performed to test the developmental differences in the third molars between the maxillary and mandibular arches and between genders. A linear regression analysis was used for assessing the correlation between the third molar development and chronological age. Results: The developmental stages of the third molars were more advanced in the maxillary arch than the mandibular arch. Males reached the developmental stages earlier than females. The average age of the initial mineralization of the third molars was 8.57 years, and the average age at apex closure was 21.96 years. The mean age of crown completion was 14.52 and 15.04 years for the maxillary and the mandibular third molars, respectively. Conclusion: The developmental stages of the third molars clearly showed a strong correlation with age. The third molars developed earlier in the upper arch than the lower arch; further, they developed earlier in males than in females.

• Imaging Science in Dentistry
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• 제30권1호
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• pp.11-15
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• 2000

Purpose: The primary objective of this study was to estimate the radiation absorbed doses in certain critical organs in the head and neck region with an Orthopos plus, a Panelipse, and a Panex-E machines. The second objective was to compare the absorbed doses between 5 inch by 12 inch and 6 inch by 12 inch image field for the Orthopos plus. Materials and Methods: Rando phantom and LiF TLD chips were used for dosimetry. The absorbed doses were measured at the thyroid gland, the submandibular gland, the parotid gland, the mouth floor, the maxillary sinus, the brain, the mandibular body, the mandibular ramus, the 2nd cervical spine and the skin over TMJ area. Results: The highest absorbed dose value was recorded at the mandibular ramus for the Orthopos plus with narrow image field. Higher absorbed dose values were recorded at the parotid gland, the mouth floor, the submandibular gland, and the 2nd cervical spine. The doses in the parotid gland were 597 μGy and 529 μGy with Orthopos plus, 638 μGy with Panelipse, and 1094μGy with Panex-E. Corresponding figures for the mandibular ramus were 2363 Gy and 1220 μGy, 248 μGy, and 118 μGy. The absorbed doses to the thyroid gland, the maxillary sinus, the brain, and the skin over TMJ were very low. Conclusion: Higher exposure values were recorded for the Orthopos plus than Panelipse and Panex-E. There was no significant differences of the absorbed doses according to the image field size.

• Imaging Science in Dentistry
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• 제43권3호
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• pp.201-207
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• 2013

A 40-year-old man suffered from a repeatedly recurrent desmoplastic ameloblastoma in the right maxillary anterior and premolar regions. During the first visit, the patient was provisionally histopathologically diagnosed with a developmental cyst, and it was confirmed to be unicystic ameloblastoma and resected. Four years later, the lesion recurred, and was diagnosed as a desmoplastic type of ameloblastoma and removed again. Then, 5 years after the second surgery, the lesion recurred again, and was diagnosed as a type containing a follicular pattern, recurrent ameloblastoma. A panoramic radiograph showed a multilocular and mixed radiolucent/radiopaque expansile lesion at the first visit, a unilocular cystic lesion confined to the premolar area at the second visit, and a small soap bubble appearance in the molar area in the final visit. Cone-beam computed tomographic images of the final recurrence of the tumor revealed multiple small cyst-like structures in the right maxillary anterior and posterior regions.

• Imaging Science in Dentistry
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• 제44권2호
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• pp.103-113
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• 2014

Purpose: In this study, we aimed to develop dental charts for Turkish children and young adults of both genders within the age group of 4.5-22.5 years according to tooth mineralization and eruption in a format similar to that proposed by AlQahtani et al. Materials and Methods: In total, 753 digital panoramic radiographs from 350 males and 403 females were assessed. The permanent teeth were evaluated according to the classification system described by Demirjian et al. The eruption stage was assessed with Bengston's system, which was modified by AlQahtani et al at four points. Results: Teeth generally developed earlier in females than in males. This was particularly notable in the age group of 5-14 years. However, this difference was usually visible in only one stage, not in all teeth. It has been determined that the mixed dentition period ended with the shedding of the second deciduous molars in both genders. Conclusion: The dental charts presented here included information that could be beneficial to dental clinicians in making appropriate diagnosis and planning orthodontic and surgical procedures. These charts also provided datasets for preliminary dental age estimation in Turkish children and young adults.

• Imaging Science in Dentistry
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• 제34권3호
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• pp.159-164
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• 2004

Purpose: To compare alveolar bony height of pantomograph with bony height of thin slice, multiplanar reformatted (MPR) Computed Tomograph. Materials and Methods : Panoramic radiograms of 12 young adult patients had been taken by one radologic technitian and the measurements were corrected by magnification ratio (1.20). The slice thickness of Multi-detector Computed Tomography (CT) was at least 1mm for the accuracy. The raw CT datas were imported into the V-works 4.0 (CyberMed Corp., Seoul, Korea) and transformed to MPR images. Pantomographic measurements of alveolar bone were compared to CT values by average mean bony height measurements for the accuracy. Inter-, and Intra-observer variability was evaluated. Results : There was no significant differences between height measurement of pantomography and that of CT (P>0.05). There were no significant differences in either inter-or intra-observer measurements (P>0.05). Conclusion : Pantomography showed relatively high accuracy and precision in measuring alveolar bony height.

• Imaging Science in Dentistry
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• 제40권4호
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• pp.197-201
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• 2010

Osteopetrosis is a rare bone disease characterized by systemic osteosclerosis due to an osteoclast dysfunction that decreases bone resorption. This report demonstrates two cases of adult osteopetrosis with secondary osteomyelitis of the maxilla, in siblings who are 43-year old female and 55-year old, male respectively. The common radiographic features of these cases were increased radiopacity in skull, rib and vertebra. The radiographic features that differed between these two cases were the osteosclerotic pattern of the jaw bones, that is, diffuse patterns in the female case, while the male case showed nodular patterns that were confined to the root apices. The diagnosis of osteopetrosis may be complicated due to the varying degree of osteosclerosis on panoramic radiograph. Additional radiographs such as the chest and skull radiograph may be helpful for the diagnosis of osteopetrosis.

• Imaging Science in Dentistry
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• 제48권4호
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• pp.277-281
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• 2018

Purpose: This study was performed to investigate the relationship between sleep bruxism(SB) and pulpal calcifications in young women. Materials and Methods: A total of 100 female participants between 20 and 31 years of age who were referred to our radiology clinic for a dental check-up, including 59 SB and 41 non-SB patients, were sampled for the analysis. SB was diagnosed based on the American Academy of Sleep Medicine criteria. All teeth were evaluated on digital panoramic radiographs to detect pulpal calcifications, except third molars, teeth with root canal treatment, and teeth with root resorption. Binary logistic regression analysis was used to determine the risk factors for pulpal calcifications. The Spearman correlation coefficient was applied and the Pearson chi-square test was used for categorical variables. To test intra-examiner reproducibility, Cohen kappa analysis was applied. P values <.05 were considered to indicate statistical significance. Results: A total of 2800 teeth were evaluated (1652 teeth from SB patients and 1148 from non-SB patients), and 61% of patients had at least 1 dental pulpal calcification. No statistically significant relationship was found between SB and pulpal calcifications (P>0.05). In SB patients, the total number of pulpal calcifications was 129, while in non-SB patients, it was 84. Binary logistic analysis showed that SB was not a risk factor for the presence of pulpal calcifications(odds ratio, 1.19; 95% CI, 0.52-2.69, P>.05). Conclusion: No relationship was found between SB and pulpal calcifications.

• Imaging Science in Dentistry
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• 제51권4호
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• pp.455-460
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• 2021

This report presents a rare case of maxillary osteoblastoma in a 17-year-old female. The patient presented with dull pain and facial asymmetry inferior to the left zygoma. An intraoral examination found a painless swelling on the buccal gingival tissue in the left posterior maxilla. Panoramic radiographs and multidetector computed tomographic images revealed an ill-defined, non-corticated, mixed attenuating entity of osseous density located within the left posterior maxilla apical to the left maxillary molars. The entity exhibited a heterogeneous internal structure with a fine granular appearance, and the periphery showed a partial hypo-attenuating rim along the antero-medial aspect. Expansion of the left posterior maxilla accompanied with displacement of the left maxillary sinus floor was noted. External root resorption of the first and second molars was noted, as well as postero-superior displacement of the third molar. The histopathologic diagnosis of the biopsy was osteoblastoma. Complete excision of the tumor was performed.

• Imaging Science in Dentistry
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• 제36권1호
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• pp.55-62
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• 2006

Purpose : To find the cause of root curvature by use of panoramic and lateral cephalometric radiograph. Materials and Methods : Twenty six 1st graders whose mandibular 1st molars .just emerged into the mouth were selected. Panoramic and lateral cephalometric radiograph were taken at grade 1 and 6, longitudinally. In cephalometric radio graph, mandibular plane angle, ramus-occlusal plane angle, gonial angle, and gonion-gnathion distance (Go-Gn distance) were measured. In panoramic radio graph, elongated root length and root angle were measured by means of digital subtraction radiography. Occlusal plane-tooth axis angle was measured, too. Pearson correlations were used to evaluate the relationships between root curvature and elongated length and longitudinal variations of all variables. Multiple regression equation using related variables was computed. Results : The Pearson correlation coefficient between curved angle and longitudinal variations of occlusal plane-tooth axis angle and ramus-occlusal plane angle was 0.350 and 0.401, respectively (p<0.05). There was no significant correlation between elongated root length and longitudinal variations of all variables. The resulting regression equation was $Y=10.209+0.208X_1+0.745X_2$ (Y: root angle, $X_1$: variation of occlusal plane-tooth axis angle, $X_2$: variation of ramus-occlusal plane angle). Conclusion : It was suspected that the reasons of root curvature were change of tooth axis caused by contact with 2nd deciduous tooth and amount of mesial and superior movement related to change of occlusal plane.

• Imaging Science in Dentistry
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• 제44권3호
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• pp.213-220
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• 2014

Purpose: This study was performed to determine the efficacy of observers' prediction for the need of bone grafting and presence of perioperative complications on the basis of cone-beam computed tomography (CBCT) and panoramic radiographic (PAN) planning as compared to the surgical outcome. Materials and Methods: One hundred and eight partially edentulous patients with a need for implant rehabilitation were referred for preoperative imaging. Imaging consisted of PAN and CBCT images. Four observers carried out implant planning using PAN image datasets, and at least one month later, using CBCT image datasets. Based on their own planning, the observers assessed the need for bone graft augmentation as well as complication prediction. The implant length and diameter, the need for bone graft augmentation, and the occurrence of anatomical complications during planning and implant placement were statistically compared. Results: In the 108 patients, 365 implants were installed. Receiver operating characteristic analyses of both PAN and CBCT preoperative planning showed that CBCT performed better than PAN-based planning with respect to the need for bone graft augmentation and perioperative complications. The sensitivity and the specificity of CBCT for implant complications were 96.5% and 90.5%, respectively, and for bone graft augmentation, they were 95.2% and 96.3%, respectively. Significant differences were found between PAN-based planning and the surgery of posterior implant lengths. Conclusion: Our findings indicated that CBCT-based preoperative implant planning enabled treatment planning with a higher degree of prediction and agreement as compared to the surgical standard. In PAN-based surgery, the prediction of implant length was poor.