• 치과방사선
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• 제18권1호
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• pp.153-163
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• 1988

The purpose of this study is to investigate on the clinical and radiographic patterns of cystogenic ameloblastoma of the jaws. The author studied 64 cases of cystogenic ameloblastoma with regard to age, sex distribution, the site of the lesion and several radiographic features. The results were as follows: 1. The average age was found to be 23.0 years, with a range of 4 to 56 years. The incidence was highest in the second and third decades (72%) and total 64 cases consists of 36 males and 28 females. 2. Fifty-nine cases were found in mandible and 5 cases in maxilla. 3. The specific site distribution was found to be 57.8% ramus, coronoid process and condyle, 34.4% premolar-molar region, and 7.8% were located in mandibular symphysis bilaterally. 4. From the total 64 cases, 28 (44%) were associated with an impacted tooth, especially mandibular second and third molar, 36(52%) failed to show any association with tooth impaction. It was found that the average age for impaction-associated tumors was 19.8 years whereas lesions without impaction occurred at an average age of 25.6 years, which was statistically significant. 5. Fifty-three(82%) cases showed unilocular radiolucencies, eleven (17%) cases showed multilocular radiolucencies. It was found that the average age for unilocular lesions was 22.3 years whereas lesions showing multilocularity occurred at an average age of 26.4 years, which was not statistically significant. 6. Of the 21 patients who had been followed for more than 2 years, only 4 patients treated by enucleation or curettage recurred (19% recurrence).

• Journal of Periodontal and Implant Science
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• 제25권3호
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• pp.568-586
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• 1995

542 periodontal patients having early-onset periodontitis(EOP) have been reclassified into a more homogeneous phenotypic subsets by newly revised radiographic criteria. Representative patients of each EOP subform have been examined of serum IgG subclass antibodies against periodontopathic bacteria, Porphyromonas gingivalis(Pg) 381 and of genetic markers for IgG allotypes to clarify the relationship between these parameters and phenotype expression of each subform. The early onset periodontitis could be reclassified by the radiographic parameters combining the mean interproximal alveolar bone loss(BL) and the radiographic ratio(between 1st molars and the adjacent teeth: Ratio) with statistical significance(p<0.001 by MANOVA). Moreover these EOP subforms could clearly be delineated from adult periodontitis. Of subform I and II(localized type EOP) patients with minimal mean bone loss(BL<5.0), patients demonstrating disease activities in localized areas(Ratio.>1.5) showed the elevated responses in all the IgG subclasses against Pg compared with those of patients without disease activity(Ratio <1.5). There were gradual increase in the IgG2 and IgG4 titers against Pg as the disease developed into the generalized forms suggesting the possible role of these antibodies in modulating the phenotype expression. The genetic marker study for IgG allotype revealed that mean IgG2 and IgG4 subclass titers were significantly higher(p<0.01, p<0.05, respectively) in patients who were positive for G2m(n). This indicated that IgG subclass responsiveness against the bacterial antigens are under the immnuogenetic control. The observed frequencies of G2m(n) were significantly higher (p<0.05) in subfrom IV patients who had the characteristic features of classical rapidly progressing periodontitis indicating the possible genetic predisposition in these patients.

• 치과방사선
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• 제23권2호
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• pp.255-264
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• 1993

The purpose of this study was to obtain some informations for the radiographic differential diagnosis between dentigerous cysts and unicystic ameloblastomas in the mandible. The authors observed and compared the clinico-radiographic features of 38 cases of dentigerous cyst and 32 cases of unicystic ameloblastoma associated with impacted mandibular molar. The obtained results were as follows: Dentigerous cysts occurred the most frequently in the 3rd decade, but unicystic ameloblastomas in the 2nd decade, and both lesions occurred with slight predilection in males. Average of lesional size of unicystic ameloblastomas was larger than that of dentigerous cysts, and lesions of over 25㎠ were only in unicystic ameloblastomas. Cortical thinning and expansion were more frequently observed in unicystic ameloblastomas at 72.9% than in dentigerous cysts at 15.8%. Dentigerous cysts showed smooth border at 89.5%, but unicystic ameloblastomas showed smooth border at 53.1% and scalloped border at 46.9%. Dentigerous cysts showed well-defined outline at 81.6%, but unicystic ameloblastomas showed well-defined outline at 53.1% and moderate-defined outline at 46.9%. In both lesions, the mandibular 3rd molar was the most frequent causative tooth. Average of distance between the cemento-enamel junction and lesional wall attachment of the causative tooth was longer in unicystic ameloblastomas than in dentigerous cysts. Severe displacement of causative tooth was more frequent in unicystic ameloblastomas at 62.5% than in dentigerous cysts at 23.7%. Dentigerous cysts showed homogeneous lesional radiolucency at 89.5%, but unicystic ameloblastomas showed inhomogeneous lesional radiolucency at 53.1%. Root resorption of adjacent tooth and displacement of mandibular canal were more frequent in unicystic ameloblastomas at 65.2% and 61.5% than in dentigerous cysts at 15.8% and 38.1% respectively.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제21권1호
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• pp.41-47
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• 1999

The route of bony invasion and spread pattern of tumor in the mandible are important in management of gingival cancer. Ten patients with gingival cancer involving mandibular body region were operated by composite resection. The radiographic and histopathologic features of the mandibular invasion and spread were analysed and compared. Our results showed that histopathologic extent of tumor invasion were greater than the radiographic prediction, especially in width of the tumor. And the pattern of bony invasion in the body area was mostly found in transmedullary spread rather than perineural spread. The vertical involvement in the mandibular body with tumor was evaluated. It indicated that if a oncologic surgeon was to ensure an adequate safety margin for extirpation of tumor, in most cases, the maintenance of the mandibular continuity is difficult. If the mandibular involvement by gingival cancer was identified radiographically and clinically, segmental mandibulectomy was required for the adequate safety margin, in consideration of the spread pattern in the body area.

• Imaging Science in Dentistry
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• 제54권1호
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• pp.71-80
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• 2024

Purpose: This study aimed to evaluate age-stratified radiographic features in temporomandibular joint osteoarthritis using cone-beam computed tomography. Materials and Methods: In total, 210 joints from 183 patients(144 females, 39 males, ranging from 12 to 88 years old with a mean age of 44.75±19.97 years) diagnosed with temporomandibular joint osteoarthritis were stratified by age. Mandibular condyle position and bony changes (flattening, erosion, osteophytes, subchondral sclerosis, and subchondral pseudocysts in both the condyle and articular eminence, thickening of the glenoid fossa, joint space narrowing, and joint loose bodies) were evaluated through cone-beam computed tomography. After adjusting for sex, the association between age groups and radiographic findings was analyzed using both a multiple regression model and a multinomial logistic regression model(α=0.05). Results: The prevalence of joint space narrowing and protruded condyle position in the glenoid fossa significantly increased with age (P<0.05). The risks of bony changes, including osteophytes and subchondral pseudocysts in the condyle; flattening, erosion, osteophyte, and subchondral sclerosis in the articular eminence; joint loose bodies; and thickening of the glenoid fossa, also significantly rose with increasing age (P<0.05). The number of radiographic findings increased with age; in particular, the increase was more pronounced in the temporal bone than in the mandibular condyle (P<0.05). Conclusion: Increasing age was associated with a higher frequency and greater diversity of bony changes in the temporal bone, as well as a protruded condyle position in the glenoid fossa, resulting in noticeable joint space narrowing in temporomandibular joint osteoarthritis.

• 치과방사선
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• 제21권2호
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• pp.275-285
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• 1991

The clinical and radiographic features of 655 congenitally missing teeth were studied with full mouth periapical radiograms and/or pantomograms from 368 persons visited the Department of Oral Radiology, Infirmary of Dentistry, Kyung Hee University during January 1981 to December 1989. The obtained results were as follows: 1. The prevalence of congenitally missing teeth was revealed to be 8.75% in total examined persons, and there was a higher prevalence in females (9.5%) than in males (8.0%). 2. The most frequently missing teeth were mandibular second premolars (24.6%), followed by mandibular lateral incisors (21.7%), maxillary second premolars (16.2%), and maxillary lateral incisors (11.5%). 3. There was a higher prevalence in the mandible (60.3%) than in the maxilla (39.7%), and no significant differences between right (49.65%) and left (50.35%) side. 4. In number of congenitally missing teeth per person, 54.6% had one missing tooth, and 32.9% had two missing teeth. 5. In persons with one or two congenitally missing teeth, the most frequently missing tooth was mandibular lateral incisor, and the second premolar was the tooth most frequently missing in those persons with more than three congenitally missing teeth.

• Imaging Science in Dentistry
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• 제35권3호
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• pp.141-146
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• 2005

Purpose : The purpose of this study was to investigate the preliminary use of morphologic operation (MO) in analyzing trabecular pattern of alveolar bone for the predicting systemic osteoporosis. Materials and Methods : Study subjects consisted of 35 females (average age 48.5 years) and 25 males (average age 25.8 years). Bone mineral density BMD $(grams/cm^2)$ of lumbar spine and proximal femur of these subjects were measured by a dual energy X-ray absorptiometry (DEXA). Regions of interest (ROIs) were selected from the digitized periapical radiographs of subjects' posterior jaw. A custom computer program processed morphology operations of ROIs. We compared mean values of 11 MO variables according to the osteoporotic group divided by the T-scores of DEXA. We also studied correlation between radiographic density and these MO variables. Results : The mean radiographic densities insignificantly correlated with MO variables. There were statistically significant differences among the values of 9 MO variables according to the osteoporotic group. Conclusion Morphologic operation can be effective in analyzing trabecular pattern of alveolar bone for the predicting osteoporosis.

• 치과방사선
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• 제20권2호
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• pp.227-234
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• 1990

The purpose of this study was to evaluate the incidence and several radiographic features of dilacerated teeth in 2132 full month radiograms in Korean. The results were as follows: 1. The occurrence was revealed to 2.7% in total examined teeth, and these anomalies were occurred in maxilla (52.4%) more than in mandible (47.6%). 2. There was a predilection for occurrence of dilaceration in female, which included 12.8% of the female compared to 11.3% in male. 3. The frequency of dilaceration in male, which included 40.5% in maxilla and 59.5% in mandible. The frequency of dilaceration in female, which included 52.4% in maxilla and 47.6% in mandible. 4. The order of frequency of dilaceration was second premolar, first premolar, lateral incisor, canine in maxilla, and first premolar, second premolar, canine, lateral incisor, central incisor in mandible. 5. In classifying of dilacerated teeth into 3 types by following appearances such as root curvature. Distal dilaceration was by far most common containing 65.8% of the cases. The least frequent was mesial dilaceration, which included 6.5% of the cases.

• 치과방사선
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• 제21권1호
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• pp.109-118
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• 1991

The author studied the age distribution, etiology, affected site and several radiographic features of periapical granulomas, cysts, and abscesses. The material consisted of 928 films obtained from the patients who were diagnosed and treated under the diagnosis of periapical granulomas, cysts, and abscesses during the past 8 years (1979-1986) at the Infirmary of Dental School, Chosun University. The obtained results were as follows: 1. The order of incidence was as follows: periapical abscess (67.2%), granuloma, and cyst. 2. The age distribution revealed the highest incidence around the age of 30 and relatively higher incidence over the age of 60 in the case of periapical abscess and granuloma. 3. In the frequency of location: Periapical abscesses occured most frequently in the mandibular molars. Granulomas showed relatively higher incidence in maxilla than in mandible. Cysts were most common in the maxillary anterior teeth. 4. The mean diameter of dental granuloma was 5.9㎜, however, all dental granulomas were less than 9.3㎜ in diameter. The mean diameter of periapical cyst was l3.8㎜. 5. Periapical cyst revealed well circumscribed radiolucent lesions and 77.8% of the lesion showed white line. 86.0% of dental granuloma showed well circumscribed border, 54.5% sclerosis on surrounding bone and 38.5% partial white line. Periapical abscess revealed diffuse radiolucent lesion, 89.6% of the lesions had sclerosis on surrounding bone, and 38.0% sinus tract.

• 치과방사선
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• 제10권1호
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• pp.15-28
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• 1980

The author studied age and sex distribution, etiology, affected site and several radiographic features of osteomyelitis of the jaw. And radiologic classification of osteomyelitis was also done. The material consisted of 118 males and 96 females examined and/or treated under the diagnosis of osteomyelitis during past 11 years (1970-1980.6) in SNUDH. The obtained results were as followings. 1. The incidence is the highest in teenages(22.9%) and the lowest in seventies. (2.8%). 2. 199 cases were found in lower jaw, and 15 cases in upper jaw. 30.8% of all cases were located at the posterior portion of mandibular body comprising alveolar region. 3. Radiographic examination of osteolytic lesion revealed that 21. 5% of all patients had periapical and alveolar bone rarefaction combined with osteoporotic changes and that in most of patients two or more of the above described changes were present at the same time. 4. Sclerotic lesions were seen in 62.2 % of all patients and 21.5% of sclerotic lesion were diffuse or homogenuous type. 5. Based on the radiologic study, classification of the osteomyelitis of the jaw was made. Loclized osteolytic type was the highest in incidence (38.8%) and localized sclerotic type was the lowest (7.0%)