• Imaging Science in Dentistry
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• v.38 no.2
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• pp.117-120
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• 2008

The odontogenic keratocyst (OKC) is a developmental odontogenic cyst typically occurring in the jaws. Since the first description of OKC was published in 1956, the lesion has been of particular interest because of its specific histopathologic features, high recurrence rate, and aggressive behavior. Recurrences most commonly arise within bone at the site of the original cyst. However, as lining cells may find their way into surrounding tissues either from implantation during surgery or from cortical perforation recurrences may arise at a distance from the original cyst. Here, we report a rare case of recurrent OKC which was first developed in mandible and recurred within the masticatory space.

• Imaging Science in Dentistry
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• v.39 no.4
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• pp.195-198
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• 2009

Purpose : To establish reference doses of periapical radiography in Chonnam Province, Korea. Materials and Methods : The target-skin distances were measured for dental patient's 1235 exposures including 345 mandibular molar areas. Each periapical radiation exposure was simulated with exactly the same patients exposure parameters and the simulated radiation doses were measured utilizing Mult-O-Meter (Unfors Instruments, Billadal, Sweden). The measurements were done in 44 dental clinics with 49 dental x-ray sets in Chonnam Province for one or two weeks at each dental clinic during year 2006. Results : The third quartile patient surface doses were 2.8 mGy for overall periapical exposures and 3.2 mGy for periapical mandibular molar exposures. Conclusion : The third quartile patient surface doses in Chonnam Province can be used as a guide to accepted clinical practice to reduce patient radiation exposure for the surveyed reference doses were below the recommended dental periapical radiography dose of 7 mGy by IAEA.

• Imaging Science in Dentistry
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• v.51 no.1
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• pp.1-7
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• 2021

Purpose: The aim of this study was to assess artifacts generated in cone-beam computed tomography (CBCT) of 3 types of dental implants using 3 metal artifact reduction (MAR) algorithm conditions (pre-acquisition MAR, post-acquisition MAR, and no MAR), and 2 peak kilovoltage (kVp) settings. Materials and Methods: Titanium-zirconium, titanium, and zirconium alloy implants were placed in a dry mandible. CBCT images were acquired using 84 and 90 kVp and at normal resolution for all 3 MAR conditions. The images were analyzed using ImageJ software (National Institutes of Health, Bethesda, MD) to calculate the intensity of artifacts for each combination of material and settings. A 3-factor analysis of variance model with up to 3-way interactions was used to determine whether there was a statistically significant difference in the mean intensity of artifacts associated with each factor. Results: The analysis of all 3 MAR conditions showed that using no MAR resulted in substantially more severe artifacts than either of the 2 MAR algorithms for the 3 implant materials; however, there were no significant differences between pre- and post-acquisition MAR. The 90 kVp setting generated less intense artifacts on average than the 84 kVp setting. The titanium-zirconium alloy generated significantly less intense artifacts than zirconium. Titanium generated artifacts at an intermediate level relative to the other 2 implant materials, but was not statistically significantly different from either. Conclusion: This in vitro study suggests that artifacts can be minimized by using a titanium-zirconium alloy at the 90 kVp setting, with either MAR setting.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.25 no.2
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• pp.569-578
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• 1995

Condylar hyperplasia is a self-limiting condition characterized by a slowly progressing, enlargement of the mandible that results in facial asymmetry and a crossbite malocclusion. The facial asymmetry, open bite or crossbite, and radiographic evidence of an enlarged condyle confirm the diagnosis of condylar hyperplasia. The etiology of the condition is unknown. This condition usually first becomes apparent during the second decade of life, when one condyle continues to grow while the other is no longer active. Radiographically, the condyle may appear enlarged or the neck of the condyle maybe elongated or both may occur, Sometimes, however, no radiographically demonstrable condylar abnormality will be noted. Surgical correction with subcondylar osteotomy is the treatment of choice. We have observed two cases of condylar hyperplasia occurred in the left mandibular condyle of 24-year-old and 35-year-old women. We obtained that two cases were shown the followed results; 1. Clinically, both cases was unilaterally developed on C/C area, with temporomandibular disorders and pain, facial asymetry and malocclusion. 2. Radiographically, hyperplastic mass confined to the condyle. 3. Histopathologically, these cases shown increased hypertrophic region in parts, and lamellated bone with irregular trabeculae.

• Imaging Science in Dentistry
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• v.33 no.4
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• pp.239-244
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• 2003

Malignant fibrous histiocytoma (MFH) is a pleomorphic soft tissue sarcoma. Three cases of MFH were reported in our study. The first case involved in the right infratemporal fossa of a 32-year-old female was presented. MR imaging revealed a 5.0 × 3.3 cm soft tissue mass of inhomogeneous high signal intensity. The second case was found in the right hard palate of a 66-year-old male. CT demonstrated bone destruction and MR imaging showed a 4 × 4 cm sized soft tissue mass of heterogeneous high signal intensity. The final case was found in the left masticator space of a 37-year-old male. The CT image showed a large mass with massive bone destruction of the left mandibular ramus, while the MRI displayed a soft tissue mass, 8 cm diameter. Our cases exhibited the general features of MFH. MRI is essential in the imaging of MFH, namely to depict tumor borders and demonstrate relationships with adjacent structures.

• Imaging Science in Dentistry
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• v.38 no.2
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• pp.121-124
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• 2008

The unicystic ameloblastoma (UA) is a variant of the solid or multicystic ameloblastoma, a less encountered variant of the ameloblastoma. It appears more frequently in the second or third decade with no sexual or racial predilection. It is almost exclusively encountered asymptomatic ally in the posterior mandible. We report a case of a 43-year old patient with UA, who had previously undergone a surgical treatment on the same site about 1year ago, this lesion recurred and presented as an exophytic gingival lesion in the anterior mandibular region.

• Imaging Science in Dentistry
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• v.40 no.4
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• pp.187-189
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• 2010

Aspergilloma of the paranasal sinus is a non-invasive form of aspergillosis, most often in the maxillary sinus. This case presents an 86-year-old female with aspergilloma of the left maxillary sinus. The patient's chief complaint was intermittent pain on the left maxillary first premolar area. A radiopacification of the left maxillary sinus was observed on the panoramic radiograph. Cone-beam computed tomography revealed complete radiopacification of the left maxillary sinus and scattered multiple radiopaque mass inside the lesion. Biopsy was performed under local anesthesia. On microscopic examination, numerous fungal hyphae, which branch at acute angle, were observed. The diagnosis was made as an aspergilloma based on the histopatholgic examination.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.25 no.1
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• pp.141-150
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• 1995

종양유발성 골연화증은 종양에 의하여 생성된 활동성 펩티드호르몬과 유사한 물질이 골이나 위장관에 작용하여 칼슘대사와 인대사의 변화를 일으키거나, 정상적인 비타민 D대사에 장애를 일으킴으로써 2차적으로 발생되는 대사성 질환으로 알려져 있다. 이의 발생빈도는 매우 낮으며, 임상적으로는 체중과 신장의 감소, 전신적인 골격의 동통 및 근무력증과 병적 골절이 동반되어 나타난다. 방사선사진에서는 골소주의 전반적인 소실, 피질골의 비박, 위골절, 치조백선의 소실 등을 보이고, 실험실 소견에서는 혈청인의 농도와 신세뇨관에서 인의 재흡수율의 감소 및 혈청 알칼리성 인산화효소 농도의 상승이 관찰된다. 본질환은 종양이 제거되면 별도의 부가적인 치료 없이도 임상적, 방사선학적 소견 및 실험실 소견의 뚜렷한 개선을 보이므로 이의 치료에 있어서 정확한 진단이 매우 중요하다. 저자들은 전신적인 동통과 근무력증을 주소로 내원한 환자들에게서 발생된 종양유발성 골연화증 3예를 경험하였기에 문헌고찰과 함께 이를 보고하는 바이다.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.24 no.2
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• pp.461-466
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• 1994

신경초종은 신경초에서 발생되는 성장이 느린 양성 종양으로 단발성이며 드물다. 이 종양은 말초 신경,자율 신경,뇌신경의 Schwann세포에서 발생된다. 두경부 영역의 두개외 신경성 종양은 드물며 특히 타액선에서 발생되는 예는 드물다. 저자들은 20세 여자 환자에서 아래와 같은 소견을 나타내는 신경초종을 경험하였기에 보고하는 바이다. 1.주소는 좌측 악하선 부위의 종창이었으며 촉진시 3×4㎝의 단단한 종괴가 만져졌으나 동통이나 림프절병증은 없었다. 2. 일반방사선사진에서 종괴와 관련된 골변화는 없었으나 초음파 영상에서는 불균질한 반사 양상을 보이는 종괴가 좌측 악하선 영역에서 관찰되었다. 3. 자기공명영상으로 병소의 정확한 위치를 확인할 수 있었다. 병소의 경계는 명확하였으나 신호 강도는 균일하지 않았으며 T1 강조 영상에서는 근육과 유사한 신호 강도를 보였으나 T2 강조 영상에서는 근육보다 높은 신호 강도를 나타냈다. 4. 조직 병리학적으로 Antoni type B 부위보다는 A 부위가 지배적이었으며 Verocay body도 나타났다. 종양 세포는 anti-S-100 염색에 양성으로 반응하였다.

• Imaging Science in Dentistry
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• v.32 no.2
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• pp.113-118
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• 2002

Ankylosis of joint is defined as limited movement due to infection, trauma, or surgical procedure. A 59-year-old female with a chief complaint of limited movements during mouth opening had a positive history of trauma to her right TMJ area about 5 years ago. From that time, progressive mouth opening limitation and intermittent pain have occurred. At the time of admission the patient showed mandibular deviation to the right side during mouth opening, with a maximum opening limited to 5 mm. On plain radiographs, right condylar enlargement and joint space reduction by newly formed bony tissues were observed. CT scans showed right condylar enlargement, cortical sclerosis, and thickening of the condyle, articular fossa and articular eminence.