• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.3
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• pp.296-301
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• 2008

Actinomyces is a part of the normal oral flora, but under certain circumstances it may become pathogenic. Actinomycosis is a chronic granulomatous infective disease caused by microaerophilic Gram-positive bacteria of the genus actinomyces. It can involve almost any system, but principally affects the head and neck. Because the lesions in the submandibular region and the angle of the jaw give the face a swollen, indurated appearance, actinomycosis of mandible can be easily misdiagnosed in its acute or early state of infection. In these cases the disease usually presented as a swelling suggestive of an abscess or mimicking a neoplasm. The yield from standard cultures was poor and repeated sampling and anaerobic culture may be needed to obtain a positive culture. So actinomycosis should always be considered in a differential diagnosis of all infections of the cervicofacial area. Diagnosis of actinomycosis is made based on the histopathology, the clinical presentation and past dental history. We experienced a case of actinomycosis in the masseter muscle and present the case with review of literature.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.16 no.1
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• pp.113-126
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• 1986

This study was undertaken to document and better define this condition to help clarify this clinical and radiographic appearances by the analysis of clinical and radiographic features of cementoma. A study was made of a series of 104 cases with cementoma. This investigation of cementoma revealed the following features: 1. The female occurred in 73% of periapical cemental dysplasia and benign cementoblastoma, and 80% of cementifying fibroma. 2. 40% of periapical cemental dysplasia occurred in the fifth decades, and 73% of benign cementoblastoma during the second and third decades, while there was no age predilection in the cementifying fibroma. 3. 63% of periapical cemental dysplasia occurred in the mandibular anterior region. 91% of benign cementoblastoma and 80% of cementifying fibroma occurred in the mandibular premolar and/or molar region. 4. There were no cases complaining the associated clinical signs and subjective symptoms in the periapical cemental dysplasia, however the patient complained the pain in 36% of benign cementoblastoma and 40% of cementifying fibroma. 5. There were no cases expanding the cortical plates in the periapical cemental dysplasia, however 73% of benign cementoblastoma and all of 5 cases of cementifying fibroma showed the expansion of cortical plates. 6. Several radiographic features of the periapical cemental dysplasia were shown: a. 29% of the cases had multiple lesions. b. 53% of the cases were in the mature stage. c. During the osteolytic stage, the alveolar lamina dura was lost in 89% of the cases.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.27 no.2
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• pp.83-90
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• 1997

This study was performed to demonstrate the effect of linear or nonlinear contrast enhancement on subtraction images. Three different textures were radiograped on dental film. The first radiograph was taken without the presence of an object. the second, which showed trabucular bone, was taken of the molar area of a human. the third radiograph was taken of the coronal part of molars. Each film was digitized into a 1312 x 1024 pixel x 8 bit depth matrix by means of a Nikon 35 mm film scanner(LS-3510AF, Japan) with fixed gain and internal dark current correction to maintain constant illumination. The scanner was interfaced to a Macintosh Le ill computer(Apple Computer, Charlotte, N.C) This resulted in three pairs of images, including different textures-plain, bone and enamel. Digital regular, linearly and nonlinearly enhanced subtraction was performed. Computer software was ,used to simulate lesions in the shape of a 2D-Gaussian curve on each of a pair of images. The each subtraction images were presented in a random sequence to two groups of 10 observers(students and dentists). ROC analysis was used to compare observer performance. The following results were obtained ; 1. All of LCE subtraction, equalized subtraction and regular subtraction images of plain texture were diagnosed the best by far. 2. The data revealed a siginificant LCE effect in both the student group and the expert group. 3. Clinical expertise was a helphul factor for the observers in this study.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.10 no.2
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• pp.106-113
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• 2014

Hyperventilation is produced by several distinct causes: anxiety, respiratory alkalosis, increased blood catecholamine levels, and a decrease in the level of the ionized calcium in the blood. The dental fears about acute pain, bleeding, needle, drill and dental surgery lead to the severe anxiety and increased blood catecholamine level. Therefore, the most dental patient should be cared gently as the stress reduction protocol. In spite of the gentle care, a hyperventilation were occurred during the surgical extraction of impacted third molar with pericoronitis. We suggest that the dental patients with anxiety disorder must be attention for the manifestation of hyperventilation, especially in the psychologic disabled patient.

• The korean journal of orthodontics
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• v.24 no.3 s.46
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• pp.509-519
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• 1994

Upper canine is described as 'cornerstone' of maxilla, and its importance is implicated by long root and good alveolar support. The incidence of impaction of upper canine is the second most frequent next to the third molar because it takes a long period of time to develop, and has a complicated path of eruption, and erupts lately. Generally, the patient who has a palatally impacted canine visit the clinic primarily due to a missing of canine after 12-13 years old. Palatally impacted canine is different from labially impacted canine in its cause and treatment process. It is due to malposition or anomalous lateral incisor rather than arch length deficiency. Once the impaction is identified, the first stage of the treatment is to localiz the lesion by radiographic examinations or others and according to severity, orthodontic traction, or transplantation should be considered, and comprehensive diagnosis and treatment plan of malocclusion should be estsblished. Properly managed impacted canine can provide funtion and esthetic through proper diagnosis and treatment of extraction of canine is not indicated.

• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1119-1125
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• 2003

Coherent multidimensional vibrational spectroscopy is a new technique for establishing correlations between features in vibrational spectra that are caused by intra- and intermolecular interactions. These interactions cause cross-peaks between vibrational transitions that reflect the coupling. In this paper, we use Doubly Vibrationally Enhanced Infrared Spectroscopy (DOVE-IR) and DOVE-Raman processes to obtain coherent two dimensional vibrational spectra. The spectra are fitted to obtain the dephasing rates and third order susceptibilities $(χ^{(3)})$ for the nonlinear processes. We show that the DOVE $χ^{(3)}$ values are directly related to the molar absorptivities and Raman $χ^{(3)}$. We then use these relationships to obtain estimates for the $χ^{(3)}$ of the stimulated photon echo and $χ^{(5)}$ of the six wave mixing spectroscopies, respectively. We also predict the ratio of the cascaded four wave mixing signal to the six wave mixing signal.

• The Journal of Korean Obstetrics and Gynecology
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• v.20 no.4
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• pp.160-174
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• 2007

Purpose: The purpose of this study was to investigate about missed abortion pathophysiology, diagnosis, medical treatment and to research the trend of the study related to missed abortion. Methods: We referred a PubMed site by using search word of "missed abortion"(Limits: 3 Year, only items with abstracts, Human). Results: 37 journals with 49 papers were searched. Conclusion: 1. The study of missed abortion pathophysiology was the following. The first was that important pathologies such as molar pregnancy and placental trophoblastic disease can be diagnosed by routine histopathologic analysis of product of conception following first-trimester spontaneous miscarriages. The second was that coelomic fluid leptin concentration in missed abortion is higher than in normal. The third was that adenosine deaminae activity in serum and placenta of patients with anembryonic pregnancies and missed abortions was low. The forth was that Leptotrichia amnionii sp. nov. was the etiopathogenetic factor in missed abortion. 2. Transvaginal ultrasound assessment of irregular vaginal bleeding is effective in diagonosis of missed abortion. 3. There were medical therapy with misoprostol, mifepristone or anti progesterone for missed abortion. Misoprostol was administrated oral(sublingual) and vaginal.

• Journal of Oral Medicine and Pain
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• v.25 no.1
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• pp.129-144
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• 2000

The purpose of this study was to examine dentin surface changes of extracted sound third molar specimens which were etched with 10% maleic acid and irradiated at $7-140J/cm^2$ with $CO_2$ and at $156-280J/cm^2$ with Nd:YAG laser. The results were as follows. 1. Dentin surfaces etched with 10% maleic acid and then irradiated at below of $42J/cm^2$ with $CO_2$ laser showed the retentive morphology for resin restoration. 2. Dentin surfaces irradiated at below of $42J/cm^2$ with $CO_2$ laser showed the increased acid-resistance. 3. Dentin surfaces irradiated at $218-280J/cm^2$ with Nd:YAG laser showed the retentive morphology. 4. Dentin surfaces irradiated at $218-280J/cm^2$ with Nd:YAG laser and etched 10% maleic acid and then $218-280J/cm^2$ with Nd:YAG laser showed the increased acid-resistance.

• Journal of Korean society of Dental Hygiene
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• v.19 no.6
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• pp.1089-1097
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• 2019

Objectives: The purpose of this study is to assess the accuracy of provisional restorative resins fabricated using dental three-dimensional (3D) printers. Methods: Provisional restorative resins were fabricated using the first molar of the right mandibular. Three groups comprising a total of 24 samples of such resins were fabricated. The prepared abutment was scanned initially and then designed using a computer-aided design (CAD) software. The conventional subtractive manufacturing system was employed to fabricate the first group of resins, while the second and third groups were fabricated using a digital light processing (DLP) 3D printer and a stereolithography (SLA) 3D printer, respectively. The internal surfaces of the resins were scanned and 3D measurements of the resins were taken to confirm their accuracy. Results: The root-mean-square deviation (RMS±SD) of the accuracy of the resins fabricated using the conventional subtractive manufacturing system, DLP 3D printer, and SLA 3D printer were 68.83±2.22 ㎛, 74.63±6.23 ㎛, and 61.74±4.09 ㎛, respectively. A one-way analysis of variance (ANOVA) test showed significant differences between the three groups (p < 0.05). Conclusions: Provisional restorative resins fabricated using DLP and SLA 3D printers demonstrated clinically-acceptable results.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.1
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• pp.32-35
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• 2011

Purpose: Mandibular angle fractures constitute approximately 30% of mandibular fractures, and the mandibular third molar is usually in line with the fracture. This study evaluated the relationship between the extraction of a tooth in line with a mandibular angle fracture and the infection rate. Methods: One hundred and forty seven patients with mandibular angle fractures containing a tooth in line with the fracture from 2005 to 2008 were enrolled in this study. The patients were divided into two groups based on an extraction, and the infection rates were evaluated in both groups. Results: An extraction was performed in 70 patients (47.6%) and postoperative infections occurred in 14 patients (9.5%). Six (8.6%) of the 70 patients in the extraction group and 8 (10.4%) of the 77 patients in the non-extraction group had an infection. There was no significant difference between the two groups (P=0.708). Conclusion: These results show that there is no increased risk of postoperative complications when a tooth is present